Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next

Daniel Borkmann says:

====================
pull-request: bpf-next 2018-04-27

The following pull-request contains BPF updates for your *net-next* tree.

The main changes are:

1) Add extensive BPF helper description into include/uapi/linux/bpf.h
   and a new script bpf_helpers_doc.py which allows for generating a
   man page out of it. Thus, every helper in BPF now comes with proper
   function signature, detailed description and return code explanation,
   from Quentin.

2) Migrate the BPF collect metadata tunnel tests from BPF samples over
   to the BPF selftests and further extend them with v6 vxlan, geneve
   and ipip tests, simplify the ipip tests, improve documentation and
   convert to bpf_ntoh*() / bpf_hton*() api, from William.

3) Currently, helpers that expect ARG_PTR_TO_MAP_{KEY,VALUE} can only
   access stack and packet memory. Extend this to allow such helpers
   to also use map values, which enabled use cases where value from
   a first lookup can be directly used as a key for a second lookup,
   from Paul.

4) Add a new helper bpf_skb_get_xfrm_state() for tc BPF programs in
   order to retrieve XFRM state information containing SPI, peer
   address and reqid values, from Eyal.

5) Various optimizations in nfp driver's BPF JIT in order to turn ADD
   and SUB instructions with negative immediate into the opposite
   operation with a positive immediate such that nfp can better fit
   small immediates into instructions. Savings in instruction count
   up to 4% have been observed, from Jakub.

6) Add the BPF prog's gpl_compatible flag to struct bpf_prog_info
   and add support for dumping this through bpftool, from Jiri.

7) Move the BPF sockmap samples over into BPF selftests instead since
   sockmap was rather a series of tests than sample anyway and this way
   this can be run from automated bots, from John.

8) Follow-up fix for bpf_adjust_tail() helper in order to make it work
   with generic XDP, from Nikita.

9) Some follow-up cleanups to BTF, namely, removing unused defines from
   BTF uapi header and renaming 'name' struct btf_* members into name_off
   to make it more clear they are offsets into string section, from Martin.

10) Remove test_sock_addr from TEST_GEN_PROGS in BPF selftests since
    not run directly but invoked from test_sock_addr.sh, from Yonghong.

11) Remove redundant ret assignment in sample BPF loader, from Wang.

12) Add couple of missing files to BPF selftest's gitignore, from Anders.

There are two trivial merge conflicts while pulling:

  1) Remove samples/sockmap/Makefile since all sockmap tests have been
     moved to selftests.
  2) Add both hunks from tools/testing/selftests/bpf/.gitignore to the
     file since git should ignore all of them.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>

31 files changed, 5360 insertions, 2071 deletions

diff --git a/drivers/net/ethernet/netronome/nfp/bpf/jit.c b/drivers/net/ethernet/netronome/nfp/bpf/jit.c
index 29b4e5f8c102..65f0791cae0c 100644
--- a/drivers/net/ethernet/netronome/nfp/bpf/jit.c
+++ b/drivers/net/ethernet/netronome/nfp/bpf/jit.c
@@ -1214,45 +1214,83 @@ wrp_test_reg(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta,
 	return 0;
 }
 
-static int
-wrp_cmp_imm(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta,
-	    enum br_mask br_mask, bool swap)
+static const struct jmp_code_map {
+	enum br_mask br_mask;
+	bool swap;
+} jmp_code_map[] = {
+	[BPF_JGT >> 4]	= { BR_BLO, true },
+	[BPF_JGE >> 4]	= { BR_BHS, false },
+	[BPF_JLT >> 4]	= { BR_BLO, false },
+	[BPF_JLE >> 4]	= { BR_BHS, true },
+	[BPF_JSGT >> 4]	= { BR_BLT, true },
+	[BPF_JSGE >> 4]	= { BR_BGE, false },
+	[BPF_JSLT >> 4]	= { BR_BLT, false },
+	[BPF_JSLE >> 4]	= { BR_BGE, true },
+};
+
+static const struct jmp_code_map *nfp_jmp_code_get(struct nfp_insn_meta *meta)
+{
+	unsigned int op;
+
+	op = BPF_OP(meta->insn.code) >> 4;
+	/* br_mask of 0 is BR_BEQ which we don't use in jump code table */
+	if (WARN_ONCE(op >= ARRAY_SIZE(jmp_code_map) ||
+		      !jmp_code_map[op].br_mask,
+		      "no code found for jump instruction"))
+		return NULL;
+
+	return &jmp_code_map[op];
+}
+
+static int cmp_imm(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
 {
 	const struct bpf_insn *insn = &meta->insn;
 	u64 imm = insn->imm; /* sign extend */
+	const struct jmp_code_map *code;
+	enum alu_op alu_op, carry_op;
 	u8 reg = insn->dst_reg * 2;
 	swreg tmp_reg;
 
+	code = nfp_jmp_code_get(meta);
+	if (!code)
+		return -EINVAL;
+
+	alu_op = meta->jump_neg_op ? ALU_OP_ADD : ALU_OP_SUB;
+	carry_op = meta->jump_neg_op ? ALU_OP_ADD_C : ALU_OP_SUB_C;
+
 	tmp_reg = ur_load_imm_any(nfp_prog, imm & ~0U, imm_b(nfp_prog));
-	if (!swap)
-		emit_alu(nfp_prog, reg_none(), reg_a(reg), ALU_OP_SUB, tmp_reg);
+	if (!code->swap)
+		emit_alu(nfp_prog, reg_none(), reg_a(reg), alu_op, tmp_reg);
 	else
-		emit_alu(nfp_prog, reg_none(), tmp_reg, ALU_OP_SUB, reg_a(reg));
+		emit_alu(nfp_prog, reg_none(), tmp_reg, alu_op, reg_a(reg));
 
 	tmp_reg = ur_load_imm_any(nfp_prog, imm >> 32, imm_b(nfp_prog));
-	if (!swap)
+	if (!code->swap)
 		emit_alu(nfp_prog, reg_none(),
-			 reg_a(reg + 1), ALU_OP_SUB_C, tmp_reg);
+			 reg_a(reg + 1), carry_op, tmp_reg);
 	else
 		emit_alu(nfp_prog, reg_none(),
-			 tmp_reg, ALU_OP_SUB_C, reg_a(reg + 1));
+			 tmp_reg, carry_op, reg_a(reg + 1));
 
-	emit_br(nfp_prog, br_mask, insn->off, 0);
+	emit_br(nfp_prog, code->br_mask, insn->off, 0);
 
 	return 0;
 }
 
-static int
-wrp_cmp_reg(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta,
-	    enum br_mask br_mask, bool swap)
+static int cmp_reg(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
 {
 	const struct bpf_insn *insn = &meta->insn;
+	const struct jmp_code_map *code;
 	u8 areg, breg;
 
+	code = nfp_jmp_code_get(meta);
+	if (!code)
+		return -EINVAL;
+
 	areg = insn->dst_reg * 2;
 	breg = insn->src_reg * 2;
 
-	if (swap) {
+	if (code->swap) {
 		areg ^= breg;
 		breg ^= areg;
 		areg ^= breg;
@@ -1261,7 +1299,7 @@ wrp_cmp_reg(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta,
 	emit_alu(nfp_prog, reg_none(), reg_a(areg), ALU_OP_SUB, reg_b(breg));
 	emit_alu(nfp_prog, reg_none(),
 		 reg_a(areg + 1), ALU_OP_SUB_C, reg_b(breg + 1));
-	emit_br(nfp_prog, br_mask, insn->off, 0);
+	emit_br(nfp_prog, code->br_mask, insn->off, 0);
 
 	return 0;
 }
@@ -1400,7 +1438,7 @@ map_call_stack_common(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
 	if (!load_lm_ptr)
 		return 0;
 
-	emit_csr_wr(nfp_prog, stack_reg(nfp_prog),  NFP_CSR_ACT_LM_ADDR0);
+	emit_csr_wr(nfp_prog, stack_reg(nfp_prog), NFP_CSR_ACT_LM_ADDR0);
 	wrp_nops(nfp_prog, 3);
 
 	return 0;
@@ -2283,46 +2321,6 @@ static int jeq_imm(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
 	return 0;
 }
 
-static int jgt_imm(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
-{
-	return wrp_cmp_imm(nfp_prog, meta, BR_BLO, true);
-}
-
-static int jge_imm(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
-{
-	return wrp_cmp_imm(nfp_prog, meta, BR_BHS, false);
-}
-
-static int jlt_imm(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
-{
-	return wrp_cmp_imm(nfp_prog, meta, BR_BLO, false);
-}
-
-static int jle_imm(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
-{
-	return wrp_cmp_imm(nfp_prog, meta, BR_BHS, true);
-}
-
-static int jsgt_imm(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
-{
-	return wrp_cmp_imm(nfp_prog, meta, BR_BLT, true);
-}
-
-static int jsge_imm(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
-{
-	return wrp_cmp_imm(nfp_prog, meta, BR_BGE, false);
-}
-
-static int jslt_imm(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
-{
-	return wrp_cmp_imm(nfp_prog, meta, BR_BLT, false);
-}
-
-static int jsle_imm(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
-{
-	return wrp_cmp_imm(nfp_prog, meta, BR_BGE, true);
-}
-
 static int jset_imm(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
 {
 	const struct bpf_insn *insn = &meta->insn;
@@ -2392,46 +2390,6 @@ static int jeq_reg(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
 	return 0;
 }
 
-static int jgt_reg(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
-{
-	return wrp_cmp_reg(nfp_prog, meta, BR_BLO, true);
-}
-
-static int jge_reg(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
-{
-	return wrp_cmp_reg(nfp_prog, meta, BR_BHS, false);
-}
-
-static int jlt_reg(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
-{
-	return wrp_cmp_reg(nfp_prog, meta, BR_BLO, false);
-}
-
-static int jle_reg(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
-{
-	return wrp_cmp_reg(nfp_prog, meta, BR_BHS, true);
-}
-
-static int jsgt_reg(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
-{
-	return wrp_cmp_reg(nfp_prog, meta, BR_BLT, true);
-}
-
-static int jsge_reg(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
-{
-	return wrp_cmp_reg(nfp_prog, meta, BR_BGE, false);
-}
-
-static int jslt_reg(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
-{
-	return wrp_cmp_reg(nfp_prog, meta, BR_BLT, false);
-}
-
-static int jsle_reg(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
-{
-	return wrp_cmp_reg(nfp_prog, meta, BR_BGE, true);
-}
-
 static int jset_reg(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
 {
 	return wrp_test_reg(nfp_prog, meta, ALU_OP_AND, BR_BNE);
@@ -2520,25 +2478,25 @@ static const instr_cb_t instr_cb[256] = {
 	[BPF_ST | BPF_MEM | BPF_DW] =	mem_st8,
 	[BPF_JMP | BPF_JA | BPF_K] =	jump,
 	[BPF_JMP | BPF_JEQ | BPF_K] =	jeq_imm,
-	[BPF_JMP | BPF_JGT | BPF_K] =	jgt_imm,
-	[BPF_JMP | BPF_JGE | BPF_K] =	jge_imm,
-	[BPF_JMP | BPF_JLT | BPF_K] =	jlt_imm,
-	[BPF_JMP | BPF_JLE | BPF_K] =	jle_imm,
-	[BPF_JMP | BPF_JSGT | BPF_K] =  jsgt_imm,
-	[BPF_JMP | BPF_JSGE | BPF_K] =  jsge_imm,
-	[BPF_JMP | BPF_JSLT | BPF_K] =  jslt_imm,
-	[BPF_JMP | BPF_JSLE | BPF_K] =  jsle_imm,
+	[BPF_JMP | BPF_JGT | BPF_K] =	cmp_imm,
+	[BPF_JMP | BPF_JGE | BPF_K] =	cmp_imm,
+	[BPF_JMP | BPF_JLT | BPF_K] =	cmp_imm,
+	[BPF_JMP | BPF_JLE | BPF_K] =	cmp_imm,
+	[BPF_JMP | BPF_JSGT | BPF_K] =  cmp_imm,
+	[BPF_JMP | BPF_JSGE | BPF_K] =  cmp_imm,
+	[BPF_JMP | BPF_JSLT | BPF_K] =  cmp_imm,
+	[BPF_JMP | BPF_JSLE | BPF_K] =  cmp_imm,
 	[BPF_JMP | BPF_JSET | BPF_K] =	jset_imm,
 	[BPF_JMP | BPF_JNE | BPF_K] =	jne_imm,
 	[BPF_JMP | BPF_JEQ | BPF_X] =	jeq_reg,
-	[BPF_JMP | BPF_JGT | BPF_X] =	jgt_reg,
-	[BPF_JMP | BPF_JGE | BPF_X] =	jge_reg,
-	[BPF_JMP | BPF_JLT | BPF_X] =	jlt_reg,
-	[BPF_JMP | BPF_JLE | BPF_X] =	jle_reg,
-	[BPF_JMP | BPF_JSGT | BPF_X] =  jsgt_reg,
-	[BPF_JMP | BPF_JSGE | BPF_X] =  jsge_reg,
-	[BPF_JMP | BPF_JSLT | BPF_X] =  jslt_reg,
-	[BPF_JMP | BPF_JSLE | BPF_X] =  jsle_reg,
+	[BPF_JMP | BPF_JGT | BPF_X] =	cmp_reg,
+	[BPF_JMP | BPF_JGE | BPF_X] =	cmp_reg,
+	[BPF_JMP | BPF_JLT | BPF_X] =	cmp_reg,
+	[BPF_JMP | BPF_JLE | BPF_X] =	cmp_reg,
+	[BPF_JMP | BPF_JSGT | BPF_X] =  cmp_reg,
+	[BPF_JMP | BPF_JSGE | BPF_X] =  cmp_reg,
+	[BPF_JMP | BPF_JSLT | BPF_X] =  cmp_reg,
+	[BPF_JMP | BPF_JSLE | BPF_X] =  cmp_reg,
 	[BPF_JMP | BPF_JSET | BPF_X] =	jset_reg,
 	[BPF_JMP | BPF_JNE | BPF_X] =	jne_reg,
 	[BPF_JMP | BPF_CALL] =		call,
@@ -2777,6 +2735,54 @@ static void nfp_bpf_opt_reg_init(struct nfp_prog *nfp_prog)
 	}
 }
 
+/* abs(insn.imm) will fit better into unrestricted reg immediate -
+ * convert add/sub of a negative number into a sub/add of a positive one.
+ */
+static void nfp_bpf_opt_neg_add_sub(struct nfp_prog *nfp_prog)
+{
+	struct nfp_insn_meta *meta;
+
+	list_for_each_entry(meta, &nfp_prog->insns, l) {
+		struct bpf_insn insn = meta->insn;
+
+		if (meta->skip)
+			continue;
+
+		if (BPF_CLASS(insn.code) != BPF_ALU &&
+		    BPF_CLASS(insn.code) != BPF_ALU64 &&
+		    BPF_CLASS(insn.code) != BPF_JMP)
+			continue;
+		if (BPF_SRC(insn.code) != BPF_K)
+			continue;
+		if (insn.imm >= 0)
+			continue;
+
+		if (BPF_CLASS(insn.code) == BPF_JMP) {
+			switch (BPF_OP(insn.code)) {
+			case BPF_JGE:
+			case BPF_JSGE:
+			case BPF_JLT:
+			case BPF_JSLT:
+				meta->jump_neg_op = true;
+				break;
+			default:
+				continue;
+			}
+		} else {
+			if (BPF_OP(insn.code) == BPF_ADD)
+				insn.code = BPF_CLASS(insn.code) | BPF_SUB;
+			else if (BPF_OP(insn.code) == BPF_SUB)
+				insn.code = BPF_CLASS(insn.code) | BPF_ADD;
+			else
+				continue;
+
+			meta->insn.code = insn.code | BPF_K;
+		}
+
+		meta->insn.imm = -insn.imm;
+	}
+}
+
 /* Remove masking after load since our load guarantees this is not needed */
 static void nfp_bpf_opt_ld_mask(struct nfp_prog *nfp_prog)
 {
@@ -3212,6 +3218,7 @@ static int nfp_bpf_optimize(struct nfp_prog *nfp_prog)
 {
 	nfp_bpf_opt_reg_init(nfp_prog);
 
+	nfp_bpf_opt_neg_add_sub(nfp_prog);
 	nfp_bpf_opt_ld_mask(nfp_prog);
 	nfp_bpf_opt_ld_shift(nfp_prog);
 	nfp_bpf_opt_ldst_gather(nfp_prog);
diff --git a/drivers/net/ethernet/netronome/nfp/bpf/main.h b/drivers/net/ethernet/netronome/nfp/bpf/main.h
index 4981c8944ca3..68b5d326483d 100644
--- a/drivers/net/ethernet/netronome/nfp/bpf/main.h
+++ b/drivers/net/ethernet/netronome/nfp/bpf/main.h
@@ -236,6 +236,7 @@ struct nfp_bpf_reg_state {
  * @xadd_over_16bit: 16bit immediate is not guaranteed
  * @xadd_maybe_16bit: 16bit immediate is possible
  * @jmp_dst: destination info for jump instructions
+ * @jump_neg_op: jump instruction has inverted immediate, use ADD instead of SUB
  * @func_id: function id for call instructions
  * @arg1: arg1 for call instructions
  * @arg2: arg2 for call instructions
@@ -264,7 +265,10 @@ struct nfp_insn_meta {
 			bool xadd_maybe_16bit;
 		};
 		/* jump */
-		struct nfp_insn_meta *jmp_dst;
+		struct {
+			struct nfp_insn_meta *jmp_dst;
+			bool jump_neg_op;
+		};
 		/* function calls */
 		struct {
 			u32 func_id;
diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
index 3b5991734118..f34794a76c4d 100644
--- a/drivers/net/virtio_net.c
+++ b/drivers/net/virtio_net.c
@@ -765,7 +765,7 @@ static struct sk_buff *receive_mergeable(struct net_device *dev,
 			/* recalculate len if xdp.data or xdp.data_end were
 			 * adjusted
 			 */
-			len = xdp.data_end - xdp.data;
+			len = xdp.data_end - xdp.data + vi->hdr_len;
 			/* We can only create skb based on xdp_page. */
 			if (unlikely(xdp_page != page)) {
 				rcu_read_unlock();
diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h
index c8383a289f7b..da77a9388947 100644
--- a/include/uapi/linux/bpf.h
+++ b/include/uapi/linux/bpf.h
@@ -377,403 +377,1396 @@ union bpf_attr {
 	};
 } __attribute__((aligned(8)));
 
-/* BPF helper function descriptions:
- *
- * void *bpf_map_lookup_elem(&map, &key)
- *     Return: Map value or NULL
- *
- * int bpf_map_update_elem(&map, &key, &value, flags)
- *     Return: 0 on success or negative error
- *
- * int bpf_map_delete_elem(&map, &key)
- *     Return: 0 on success or negative error
- *
- * int bpf_probe_read(void *dst, int size, void *src)
- *     Return: 0 on success or negative error
+/* The description below is an attempt at providing documentation to eBPF
+ * developers about the multiple available eBPF helper functions. It can be
+ * parsed and used to produce a manual page. The workflow is the following,
+ * and requires the rst2man utility:
+ *
+ *     $ ./scripts/bpf_helpers_doc.py \
+ *             --filename include/uapi/linux/bpf.h > /tmp/bpf-helpers.rst
+ *     $ rst2man /tmp/bpf-helpers.rst > /tmp/bpf-helpers.7
+ *     $ man /tmp/bpf-helpers.7
+ *
+ * Note that in order to produce this external documentation, some RST
+ * formatting is used in the descriptions to get "bold" and "italics" in
+ * manual pages. Also note that the few trailing white spaces are
+ * intentional, removing them would break paragraphs for rst2man.
+ *
+ * Start of BPF helper function descriptions:
+ *
+ * void *bpf_map_lookup_elem(struct bpf_map *map, const void *key)
+ * 	Description
+ * 		Perform a lookup in *map* for an entry associated to *key*.
+ * 	Return
+ * 		Map value associated to *key*, or **NULL** if no entry was
+ * 		found.
+ *
+ * int bpf_map_update_elem(struct bpf_map *map, const void *key, const void *value, u64 flags)
+ * 	Description
+ * 		Add or update the value of the entry associated to *key* in
+ * 		*map* with *value*. *flags* is one of:
+ *
+ * 		**BPF_NOEXIST**
+ * 			The entry for *key* must not exist in the map.
+ * 		**BPF_EXIST**
+ * 			The entry for *key* must already exist in the map.
+ * 		**BPF_ANY**
+ * 			No condition on the existence of the entry for *key*.
+ *
+ * 		Flag value **BPF_NOEXIST** cannot be used for maps of types
+ * 		**BPF_MAP_TYPE_ARRAY** or **BPF_MAP_TYPE_PERCPU_ARRAY**  (all
+ * 		elements always exist), the helper would return an error.
+ * 	Return
+ * 		0 on success, or a negative error in case of failure.
+ *
+ * int bpf_map_delete_elem(struct bpf_map *map, const void *key)
+ * 	Description
+ * 		Delete entry with *key* from *map*.
+ * 	Return
+ * 		0 on success, or a negative error in case of failure.
+ *
+ * int bpf_probe_read(void *dst, u32 size, const void *src)
+ * 	Description
+ * 		For tracing programs, safely attempt to read *size* bytes from
+ * 		address *src* and store the data in *dst*.
+ * 	Return
+ * 		0 on success, or a negative error in case of failure.
  *
  * u64 bpf_ktime_get_ns(void)
- *     Return: current ktime
- *
- * int bpf_trace_printk(const char *fmt, int fmt_size, ...)
- *     Return: length of buffer written or negative error
- *
- * u32 bpf_prandom_u32(void)
- *     Return: random value
- *
- * u32 bpf_raw_smp_processor_id(void)
- *     Return: SMP processor ID
- *
- * int bpf_skb_store_bytes(skb, offset, from, len, flags)
- *     store bytes into packet
- *     @skb: pointer to skb
- *     @offset: offset within packet from skb->mac_header
- *     @from: pointer where to copy bytes from
- *     @len: number of bytes to store into packet
- *     @flags: bit 0 - if true, recompute skb->csum
- *             other bits - reserved
- *     Return: 0 on success or negative error
- *
- * int bpf_l3_csum_replace(skb, offset, from, to, flags)
- *     recompute IP checksum
- *     @skb: pointer to skb
- *     @offset: offset within packet where IP checksum is located
- *     @from: old value of header field
- *     @to: new value of header field
- *     @flags: bits 0-3 - size of header field
- *             other bits - reserved
- *     Return: 0 on success or negative error
- *
- * int bpf_l4_csum_replace(skb, offset, from, to, flags)
- *     recompute TCP/UDP checksum
- *     @skb: pointer to skb
- *     @offset: offset within packet where TCP/UDP checksum is located
- *     @from: old value of header field
- *     @to: new value of header field
- *     @flags: bits 0-3 - size of header field
- *             bit 4 - is pseudo header
- *             other bits - reserved
- *     Return: 0 on success or negative error
- *
- * int bpf_tail_call(ctx, prog_array_map, index)
- *     jump into another BPF program
- *     @ctx: context pointer passed to next program
- *     @prog_array_map: pointer to map which type is BPF_MAP_TYPE_PROG_ARRAY
- *     @index: 32-bit index inside array that selects specific program to run
- *     Return: 0 on success or negative error
- *
- * int bpf_clone_redirect(skb, ifindex, flags)
- *     redirect to another netdev
- *     @skb: pointer to skb
- *     @ifindex: ifindex of the net device
- *     @flags: bit 0 - if set, redirect to ingress instead of egress
- *             other bits - reserved
- *     Return: 0 on success or negative error
+ * 	Description
+ * 		Return the time elapsed since system boot, in nanoseconds.
+ * 	Return
+ * 		Current *ktime*.
+ *
+ * int bpf_trace_printk(const char *fmt, u32 fmt_size, ...)
+ * 	Description
+ * 		This helper is a "printk()-like" facility for debugging. It
+ * 		prints a message defined by format *fmt* (of size *fmt_size*)
+ * 		to file *\/sys/kernel/debug/tracing/trace* from DebugFS, if
+ * 		available. It can take up to three additional **u64**
+ * 		arguments (as an eBPF helpers, the total number of arguments is
+ * 		limited to five).
+ *
+ * 		Each time the helper is called, it appends a line to the trace.
+ * 		The format of the trace is customizable, and the exact output
+ * 		one will get depends on the options set in
+ * 		*\/sys/kernel/debug/tracing/trace_options* (see also the
+ * 		*README* file under the same directory). However, it usually
+ * 		defaults to something like:
+ *
+ * 		::
+ *
+ * 			telnet-470   [001] .N.. 419421.045894: 0x00000001: <formatted msg>
+ *
+ * 		In the above:
+ *
+ * 			* ``telnet`` is the name of the current task.
+ * 			* ``470`` is the PID of the current task.
+ * 			* ``001`` is the CPU number on which the task is
+ * 			  running.
+ * 			* In ``.N..``, each character refers to a set of
+ * 			  options (whether irqs are enabled, scheduling
+ * 			  options, whether hard/softirqs are running, level of
+ * 			  preempt_disabled respectively). **N** means that
+ * 			  **TIF_NEED_RESCHED** and **PREEMPT_NEED_RESCHED**
+ * 			  are set.
+ * 			* ``419421.045894`` is a timestamp.
+ * 			* ``0x00000001`` is a fake value used by BPF for the
+ * 			  instruction pointer register.
+ * 			* ``<formatted msg>`` is the message formatted with
+ * 			  *fmt*.
+ *
+ * 		The conversion specifiers supported by *fmt* are similar, but
+ * 		more limited than for printk(). They are **%d**, **%i**,
+ * 		**%u**, **%x**, **%ld**, **%li**, **%lu**, **%lx**, **%lld**,
+ * 		**%lli**, **%llu**, **%llx**, **%p**, **%s**. No modifier (size
+ * 		of field, padding with zeroes, etc.) is available, and the
+ * 		helper will return **-EINVAL** (but print nothing) if it
+ * 		encounters an unknown specifier.
+ *
+ * 		Also, note that **bpf_trace_printk**\ () is slow, and should
+ * 		only be used for debugging purposes. For this reason, a notice
+ * 		bloc (spanning several lines) is printed to kernel logs and
+ * 		states that the helper should not be used "for production use"
+ * 		the first time this helper is used (or more precisely, when
+ * 		**trace_printk**\ () buffers are allocated). For passing values
+ * 		to user space, perf events should be preferred.
+ * 	Return
+ * 		The number of bytes written to the buffer, or a negative error
+ * 		in case of failure.
+ *
+ * u32 bpf_get_prandom_u32(void)
+ * 	Description
+ * 		Get a pseudo-random number.
+ *
+ * 		From a security point of view, this helper uses its own
+ * 		pseudo-random internal state, and cannot be used to infer the
+ * 		seed of other random functions in the kernel. However, it is
+ * 		essential to note that the generator used by the helper is not
+ * 		cryptographically secure.
+ * 	Return
+ * 		A random 32-bit unsigned value.
+ *
+ * u32 bpf_get_smp_processor_id(void)
+ * 	Description
+ * 		Get the SMP (symmetric multiprocessing) processor id. Note that
+ * 		all programs run with preemption disabled, which means that the
+ * 		SMP processor id is stable during all the execution of the
+ * 		program.
+ * 	Return
+ * 		The SMP id of the processor running the program.
+ *
+ * int bpf_skb_store_bytes(struct sk_buff *skb, u32 offset, const void *from, u32 len, u64 flags)
+ * 	Description
+ * 		Store *len* bytes from address *from* into the packet
+ * 		associated to *skb*, at *offset*. *flags* are a combination of
+ * 		**BPF_F_RECOMPUTE_CSUM** (automatically recompute the
+ * 		checksum for the packet after storing the bytes) and
+ * 		**BPF_F_INVALIDATE_HASH** (set *skb*\ **->hash**, *skb*\
+ * 		**->swhash** and *skb*\ **->l4hash** to 0).
+ *
+ * 		A call to this helper is susceptible to change the underlaying
+ * 		packet buffer. Therefore, at load time, all checks on pointers
+ * 		previously done by the verifier are invalidated and must be
+ * 		performed again, if the helper is used in combination with
+ * 		direct packet access.
+ * 	Return
+ * 		0 on success, or a negative error in case of failure.
+ *
+ * int bpf_l3_csum_replace(struct sk_buff *skb, u32 offset, u64 from, u64 to, u64 size)
+ * 	Description
+ * 		Recompute the layer 3 (e.g. IP) checksum for the packet
+ * 		associated to *skb*. Computation is incremental, so the helper
+ * 		must know the former value of the header field that was
+ * 		modified (*from*), the new value of this field (*to*), and the
+ * 		number of bytes (2 or 4) for this field, stored in *size*.
+ * 		Alternatively, it is possible to store the difference between
+ * 		the previous and the new values of the header field in *to*, by
+ * 		setting *from* and *size* to 0. For both methods, *offset*
+ * 		indicates the location of the IP checksum within the packet.
+ *
+ * 		This helper works in combination with **bpf_csum_diff**\ (),
+ * 		which does not update the checksum in-place, but offers more
+ * 		flexibility and can handle sizes larger than 2 or 4 for the
+ * 		checksum to update.
+ *
+ * 		A call to this helper is susceptible to change the underlaying
+ * 		packet buffer. Therefore, at load time, all checks on pointers
+ * 		previously done by the verifier are invalidated and must be
+ * 		performed again, if the helper is used in combination with
+ * 		direct packet access.
+ * 	Return
+ * 		0 on success, or a negative error in case of failure.
+ *
+ * int bpf_l4_csum_replace(struct sk_buff *skb, u32 offset, u64 from, u64 to, u64 flags)
+ * 	Description
+ * 		Recompute the layer 4 (e.g. TCP, UDP or ICMP) checksum for the
+ * 		packet associated to *skb*. Computation is incremental, so the
+ * 		helper must know the former value of the header field that was
+ * 		modified (*from*), the new value of this field (*to*), and the
+ * 		number of bytes (2 or 4) for this field, stored on the lowest
+ * 		four bits of *flags*. Alternatively, it is possible to store
+ * 		the difference between the previous and the new values of the
+ * 		header field in *to*, by setting *from* and the four lowest
+ * 		bits of *flags* to 0. For both methods, *offset* indicates the
+ * 		location of the IP checksum within the packet. In addition to
+ * 		the size of the field, *flags* can be added (bitwise OR) actual
+ * 		flags. With **BPF_F_MARK_MANGLED_0**, a null checksum is left
+ * 		untouched (unless **BPF_F_MARK_ENFORCE** is added as well), and
+ * 		for updates resulting in a null checksum the value is set to
+ * 		**CSUM_MANGLED_0** instead. Flag **BPF_F_PSEUDO_HDR** indicates
+ * 		the checksum is to be computed against a pseudo-header.
+ *
+ * 		This helper works in combination with **bpf_csum_diff**\ (),
+ * 		which does not update the checksum in-place, but offers more
+ * 		flexibility and can handle sizes larger than 2 or 4 for the
+ * 		checksum to update.
+ *
+ * 		A call to this helper is susceptible to change the underlaying
+ * 		packet buffer. Therefore, at load time, all checks on pointers
+ * 		previously done by the verifier are invalidated and must be
+ * 		performed again, if the helper is used in combination with
+ * 		direct packet access.
+ * 	Return
+ * 		0 on success, or a negative error in case of failure.
+ *
+ * int bpf_tail_call(void *ctx, struct bpf_map *prog_array_map, u32 index)
+ * 	Description
+ * 		This special helper is used to trigger a "tail call", or in
+ * 		other words, to jump into another eBPF program. The same stack
+ * 		frame is used (but values on stack and in registers for the
+ * 		caller are not accessible to the callee). This mechanism allows
+ * 		for program chaining, either for raising the maximum number of
+ * 		available eBPF instructions, or to execute given programs in
+ * 		conditional blocks. For security reasons, there is an upper
+ * 		limit to the number of successive tail calls that can be
+ * 		performed.
+ *
+ * 		Upon call of this helper, the program attempts to jump into a
+ * 		program referenced at index *index* in *prog_array_map*, a
+ * 		special map of type **BPF_MAP_TYPE_PROG_ARRAY**, and passes
+ * 		*ctx*, a pointer to the context.
+ *
+ * 		If the call succeeds, the kernel immediately runs the first
+ * 		instruction of the new program. This is not a function call,
+ * 		and it never returns to the previous program. If the call
+ * 		fails, then the helper has no effect, and the caller continues
+ * 		to run its subsequent instructions. A call can fail if the
+ * 		destination program for the jump does not exist (i.e. *index*
+ * 		is superior to the number of entries in *prog_array_map*), or
+ * 		if the maximum number of tail calls has been reached for this
+ * 		chain of programs. This limit is defined in the kernel by the
+ * 		macro **MAX_TAIL_CALL_CNT** (not accessible to user space),
+ * 		which is currently set to 32.
+ * 	Return
+ * 		0 on success, or a negative error in case of failure.
+ *
+ * int bpf_clone_redirect(struct sk_buff *skb, u32 ifindex, u64 flags)
+ * 	Description
+ * 		Clone and redirect the packet associated to *skb* to another
+ * 		net device of index *ifindex*. Both ingress and egress
+ * 		interfaces can be used for redirection. The **BPF_F_INGRESS**
+ * 		value in *flags* is used to make the distinction (ingress path
+ * 		is selected if the flag is present, egress path otherwise).
+ * 		This is the only flag supported for now.
+ *
+ * 		In comparison with **bpf_redirect**\ () helper,
+ * 		**bpf_clone_redirect**\ () has the associated cost of
+ * 		duplicating the packet buffer, but this can be executed out of
+ * 		the eBPF program. Conversely, **bpf_redirect**\ () is more
+ * 		efficient, but it is handled through an action code where the
+ * 		redirection happens only after the eBPF program has returned.
+ *
+ * 		A call to this helper is susceptible to change the underlaying
+ * 		packet buffer. Therefore, at load time, all checks on pointers
+ * 		previously done by the verifier are invalidated and must be
+ * 		performed again, if the helper is used in combination with
+ * 		direct packet access.
+ * 	Return
+ * 		0 on success, or a negative error in case of failure.
  *
  * u64 bpf_get_current_pid_tgid(void)
- *     Return: current->tgid << 32 | current->pid
+ * 	Return
+ * 		A 64-bit integer containing the current tgid and pid, and
+ * 		created as such:
+ * 		*current_task*\ **->tgid << 32 \|**
+ * 		*current_task*\ **->pid**.
  *
  * u64 bpf_get_current_uid_gid(void)
- *     Return: current_gid << 32 | current_uid
- *
- * int bpf_get_current_comm(char *buf, int size_of_buf)
- *     stores current->comm into buf
- *     Return: 0 on success or negative error
- *
- * u32 bpf_get_cgroup_classid(skb)
- *     retrieve a proc's classid
- *     @skb: pointer to skb
- *     Return: classid if != 0
- *
- * int bpf_skb_vlan_push(skb, vlan_proto, vlan_tci)
- *     Return: 0 on success or negative error
- *
- * int bpf_skb_vlan_pop(skb)
- *     Return: 0 on success or negative error
- *
- * int bpf_skb_get_tunnel_key(skb, key, size, flags)
- * int bpf_skb_set_tunnel_key(skb, key, size, flags)
- *     retrieve or populate tunnel metadata
- *     @skb: pointer to skb
- *     @key: pointer to 'struct bpf_tunnel_key'
- *     @size: size of 'struct bpf_tunnel_key'
- *     @flags: room for future extensions
- *     Return: 0 on success or negative error
- *
- * u64 bpf_perf_event_read(map, flags)
- *     read perf event counter value
- *     @map: pointer to perf_event_array map
- *     @flags: index of event in the map or bitmask flags
- *     Return: value of perf event counter read or error code
- *
- * int bpf_redirect(ifindex, flags)
- *     redirect to another netdev
- *     @ifindex: ifindex of the net device
- *     @flags:
- *	  cls_bpf:
- *          bit 0 - if set, redirect to ingress instead of egress
- *          other bits - reserved
- *	  xdp_bpf:
- *	    all bits - reserved
- *     Return: cls_bpf: TC_ACT_REDIRECT on success or TC_ACT_SHOT on error
- *	       xdp_bfp: XDP_REDIRECT on success or XDP_ABORT on error
- * int bpf_redirect_map(map, key, flags)
- *     redirect to endpoint in map
- *     @map: pointer to dev map
- *     @key: index in map to lookup
- *     @flags: --
- *     Return: XDP_REDIRECT on success or XDP_ABORT on error
- *
- * u32 bpf_get_route_realm(skb)
- *     retrieve a dst's tclassid
- *     @skb: pointer to skb
- *     Return: realm if != 0
- *
- * int bpf_perf_event_output(ctx, map, flags, data, size)
- *     output perf raw sample
- *     @ctx: struct pt_regs*
- *     @map: pointer to perf_event_array map
- *     @flags: index of event in the map or bitmask flags
- *     @data: data on stack to be output as raw data
- *     @size: size of data
- *     Return: 0 on success or negative error
- *
- * int bpf_get_stackid(ctx, map, flags)
- *     walk user or kernel stack and return id
- *     @ctx: struct pt_regs*
- *     @map: pointer to stack_trace map
- *     @flags: bits 0-7 - numer of stack frames to skip
- *             bit 8 - collect user stack instead of kernel
- *             bit 9 - compare stacks by hash only
- *             bit 10 - if two different stacks hash into the same stackid
- *                      discard old
- *             other bits - reserved
- *     Return: >= 0 stackid on success or negative error
- *
- * s64 bpf_csum_diff(from, from_size, to, to_size, seed)
- *     calculate csum diff
- *     @from: raw from buffer
- *     @from_size: length of from buffer
- *     @to: raw to buffer
- *     @to_size: length of to buffer
- *     @seed: optional seed
- *     Return: csum result or negative error code
- *
- * int bpf_skb_get_tunnel_opt(skb, opt, size)
- *     retrieve tunnel options metadata
- *     @skb: pointer to skb
- *     @opt: pointer to raw tunnel option data
- *     @size: size of @opt
- *     Return: option size
- *
- * int bpf_skb_set_tunnel_opt(skb, opt, size)
- *     populate tunnel options metadata
- *     @skb: pointer to skb
- *     @opt: pointer to raw tunnel option data
- *     @size: size of @opt
- *     Return: 0 on success or negative error
- *
- * int bpf_skb_change_proto(skb, proto, flags)
- *     Change protocol of the skb. Currently supported is v4 -> v6,
- *     v6 -> v4 transitions. The helper will also resize the skb. eBPF
- *     program is expected to fill the new headers via skb_store_bytes
- *     and lX_csum_replace.
- *     @skb: pointer to skb
- *     @proto: new skb->protocol type
- *     @flags: reserved
- *     Return: 0 on success or negative error
- *
- * int bpf_skb_change_type(skb, type)
- *     Change packet type of skb.
- *     @skb: pointer to skb
- *     @type: new skb->pkt_type type
- *     Return: 0 on success or negative error
- *
- * int bpf_skb_under_cgroup(skb, map, index)
- *     Check cgroup2 membership of skb
- *     @skb: pointer to skb
- *     @map: pointer to bpf_map in BPF_MAP_TYPE_CGROUP_ARRAY type
- *     @index: index of the cgroup in the bpf_map
- *     Return:
- *       == 0 skb failed the cgroup2 descendant test
- *       == 1 skb succeeded the cgroup2 descendant test
- *        < 0 error
- *
- * u32 bpf_get_hash_recalc(skb)
- *     Retrieve and possibly recalculate skb->hash.
- *     @skb: pointer to skb
- *     Return: hash
+ * 	Return
+ * 		A 64-bit integer containing the current GID and UID, and
+ * 		created as such: *current_gid* **<< 32 \|** *current_uid*.
+ *
+ * int bpf_get_current_comm(char *buf, u32 size_of_buf)
+ * 	Description
+ * 		Copy the **comm** attribute of the current task into *buf* of
+ * 		*size_of_buf*. The **comm** attribute contains the name of
+ * 		the executable (excluding the path) for the current task. The
+ * 		*size_of_buf* must be strictly positive. On success, the
+ * 		helper makes sure that the *buf* is NUL-terminated. On failure,
+ * 		it is filled with zeroes.
+ * 	Return
+ * 		0 on success, or a negative error in case of failure.
+ *
+ * u32 bpf_get_cgroup_classid(struct sk_buff *skb)
+ * 	Description
+ * 		Retrieve the classid for the current task, i.e. for the net_cls
+ * 		cgroup to which *skb* belongs.
+ *
+ * 		This helper can be used on TC egress path, but not on ingress.
+ *
+ * 		The net_cls cgroup provides an interface to tag network packets
+ * 		based on a user-provided identifier for all traffic coming from
+ * 		the tasks belonging to the related cgroup. See also the related
+ * 		kernel documentation, available from the Linux sources in file
+ * 		*Documentation/cgroup-v1/net_cls.txt*.
+ *
+ * 		The Linux kernel has two versions for cgroups: there are
+ * 		cgroups v1 and cgroups v2. Both are available to users, who can
+ * 		use a mixture of them, but note that the net_cls cgroup is for
+ * 		cgroup v1 only. This makes it incompatible with BPF programs
+ * 		run on cgroups, which is a cgroup-v2-only feature (a socket can
+ * 		only hold data for one version of cgroups at a time).
+ *
+ * 		This helper is only available is the kernel was compiled with
+ * 		the **CONFIG_CGROUP_NET_CLASSID** configuration option set to
+ * 		"**y**" or to "**m**".
+ * 	Return
+ * 		The classid, or 0 for the default unconfigured classid.
+ *
+ * int bpf_skb_vlan_push(struct sk_buff *skb, __be16 vlan_proto, u16 vlan_tci)
+ * 	Description
+ * 		Push a *vlan_tci* (VLAN tag control information) of protocol
+ * 		*vlan_proto* to the packet associated to *skb*, then update
+ * 		the checksum. Note that if *vlan_proto* is different from
+ * 		**ETH_P_8021Q** and **ETH_P_8021AD**, it is considered to
+ * 		be **ETH_P_8021Q**.
+ *
+ * 		A call to this helper is susceptible to change the underlaying
+ * 		packet buffer. Therefore, at load time, all checks on pointers
+ * 		previously done by the verifier are invalidated and must be
+ * 		performed again, if the helper is used in combination with
+ * 		direct packet access.
+ * 	Return
+ * 		0 on success, or a negative error in case of failure.
+ *
+ * int bpf_skb_vlan_pop(struct sk_buff *skb)
+ * 	Description
+ * 		Pop a VLAN header from the packet associated to *skb*.
+ *
+ * 		A call to this helper is susceptible to change the underlaying
+ * 		packet buffer. Therefore, at load time, all checks on pointers
+ * 		previously done by the verifier are invalidated and must be
+ * 		performed again, if the helper is used in combination with
+ * 		direct packet access.
+ * 	Return
+ * 		0 on success, or a negative error in case of failure.
+ *
+ * int bpf_skb_get_tunnel_key(struct sk_buff *skb, struct bpf_tunnel_key *key, u32 size, u64 flags)
+ * 	Description
+ * 		Get tunnel metadata. This helper takes a pointer *key* to an
+ * 		empty **struct bpf_tunnel_key** of **size**, that will be
+ * 		filled with tunnel metadata for the packet associated to *skb*.
+ * 		The *flags* can be set to **BPF_F_TUNINFO_IPV6**, which
+ * 		indicates that the tunnel is based on IPv6 protocol instead of
+ * 		IPv4.
+ *
+ * 		The **struct bpf_tunnel_key** is an object that generalizes the
+ * 		principal parameters used by various tunneling protocols into a
+ * 		single struct. This way, it can be used to easily make a
+ * 		decision based on the contents of the encapsulation header,
+ * 		"summarized" in this struct. In particular, it holds the IP
+ * 		address of the remote end (IPv4 or IPv6, depending on the case)
+ * 		in *key*\ **->remote_ipv4** or *key*\ **->remote_ipv6**. Also,
+ * 		this struct exposes the *key*\ **->tunnel_id**, which is
+ * 		generally mapped to a VNI (Virtual Network Identifier), making
+ * 		it programmable together with the **bpf_skb_set_tunnel_key**\
+ * 		() helper.
+ *
+ * 		Let's imagine that the following code is part of a program
+ * 		attached to the TC ingress interface, on one end of a GRE
+ * 		tunnel, and is supposed to filter out all messages coming from
+ * 		remote ends with IPv4 address other than 10.0.0.1:
+ *
+ * 		::
+ *
+ * 			int ret;
+ * 			struct bpf_tunnel_key key = {};
+ * 			
+ * 			ret = bpf_skb_get_tunnel_key(skb, &key, sizeof(key), 0);
+ * 			if (ret < 0)
+ * 				return TC_ACT_SHOT;	// drop packet
+ * 			
+ * 			if (key.remote_ipv4 != 0x0a000001)
+ * 				return TC_ACT_SHOT;	// drop packet
+ * 			
+ * 			return TC_ACT_OK;		// accept packet
+ *
+ * 		This interface can also be used with all encapsulation devices
+ * 		that can operate in "collect metadata" mode: instead of having
+ * 		one network device per specific configuration, the "collect
+ * 		metadata" mode only requires a single device where the
+ * 		configuration can be extracted from this helper.
+ *
+ * 		This can be used together with various tunnels such as VXLan,
+ * 		Geneve, GRE or IP in IP (IPIP).
+ * 	Return
+ * 		0 on success, or a negative error in case of failure.
+ *
+ * int bpf_skb_set_tunnel_key(struct sk_buff *skb, struct bpf_tunnel_key *key, u32 size, u64 flags)
+ * 	Description
+ * 		Populate tunnel metadata for packet associated to *skb.* The
+ * 		tunnel metadata is set to the contents of *key*, of *size*. The
+ * 		*flags* can be set to a combination of the following values:
+ *
+ * 		**BPF_F_TUNINFO_IPV6**
+ * 			Indicate that the tunnel is based on IPv6 protocol
+ * 			instead of IPv4.
+ * 		**BPF_F_ZERO_CSUM_TX**
+ * 			For IPv4 packets, add a flag to tunnel metadata
+ * 			indicating that checksum computation should be skipped
+ * 			and checksum set to zeroes.
+ * 		**BPF_F_DONT_FRAGMENT**
+ * 			Add a flag to tunnel metadata indicating that the
+ * 			packet should not be fragmented.
+ * 		**BPF_F_SEQ_NUMBER**
+ * 			Add a flag to tunnel metadata indicating that a
+ * 			sequence number should be added to tunnel header before
+ * 			sending the packet. This flag was added for GRE
+ * 			encapsulation, but might be used with other protocols
+ * 			as well in the future.
+ *
+ * 		Here is a typical usage on the transmit path:
+ *
+ * 		::
+ *
+ * 			struct bpf_tunnel_key key;
+ * 			     populate key ...
+ * 			bpf_skb_set_tunnel_key(skb, &key, sizeof(key), 0);
+ * 			bpf_clone_redirect(skb, vxlan_dev_ifindex, 0);
+ *
+ * 		See also the description of the **bpf_skb_get_tunnel_key**\ ()
+ * 		helper for additional information.
+ * 	Return
+ * 		0 on success, or a negative error in case of failure.
+ *
+ * u64 bpf_perf_event_read(struct bpf_map *map, u64 flags)
+ * 	Description
+ * 		Read the value of a perf event counter. This helper relies on a
+ * 		*map* of type **BPF_MAP_TYPE_PERF_EVENT_ARRAY**. The nature of
+ * 		the perf event counter is selected when *map* is updated with
+ * 		perf event file descriptors. The *map* is an array whose size
+ * 		is the number of available CPUs, and each cell contains a value
+ * 		relative to one CPU. The value to retrieve is indicated by
+ * 		*flags*, that contains the index of the CPU to look up, masked
+ * 		with **BPF_F_INDEX_MASK**. Alternatively, *flags* can be set to
+ * 		**BPF_F_CURRENT_CPU** to indicate that the value for the
+ * 		current CPU should be retrieved.
+ *
+ * 		Note that before Linux 4.13, only hardware perf event can be
+ * 		retrieved.
+ *
+ * 		Also, be aware that the newer helper
+ * 		**bpf_perf_event_read_value**\ () is recommended over
+ * 		**bpf_perf_event_read*\ () in general. The latter has some ABI
+ * 		quirks where error and counter value are used as a return code
+ * 		(which is wrong to do since ranges may overlap). This issue is
+ * 		fixed with bpf_perf_event_read_value(), which at the same time
+ * 		provides more features over the **bpf_perf_event_read**\ ()
+ * 		interface. Please refer to the description of
+ * 		**bpf_perf_event_read_value**\ () for details.
+ * 	Return
+ * 		The value of the perf event counter read from the map, or a
+ * 		negative error code in case of failure.
+ *
+ * int bpf_redirect(u32 ifindex, u64 flags)
+ * 	Description
+ * 		Redirect the packet to another net device of index *ifindex*.
+ * 		This helper is somewhat similar to **bpf_clone_redirect**\
+ * 		(), except that the packet is not cloned, which provides
+ * 		increased performance.
+ *
+ * 		Except for XDP, both ingress and egress interfaces can be used
+ * 		for redirection. The **BPF_F_INGRESS** value in *flags* is used
+ * 		to make the distinction (ingress path is selected if the flag
+ * 		is present, egress path otherwise). Currently, XDP only
+ * 		supports redirection to the egress interface, and accepts no
+ * 		flag at all.
+ *
+ * 		The same effect can be attained with the more generic
+ * 		**bpf_redirect_map**\ (), which requires specific maps to be
+ * 		used but offers better performance.
+ * 	Return
+ * 		For XDP, the helper returns **XDP_REDIRECT** on success or
+ * 		**XDP_ABORTED** on error. For other program types, the values
+ * 		are **TC_ACT_REDIRECT** on success or **TC_ACT_SHOT** on
+ * 		error.
+ *
+ * u32 bpf_get_route_realm(struct sk_buff *skb)
+ * 	Description
+ * 		Retrieve the realm or the route, that is to say the
+ * 		**tclassid** field of the destination for the *skb*. The
+ * 		indentifier retrieved is a user-provided tag, similar to the
+ * 		one used with the net_cls cgroup (see description for
+ * 		**bpf_get_cgroup_classid**\ () helper), but here this tag is
+ * 		held by a route (a destination entry), not by a task.
+ *
+ * 		Retrieving this identifier works with the clsact TC egress hook
+ * 		(see also **tc-bpf(8)**), or alternatively on conventional
+ * 		classful egress qdiscs, but not on TC ingress path. In case of
+ * 		clsact TC egress hook, this has the advantage that, internally,
+ * 		the destination entry has not been dropped yet in the transmit
+ * 		path. Therefore, the destination entry does not need to be
+ * 		artificially held via **netif_keep_dst**\ () for a classful
+ * 		qdisc until the *skb* is freed.
+ *
+ * 		This helper is available only if the kernel was compiled with
+ * 		**CONFIG_IP_ROUTE_CLASSID** configuration option.
+ * 	Return
+ * 		The realm of the route for the packet associated to *skb*, or 0
+ * 		if none was found.
+ *
+ * int bpf_perf_event_output(struct pt_reg *ctx, struct bpf_map *map, u64 flags, void *data, u64 size)
+ * 	Description
+ * 		Write raw *data* blob into a special BPF perf event held by
+ * 		*map* of type **BPF_MAP_TYPE_PERF_EVENT_ARRAY**. This perf
+ * 		event must have the following attributes: **PERF_SAMPLE_RAW**
+ * 		as **sample_type**, **PERF_TYPE_SOFTWARE** as **type**, and
+ * 		**PERF_COUNT_SW_BPF_OUTPUT** as **config**.
+ *
+ * 		The *flags* are used to indicate the index in *map* for which
+ * 		the value must be put, masked with **BPF_F_INDEX_MASK**.
+ * 		Alternatively, *flags* can be set to **BPF_F_CURRENT_CPU**
+ * 		to indicate that the index of the current CPU core should be
+ * 		used.
+ *
+ * 		The value to write, of *size*, is passed through eBPF stack and
+ * 		pointed by *data*.
+ *
+ * 		The context of the program *ctx* needs also be passed to the
+ * 		helper.
+ *
+ * 		On user space, a program willing to read the values needs to
+ * 		call **perf_event_open**\ () on the perf event (either for
+ * 		one or for all CPUs) and to store the file descriptor into the
+ * 		*map*. This must be done before the eBPF program can send data
+ * 		into it. An example is available in file
+ * 		*samples/bpf/trace_output_user.c* in the Linux kernel source
+ * 		tree (the eBPF program counterpart is in
+ * 		*samples/bpf/trace_output_kern.c*).
+ *
+ * 		**bpf_perf_event_output**\ () achieves better performance
+ * 		than **bpf_trace_printk**\ () for sharing data with user
+ * 		space, and is much better suitable for streaming data from eBPF
+ * 		programs.
+ *
+ * 		Note that this helper is not restricted to tracing use cases
+ * 		and can be used with programs attached to TC or XDP as well,
+ * 		where it allows for passing data to user space listeners. Data
+ * 		can be:
+ *
+ * 		* Only custom structs,
+ * 		* Only the packet payload, or
+ * 		* A combination of both.
+ * 	Return
+ * 		0 on success, or a negative error in case of failure.
+ *
+ * int bpf_skb_load_bytes(const struct sk_buff *skb, u32 offset, void *to, u32 len)
+ * 	Description
+ * 		This helper was provided as an easy way to load data from a
+ * 		packet. It can be used to load *len* bytes from *offset* from
+ * 		the packet associated to *skb*, into the buffer pointed by
+ * 		*to*.
+ *
+ * 		Since Linux 4.7, usage of this helper has mostly been replaced
+ * 		by "direct packet access", enabling packet data to be
+ * 		manipulated with *skb*\ **->data** and *skb*\ **->data_end**
+ * 		pointing respectively to the first byte of packet data and to
+ * 		the byte after the last byte of packet data. However, it
+ * 		remains useful if one wishes to read large quantities of data
+ * 		at once from a packet into the eBPF stack.
+ * 	Return
+ * 		0 on success, or a negative error in case of failure.
+ *
+ * int bpf_get_stackid(struct pt_reg *ctx, struct bpf_map *map, u64 flags)
+ * 	Description
+ * 		Walk a user or a kernel stack and return its id. To achieve
+ * 		this, the helper needs *ctx*, which is a pointer to the context
+ * 		on which the tracing program is executed, and a pointer to a
+ * 		*map* of type **BPF_MAP_TYPE_STACK_TRACE**.
+ *
+ * 		The last argument, *flags*, holds the number of stack frames to
+ * 		skip (from 0 to 255), masked with
+ * 		**BPF_F_SKIP_FIELD_MASK**. The next bits can be used to set
+ * 		a combination of the following flags:
+ *
+ * 		**BPF_F_USER_STACK**
+ * 			Collect a user space stack instead of a kernel stack.
+ * 		**BPF_F_FAST_STACK_CMP**
+ * 			Compare stacks by hash only.
+ * 		**BPF_F_REUSE_STACKID**
+ * 			If two different stacks hash into the same *stackid*,
+ * 			discard the old one.
+ *
+ * 		The stack id retrieved is a 32 bit long integer handle which
+ * 		can be further combined with other data (including other stack
+ * 		ids) and used as a key into maps. This can be useful for
+ * 		generating a variety of graphs (such as flame graphs or off-cpu
+ * 		graphs).
+ *
+ * 		For walking a stack, this helper is an improvement over
+ * 		**bpf_probe_read**\ (), which can be used with unrolled loops
+ * 		but is not efficient and consumes a lot of eBPF instructions.
+ * 		Instead, **bpf_get_stackid**\ () can collect up to
+ * 		**PERF_MAX_STACK_DEPTH** both kernel and user frames. Note that
+ * 		this limit can be controlled with the **sysctl** program, and
+ * 		that it should be manually increased in order to profile long
+ * 		user stacks (such as stacks for Java programs). To do so, use:
+ *
+ * 		::
+ *
+ * 			# sysctl kernel.perf_event_max_stack=<new value>
+ *
+ * 	Return
+ * 		The positive or null stack id on success, or a negative error
+ * 		in case of failure.
+ *
+ * s64 bpf_csum_diff(__be32 *from, u32 from_size, __be32 *to, u32 to_size, __wsum seed)
+ * 	Description
+ * 		Compute a checksum difference, from the raw buffer pointed by
+ * 		*from*, of length *from_size* (that must be a multiple of 4),
+ * 		towards the raw buffer pointed by *to*, of size *to_size*
+ * 		(same remark). An optional *seed* can be added to the value
+ * 		(this can be cascaded, the seed may come from a previous call
+ * 		to the helper).
+ *
+ * 		This is flexible enough to be used in several ways:
+ *
+ * 		* With *from_size* == 0, *to_size* > 0 and *seed* set to
+ * 		  checksum, it can be used when pushing new data.
+ * 		* With *from_size* > 0, *to_size* == 0 and *seed* set to
+ * 		  checksum, it can be used when removing data from a packet.
+ * 		* With *from_size* > 0, *to_size* > 0 and *seed* set to 0, it
+ * 		  can be used to compute a diff. Note that *from_size* and
+ * 		  *to_size* do not need to be equal.
+ *
+ * 		This helper can be used in combination with
+ * 		**bpf_l3_csum_replace**\ () and **bpf_l4_csum_replace**\ (), to
+ * 		which one can feed in the difference computed with
+ * 		**bpf_csum_diff**\ ().
+ * 	Return
+ * 		The checksum result, or a negative error code in case of
+ * 		failure.
+ *
+ * int bpf_skb_get_tunnel_opt(struct sk_buff *skb, u8 *opt, u32 size)
+ * 	Description
+ * 		Retrieve tunnel options metadata for the packet associated to
+ * 		*skb*, and store the raw tunnel option data to the buffer *opt*
+ * 		of *size*.
+ *
+ * 		This helper can be used with encapsulation devices that can
+ * 		operate in "collect metadata" mode (please refer to the related
+ * 		note in the description of **bpf_skb_get_tunnel_key**\ () for
+ * 		more details). A particular example where this can be used is
+ * 		in combination with the Geneve encapsulation protocol, where it
+ * 		allows for pushing (with **bpf_skb_get_tunnel_opt**\ () helper)
+ * 		and retrieving arbitrary TLVs (Type-Length-Value headers) from
+ * 		the eBPF program. This allows for full customization of these
+ * 		headers.
+ * 	Return
+ * 		The size of the option data retrieved.
+ *
+ * int bpf_skb_set_tunnel_opt(struct sk_buff *skb, u8 *opt, u32 size)
+ * 	Description
+ * 		Set tunnel options metadata for the packet associated to *skb*
+ * 		to the option data contained in the raw buffer *opt* of *size*.
+ *
+ * 		See also the description of the **bpf_skb_get_tunnel_opt**\ ()
+ * 		helper for additional information.
+ * 	Return
+ * 		0 on success, or a negative error in case of failure.
+ *
+ * int bpf_skb_change_proto(struct sk_buff *skb, __be16 proto, u64 flags)
+ * 	Description
+ * 		Change the protocol of the *skb* to *proto*. Currently
+ * 		supported are transition from IPv4 to IPv6, and from IPv6 to
+ * 		IPv4. The helper takes care of the groundwork for the
+ * 		transition, including resizing the socket buffer. The eBPF
+ * 		program is expected to fill the new headers, if any, via
+ * 		**skb_store_bytes**\ () and to recompute the checksums with
+ * 		**bpf_l3_csum_replace**\ () and **bpf_l4_csum_replace**\
+ * 		(). The main case for this helper is to perform NAT64
+ * 		operations out of an eBPF program.
+ *
+ * 		Internally, the GSO type is marked as dodgy so that headers are
+ * 		checked and segments are recalculated by the GSO/GRO engine.
+ * 		The size for GSO target is adapted as well.
+ *
+ * 		All values for *flags* are reserved for future usage, and must
+ * 		be left at zero.
+ *
+ * 		A call to this helper is susceptible to change the underlaying
+ * 		packet buffer. Therefore, at load time, all checks on pointers
+ * 		previously done by the verifier are invalidated and must be
+ * 		performed again, if the helper is used in combination with
+ * 		direct packet access.
+ * 	Return
+ * 		0 on success, or a negative error in case of failure.
+ *
+ * int bpf_skb_change_type(struct sk_buff *skb, u32 type)
+ * 	Description
+ * 		Change the packet type for the packet associated to *skb*. This
+ * 		comes down to setting *skb*\ **->pkt_type** to *type*, except
+ * 		the eBPF program does not have a write access to *skb*\
+ * 		**->pkt_type** beside this helper. Using a helper here allows
+ * 		for graceful handling of errors.
+ *
+ * 		The major use case is to change incoming *skb*s to
+ * 		**PACKET_HOST** in a programmatic way instead of having to
+ * 		recirculate via **redirect**\ (..., **BPF_F_INGRESS**), for
+ * 		example.
+ *
+ * 		Note that *type* only allows certain values. At this time, they
+ * 		are:
+ *
+ * 		**PACKET_HOST**
+ * 			Packet is for us.
+ * 		**PACKET_BROADCAST**
+ * 			Send packet to all.
+ * 		**PACKET_MULTICAST**
+ * 			Send packet to group.
+ * 		**PACKET_OTHERHOST**
+ * 			Send packet to someone else.
+ * 	Return
+ * 		0 on success, or a negative error in case of failure.
+ *
+ * int bpf_skb_under_cgroup(struct sk_buff *skb, struct bpf_map *map, u32 index)
+ * 	Description
+ * 		Check whether *skb* is a descendant of the cgroup2 held by
+ * 		*map* of type **BPF_MAP_TYPE_CGROUP_ARRAY**, at *index*.
+ * 	Return
+ * 		The return value depends on the result of the test, and can be:
+ *
+ * 		* 0, if the *skb* failed the cgroup2 descendant test.
+ * 		* 1, if the *skb* succeeded the cgroup2 descendant test.
+ * 		* A negative error code, if an error occurred.
+ *
+ * u32 bpf_get_hash_recalc(struct sk_buff *skb)
+ * 	Description
+ * 		Retrieve the hash of the packet, *skb*\ **->hash**. If it is
+ * 		not set, in particular if the hash was cleared due to mangling,
+ * 		recompute this hash. Later accesses to the hash can be done
+ * 		directly with *skb*\ **->hash**.
+ *
+ * 		Calling **bpf_set_hash_invalid**\ (), changing a packet
+ * 		prototype with **bpf_skb_change_proto**\ (), or calling
+ * 		**bpf_skb_store_bytes**\ () with the
+ * 		**BPF_F_INVALIDATE_HASH** are actions susceptible to clear
+ * 		the hash and to trigger a new computation for the next call to
+ * 		**bpf_get_hash_recalc**\ ().
+ * 	Return
+ * 		The 32-bit hash.
  *
  * u64 bpf_get_current_task(void)
- *     Returns current task_struct
- *     Return: current
- *
- * int bpf_probe_write_user(void *dst, void *src, int len)
- *     safely attempt to write to a location
- *     @dst: destination address in userspace
- *     @src: source address on stack
- *     @len: number of bytes to copy
- *     Return: 0 on success or negative error
- *
- * int bpf_current_task_under_cgroup(map, index)
- *     Check cgroup2 membership of current task
- *     @map: pointer to bpf_map in BPF_MAP_TYPE_CGROUP_ARRAY type
- *     @index: index of the cgroup in the bpf_map
- *     Return:
- *       == 0 current failed the cgroup2 descendant test
- *       == 1 current succeeded the cgroup2 descendant test
- *        < 0 error
- *
- * int bpf_skb_change_tail(skb, len, flags)
- *     The helper will resize the skb to the given new size, to be used f.e.
- *     with control messages.
- *     @skb: pointer to skb
- *     @len: new skb length
- *     @flags: reserved
- *     Return: 0 on success or negative error
- *
- * int bpf_skb_pull_data(skb, len)
- *     The helper will pull in non-linear data in case the skb is non-linear
- *     and not all of len are part of the linear section. Only needed for
- *     read/write with direct packet access.
- *     @skb: pointer to skb
- *     @len: len to make read/writeable
- *     Return: 0 on success or negative error
- *
- * s64 bpf_csum_update(skb, csum)
- *     Adds csum into skb->csum in case of CHECKSUM_COMPLETE.
- *     @skb: pointer to skb
- *     @csum: csum to add
- *     Return: csum on success or negative error
- *
- * void bpf_set_hash_invalid(skb)
- *     Invalidate current skb->hash.
- *     @skb: pointer to skb
- *
- * int bpf_get_numa_node_id()
- *     Return: Id of current NUMA node.
- *
- * int bpf_skb_change_head()
- *     Grows headroom of skb and adjusts MAC header offset accordingly.
- *     Will extends/reallocae as required automatically.
- *     May change skb data pointer and will thus invalidate any check
- *     performed for direct packet access.
- *     @skb: pointer to skb
- *     @len: length of header to be pushed in front
- *     @flags: Flags (unused for now)
- *     Return: 0 on success or negative error
- *
- * int bpf_xdp_adjust_head(xdp_md, delta)
- *     Adjust the xdp_md.data by delta
- *     @xdp_md: pointer to xdp_md
- *     @delta: An positive/negative integer to be added to xdp_md.data
- *     Return: 0 on success or negative on error
+ * 	Return
+ * 		A pointer to the current task struct.
+ *
+ * int bpf_probe_write_user(void *dst, const void *src, u32 len)
+ * 	Description
+ * 		Attempt in a safe way to write *len* bytes from the buffer
+ * 		*src* to *dst* in memory. It only works for threads that are in
+ * 		user context, and *dst* must be a valid user space address.
+ *
+ * 		This helper should not be used to implement any kind of
+ * 		security mechanism because of TOC-TOU attacks, but rather to
+ * 		debug, divert, and manipulate execution of semi-cooperative
+ * 		processes.
+ *
+ * 		Keep in mind that this feature is meant for experiments, and it
+ * 		has a risk of crashing the system and running programs.
+ * 		Therefore, when an eBPF program using this helper is attached,
+ * 		a warning including PID and process name is printed to kernel
+ * 		logs.
+ * 	Return
+ * 		0 on success, or a negative error in case of failure.
+ *
+ * int bpf_current_task_under_cgroup(struct bpf_map *map, u32 index)
+ * 	Description
+ * 		Check whether the probe is being run is the context of a given
+ * 		subset of the cgroup2 hierarchy. The cgroup2 to test is held by
+ * 		*map* of type **BPF_MAP_TYPE_CGROUP_ARRAY**, at *index*.
+ * 	Return
+ * 		The return value depends on the result of the test, and can be:
+ *
+ * 		* 0, if the *skb* task belongs to the cgroup2.
+ * 		* 1, if the *skb* task does not belong to the cgroup2.
+ * 		* A negative error code, if an error occurred.
+ *
+ * int bpf_skb_change_tail(struct sk_buff *skb, u32 len, u64 flags)
+ * 	Description
+ * 		Resize (trim or grow) the packet associated to *skb* to the
+ * 		new *len*. The *flags* are reserved for future usage, and must
+ * 		be left at zero.
+ *
+ * 		The basic idea is that the helper performs the needed work to
+ * 		change the size of the packet, then the eBPF program rewrites
+ * 		the rest via helpers like **bpf_skb_store_bytes**\ (),
+ * 		**bpf_l3_csum_replace**\ (), **bpf_l3_csum_replace**\ ()
+ * 		and others. This helper is a slow path utility intended for
+ * 		replies with control messages. And because it is targeted for
+ * 		slow path, the helper itself can afford to be slow: it
+ * 		implicitly linearizes, unclones and drops offloads from the
+ * 		*skb*.
+ *
+ * 		A call to this helper is susceptible to change the underlaying
+ * 		packet buffer. Therefore, at load time, all checks on pointers
+ * 		previously done by the verifier are invalidated and must be
+ * 		performed again, if the helper is used in combination with
+ * 		direct packet access.
+ * 	Return
+ * 		0 on success, or a negative error in case of failure.
+ *
+ * int bpf_skb_pull_data(struct sk_buff *skb, u32 len)
+ * 	Description
+ * 		Pull in non-linear data in case the *skb* is non-linear and not
+ * 		all of *len* are part of the linear section. Make *len* bytes
+ * 		from *skb* readable and writable. If a zero value is passed for
+ * 		*len*, then the whole length of the *skb* is pulled.
+ *
+ * 		This helper is only needed for reading and writing with direct
+ * 		packet access.
+ *
+ * 		For direct packet access, testing that offsets to access
+ * 		are within packet boundaries (test on *skb*\ **->data_end**) is
+ * 		susceptible to fail if offsets are invalid, or if the requested
+ * 		data is in non-linear parts of the *skb*. On failure the
+ * 		program can just bail out, or in the case of a non-linear
+ * 		buffer, use a helper to make the data available. The
+ * 		**bpf_skb_load_bytes**\ () helper is a first solution to access
+ * 		the data. Another one consists in using **bpf_skb_pull_data**
+ * 		to pull in once the non-linear parts, then retesting and
+ * 		eventually access the data.
+ *
+ * 		At the same time, this also makes sure the *skb* is uncloned,
+ * 		which is a necessary condition for direct write. As this needs
+ * 		to be an invariant for the write part only, the verifier
+ * 		detects writes and adds a prologue that is calling
+ * 		**bpf_skb_pull_data()** to effectively unclone the *skb* from
+ * 		the very beginning in case it is indeed cloned.
+ *
+ * 		A call to this helper is susceptible to change the underlaying
+ * 		packet buffer. Therefore, at load time, all checks on pointers
+ * 		previously done by the verifier are invalidated and must be
+ * 		performed again, if the helper is used in combination with
+ * 		direct packet access.
+ * 	Return
+ * 		0 on success, or a negative error in case of failure.
+ *
+ * s64 bpf_csum_update(struct sk_buff *skb, __wsum csum)
+ * 	Description
+ * 		Add the checksum *csum* into *skb*\ **->csum** in case the
+ * 		driver has supplied a checksum for the entire packet into that
+ * 		field. Return an error otherwise. This helper is intended to be
+ * 		used in combination with **bpf_csum_diff**\ (), in particular
+ * 		when the checksum needs to be updated after data has been
+ * 		written into the packet through direct packet access.
+ * 	Return
+ * 		The checksum on success, or a negative error code in case of
+ * 		failure.
+ *
+ * void bpf_set_hash_invalid(struct sk_buff *skb)
+ * 	Description
+ * 		Invalidate the current *skb*\ **->hash**. It can be used after
+ * 		mangling on headers through direct packet access, in order to
+ * 		indicate that the hash is outdated and to trigger a
+ * 		recalculation the next time the kernel tries to access this
+ * 		hash or when the **bpf_get_hash_recalc**\ () helper is called.
+ *
+ * int bpf_get_numa_node_id(void)
+ * 	Description
+ * 		Return the id of the current NUMA node. The primary use case
+ * 		for this helper is the selection of sockets for the local NUMA
+ * 		node, when the program is attached to sockets using the
+ * 		**SO_ATTACH_REUSEPORT_EBPF** option (see also **socket(7)**),
+ * 		but the helper is also available to other eBPF program types,
+ * 		similarly to **bpf_get_smp_processor_id**\ ().
+ * 	Return
+ * 		The id of current NUMA node.
+ *
+ * int bpf_skb_change_head(struct sk_buff *skb, u32 len, u64 flags)
+ * 	Description
+ * 		Grows headroom of packet associated to *skb* and adjusts the
+ * 		offset of the MAC header accordingly, adding *len* bytes of
+ * 		space. It automatically extends and reallocates memory as
+ * 		required.
+ *
+ * 		This helper can be used on a layer 3 *skb* to push a MAC header
+ * 		for redirection into a layer 2 device.
+ *
+ * 		All values for *flags* are reserved for future usage, and must
+ * 		be left at zero.
+ *
+ * 		A call to this helper is susceptible to change the underlaying
+ * 		packet buffer. Therefore, at load time, all checks on pointers
+ * 		previously done by the verifier are invalidated and must be
+ * 		performed again, if the helper is used in combination with
+ * 		direct packet access.
+ * 	Return
+ * 		0 on success, or a negative error in case of failure.
+ *
+ * int bpf_xdp_adjust_head(struct xdp_buff *xdp_md, int delta)
+ * 	Description
+ * 		Adjust (move) *xdp_md*\ **->data** by *delta* bytes. Note that
+ * 		it is possible to use a negative value for *delta*. This helper
+ * 		can be used to prepare the packet for pushing or popping
+ * 		headers.
+ *
+ * 		A call to this helper is susceptible to change the underlaying
+ * 		packet buffer. Therefore, at load time, all checks on pointers
+ * 		previously done by the verifier are invalidated and must be
+ * 		performed again, if the helper is used in combination with
+ * 		direct packet access.
+ * 	Return
+ * 		0 on success, or a negative error in case of failure.
  *
  * int bpf_probe_read_str(void *dst, int size, const void *unsafe_ptr)
- *     Copy a NUL terminated string from unsafe address. In case the string
- *     length is smaller than size, the target is not padded with further NUL
- *     bytes. In case the string length is larger than size, just count-1
- *     bytes are copied and the last byte is set to NUL.
- *     @dst: destination address
- *     @size: maximum number of bytes to copy, including the trailing NUL
- *     @unsafe_ptr: unsafe address
- *     Return:
- *       > 0 length of the string including the trailing NUL on success
- *       < 0 error
- *
- * u64 bpf_get_socket_cookie(skb)
- *     Get the cookie for the socket stored inside sk_buff.
- *     @skb: pointer to skb
- *     Return: 8 Bytes non-decreasing number on success or 0 if the socket
- *     field is missing inside sk_buff
- *
- * u32 bpf_get_socket_uid(skb)
- *     Get the owner uid of the socket stored inside sk_buff.
- *     @skb: pointer to skb
- *     Return: uid of the socket owner on success or overflowuid if failed.
- *
- * u32 bpf_set_hash(skb, hash)
- *     Set full skb->hash.
- *     @skb: pointer to skb
- *     @hash: hash to set
- *
- * int bpf_setsockopt(bpf_socket, level, optname, optval, optlen)
- *     Calls setsockopt. Not all opts are available, only those with
- *     integer optvals plus TCP_CONGESTION.
- *     Supported levels: SOL_SOCKET and IPPROTO_TCP
- *     @bpf_socket: pointer to bpf_socket
- *     @level: SOL_SOCKET or IPPROTO_TCP
- *     @optname: option name
- *     @optval: pointer to option value
- *     @optlen: length of optval in bytes
- *     Return: 0 or negative error
- *
- * int bpf_getsockopt(bpf_socket, level, optname, optval, optlen)
- *     Calls getsockopt. Not all opts are available.
- *     Supported levels: IPPROTO_TCP
- *     @bpf_socket: pointer to bpf_socket
- *     @level: IPPROTO_TCP
- *     @optname: option name
- *     @optval: pointer to option value
- *     @optlen: length of optval in bytes
- *     Return: 0 or negative error
- *
- * int bpf_sock_ops_cb_flags_set(bpf_sock_ops, flags)
- *     Set callback flags for sock_ops
- *     @bpf_sock_ops: pointer to bpf_sock_ops_kern struct
- *     @flags: flags value
- *     Return: 0 for no error
- *             -EINVAL if there is no full tcp socket
- *             bits in flags that are not supported by current kernel
- *
- * int bpf_skb_adjust_room(skb, len_diff, mode, flags)
- *     Grow or shrink room in sk_buff.
- *     @skb: pointer to skb
- *     @len_diff: (signed) amount of room to grow/shrink
- *     @mode: operation mode (enum bpf_adj_room_mode)
- *     @flags: reserved for future use
- *     Return: 0 on success or negative error code
- *
- * int bpf_sk_redirect_map(map, key, flags)
- *     Redirect skb to a sock in map using key as a lookup key for the
- *     sock in map.
- *     @map: pointer to sockmap
- *     @key: key to lookup sock in map
- *     @flags: reserved for future use
- *     Return: SK_PASS
- *
- * int bpf_sock_map_update(skops, map, key, flags)
- *	@skops: pointer to bpf_sock_ops
- *	@map: pointer to sockmap to update
- *	@key: key to insert/update sock in map
- *	@flags: same flags as map update elem
- *
- * int bpf_xdp_adjust_meta(xdp_md, delta)
- *     Adjust the xdp_md.data_meta by delta
- *     @xdp_md: pointer to xdp_md
- *     @delta: An positive/negative integer to be added to xdp_md.data_meta
- *     Return: 0 on success or negative on error
- *
- * int bpf_perf_event_read_value(map, flags, buf, buf_size)
- *     read perf event counter value and perf event enabled/running time
- *     @map: pointer to perf_event_array map
- *     @flags: index of event in the map or bitmask flags
- *     @buf: buf to fill
- *     @buf_size: size of the buf
- *     Return: 0 on success or negative error code
- *
- * int bpf_perf_prog_read_value(ctx, buf, buf_size)
- *     read perf prog attached perf event counter and enabled/running time
- *     @ctx: pointer to ctx
- *     @buf: buf to fill
- *     @buf_size: size of the buf
- *     Return : 0 on success or negative error code
- *
- * int bpf_override_return(pt_regs, rc)
- *	@pt_regs: pointer to struct pt_regs
- *	@rc: the return value to set
- *
- * int bpf_msg_redirect_map(map, key, flags)
- *     Redirect msg to a sock in map using key as a lookup key for the
- *     sock in map.
- *     @map: pointer to sockmap
- *     @key: key to lookup sock in map
- *     @flags: reserved for future use
- *     Return: SK_PASS
- *
- * int bpf_bind(ctx, addr, addr_len)
- *     Bind socket to address. Only binding to IP is supported, no port can be
- *     set in addr.
- *     @ctx: pointer to context of type bpf_sock_addr
- *     @addr: pointer to struct sockaddr to bind socket to
- *     @addr_len: length of sockaddr structure
- *     Return: 0 on success or negative error code
- *
- * int bpf_xdp_adjust_tail(xdp_md, delta)
- *     Adjust the xdp_md.data_end by delta. Only shrinking of packet's
- *     size is supported.
- *     @xdp_md: pointer to xdp_md
- *     @delta: A negative integer to be added to xdp_md.data_end
- *     Return: 0 on success or negative on error
+ * 	Description
+ * 		Copy a NUL terminated string from an unsafe address
+ * 		*unsafe_ptr* to *dst*. The *size* should include the
+ * 		terminating NUL byte. In case the string length is smaller than
+ * 		*size*, the target is not padded with further NUL bytes. If the
+ * 		string length is larger than *size*, just *size*-1 bytes are
+ * 		copied and the last byte is set to NUL.
+ *
+ * 		On success, the length of the copied string is returned. This
+ * 		makes this helper useful in tracing programs for reading
+ * 		strings, and more importantly to get its length at runtime. See
+ * 		the following snippet:
+ *
+ * 		::
+ *
+ * 			SEC("kprobe/sys_open")
+ * 			void bpf_sys_open(struct pt_regs *ctx)
+ * 			{
+ * 			        char buf[PATHLEN]; // PATHLEN is defined to 256
+ * 			        int res = bpf_probe_read_str(buf, sizeof(buf),
+ * 				                             ctx->di);
+ *
+ * 				// Consume buf, for example push it to
+ * 				// userspace via bpf_perf_event_output(); we
+ * 				// can use res (the string length) as event
+ * 				// size, after checking its boundaries.
+ * 			}
+ *
+ * 		In comparison, using **bpf_probe_read()** helper here instead
+ * 		to read the string would require to estimate the length at
+ * 		compile time, and would often result in copying more memory
+ * 		than necessary.
+ *
+ * 		Another useful use case is when parsing individual process
+ * 		arguments or individual environment variables navigating
+ * 		*current*\ **->mm->arg_start** and *current*\
+ * 		**->mm->env_start**: using this helper and the return value,
+ * 		one can quickly iterate at the right offset of the memory area.
+ * 	Return
+ * 		On success, the strictly positive length of the string,
+ * 		including the trailing NUL character. On error, a negative
+ * 		value.
+ *
+ * u64 bpf_get_socket_cookie(struct sk_buff *skb)
+ * 	Description
+ * 		If the **struct sk_buff** pointed by *skb* has a known socket,
+ * 		retrieve the cookie (generated by the kernel) of this socket.
+ * 		If no cookie has been set yet, generate a new cookie. Once
+ * 		generated, the socket cookie remains stable for the life of the
+ * 		socket. This helper can be useful for monitoring per socket
+ * 		networking traffic statistics as it provides a unique socket
+ * 		identifier per namespace.
+ * 	Return
+ * 		A 8-byte long non-decreasing number on success, or 0 if the
+ * 		socket field is missing inside *skb*.
+ *
+ * u32 bpf_get_socket_uid(struct sk_buff *skb)
+ * 	Return
+ * 		The owner UID of the socket associated to *skb*. If the socket
+ * 		is **NULL**, or if it is not a full socket (i.e. if it is a
+ * 		time-wait or a request socket instead), **overflowuid** value
+ * 		is returned (note that **overflowuid** might also be the actual
+ * 		UID value for the socket).
+ *
+ * u32 bpf_set_hash(struct sk_buff *skb, u32 hash)
+ * 	Description
+ * 		Set the full hash for *skb* (set the field *skb*\ **->hash**)
+ * 		to value *hash*.
+ * 	Return
+ * 		0
+ *
+ * int bpf_setsockopt(struct bpf_sock_ops_kern *bpf_socket, int level, int optname, char *optval, int optlen)
+ * 	Description
+ * 		Emulate a call to **setsockopt()** on the socket associated to
+ * 		*bpf_socket*, which must be a full socket. The *level* at
+ * 		which the option resides and the name *optname* of the option
+ * 		must be specified, see **setsockopt(2)** for more information.
+ * 		The option value of length *optlen* is pointed by *optval*.
+ *
+ * 		This helper actually implements a subset of **setsockopt()**.
+ * 		It supports the following *level*\ s:
+ *
+ * 		* **SOL_SOCKET**, which supports the following *optname*\ s:
+ * 		  **SO_RCVBUF**, **SO_SNDBUF**, **SO_MAX_PACING_RATE**,
+ * 		  **SO_PRIORITY**, **SO_RCVLOWAT**, **SO_MARK**.
+ * 		* **IPPROTO_TCP**, which supports the following *optname*\ s:
+ * 		  **TCP_CONGESTION**, **TCP_BPF_IW**,
+ * 		  **TCP_BPF_SNDCWND_CLAMP**.
+ * 		* **IPPROTO_IP**, which supports *optname* **IP_TOS**.
+ * 		* **IPPROTO_IPV6**, which supports *optname* **IPV6_TCLASS**.
+ * 	Return
+ * 		0 on success, or a negative error in case of failure.
+ *
+ * int bpf_skb_adjust_room(struct sk_buff *skb, u32 len_diff, u32 mode, u64 flags)
+ * 	Description
+ * 		Grow or shrink the room for data in the packet associated to
+ * 		*skb* by *len_diff*, and according to the selected *mode*.
+ *
+ * 		There is a single supported mode at this time:
+ *
+ * 		* **BPF_ADJ_ROOM_NET**: Adjust room at the network layer
+ * 		  (room space is added or removed below the layer 3 header).
+ *
+ * 		All values for *flags* are reserved for future usage, and must
+ * 		be left at zero.
+ *
+ * 		A call to this helper is susceptible to change the underlaying
+ * 		packet buffer. Therefore, at load time, all checks on pointers
+ * 		previously done by the verifier are invalidated and must be
+ * 		performed again, if the helper is used in combination with
+ * 		direct packet access.
+ * 	Return
+ * 		0 on success, or a negative error in case of failure.
+ *
+ * int bpf_redirect_map(struct bpf_map *map, u32 key, u64 flags)
+ * 	Description
+ * 		Redirect the packet to the endpoint referenced by *map* at
+ * 		index *key*. Depending on its type, this *map* can contain
+ * 		references to net devices (for forwarding packets through other
+ * 		ports), or to CPUs (for redirecting XDP frames to another CPU;
+ * 		but this is only implemented for native XDP (with driver
+ * 		support) as of this writing).
+ *
+ * 		All values for *flags* are reserved for future usage, and must
+ * 		be left at zero.
+ *
+ * 		When used to redirect packets to net devices, this helper
+ * 		provides a high performance increase over **bpf_redirect**\ ().
+ * 		This is due to various implementation details of the underlying
+ * 		mechanisms, one of which is the fact that **bpf_redirect_map**\
+ * 		() tries to send packet as a "bulk" to the device.
+ * 	Return
+ * 		**XDP_REDIRECT** on success, or **XDP_ABORTED** on error.
+ *
+ * int bpf_sk_redirect_map(struct bpf_map *map, u32 key, u64 flags)
+ * 	Description
+ * 		Redirect the packet to the socket referenced by *map* (of type
+ * 		**BPF_MAP_TYPE_SOCKMAP**) at index *key*. Both ingress and
+ * 		egress interfaces can be used for redirection. The
+ * 		**BPF_F_INGRESS** value in *flags* is used to make the
+ * 		distinction (ingress path is selected if the flag is present,
+ * 		egress path otherwise). This is the only flag supported for now.
+ * 	Return
+ * 		**SK_PASS** on success, or **SK_DROP** on error.
+ *
+ * int bpf_sock_map_update(struct bpf_sock_ops_kern *skops, struct bpf_map *map, void *key, u64 flags)
+ * 	Description
+ * 		Add an entry to, or update a *map* referencing sockets. The
+ * 		*skops* is used as a new value for the entry associated to
+ * 		*key*. *flags* is one of:
+ *
+ * 		**BPF_NOEXIST**
+ * 			The entry for *key* must not exist in the map.
+ * 		**BPF_EXIST**
+ * 			The entry for *key* must already exist in the map.
+ * 		**BPF_ANY**
+ * 			No condition on the existence of the entry for *key*.
+ *
+ * 		If the *map* has eBPF programs (parser and verdict), those will
+ * 		be inherited by the socket being added. If the socket is
+ * 		already attached to eBPF programs, this results in an error.
+ * 	Return
+ * 		0 on success, or a negative error in case of failure.
+ *
+ * int bpf_xdp_adjust_meta(struct xdp_buff *xdp_md, int delta)
+ * 	Description
+ * 		Adjust the address pointed by *xdp_md*\ **->data_meta** by
+ * 		*delta* (which can be positive or negative). Note that this
+ * 		operation modifies the address stored in *xdp_md*\ **->data**,
+ * 		so the latter must be loaded only after the helper has been
+ * 		called.
+ *
+ * 		The use of *xdp_md*\ **->data_meta** is optional and programs
+ * 		are not required to use it. The rationale is that when the
+ * 		packet is processed with XDP (e.g. as DoS filter), it is
+ * 		possible to push further meta data along with it before passing
+ * 		to the stack, and to give the guarantee that an ingress eBPF
+ * 		program attached as a TC classifier on the same device can pick
+ * 		this up for further post-processing. Since TC works with socket
+ * 		buffers, it remains possible to set from XDP the **mark** or
+ * 		**priority** pointers, or other pointers for the socket buffer.
+ * 		Having this scratch space generic and programmable allows for
+ * 		more flexibility as the user is free to store whatever meta
+ * 		data they need.
+ *
+ * 		A call to this helper is susceptible to change the underlaying
+ * 		packet buffer. Therefore, at load time, all checks on pointers
+ * 		previously done by the verifier are invalidated and must be
+ * 		performed again, if the helper is used in combination with
+ * 		direct packet access.
+ * 	Return
+ * 		0 on success, or a negative error in case of failure.
+ *
+ * int bpf_perf_event_read_value(struct bpf_map *map, u64 flags, struct bpf_perf_event_value *buf, u32 buf_size)
+ * 	Description
+ * 		Read the value of a perf event counter, and store it into *buf*
+ * 		of size *buf_size*. This helper relies on a *map* of type
+ * 		**BPF_MAP_TYPE_PERF_EVENT_ARRAY**. The nature of the perf event
+ * 		counter is selected when *map* is updated with perf event file
+ * 		descriptors. The *map* is an array whose size is the number of
+ * 		available CPUs, and each cell contains a value relative to one
+ * 		CPU. The value to retrieve is indicated by *flags*, that
+ * 		contains the index of the CPU to look up, masked with
+ * 		**BPF_F_INDEX_MASK**. Alternatively, *flags* can be set to
+ * 		**BPF_F_CURRENT_CPU** to indicate that the value for the
+ * 		current CPU should be retrieved.
+ *
+ * 		This helper behaves in a way close to
+ * 		**bpf_perf_event_read**\ () helper, save that instead of
+ * 		just returning the value observed, it fills the *buf*
+ * 		structure. This allows for additional data to be retrieved: in
+ * 		particular, the enabled and running times (in *buf*\
+ * 		**->enabled** and *buf*\ **->running**, respectively) are
+ * 		copied. In general, **bpf_perf_event_read_value**\ () is
+ * 		recommended over **bpf_perf_event_read**\ (), which has some
+ * 		ABI issues and provides fewer functionalities.
+ *
+ * 		These values are interesting, because hardware PMU (Performance
+ * 		Monitoring Unit) counters are limited resources. When there are
+ * 		more PMU based perf events opened than available counters,
+ * 		kernel will multiplex these events so each event gets certain
+ * 		percentage (but not all) of the PMU time. In case that
+ * 		multiplexing happens, the number of samples or counter value
+ * 		will not reflect the case compared to when no multiplexing
+ * 		occurs. This makes comparison between different runs difficult.
+ * 		Typically, the counter value should be normalized before
+ * 		comparing to other experiments. The usual normalization is done
+ * 		as follows.
+ *
+ * 		::
+ *
+ * 			normalized_counter = counter * t_enabled / t_running
+ *
+ * 		Where t_enabled is the time enabled for event and t_running is
+ * 		the time running for event since last normalization. The
+ * 		enabled and running times are accumulated since the perf event
+ * 		open. To achieve scaling factor between two invocations of an
+ * 		eBPF program, users can can use CPU id as the key (which is
+ * 		typical for perf array usage model) to remember the previous
+ * 		value and do the calculation inside the eBPF program.
+ * 	Return
+ * 		0 on success, or a negative error in case of failure.
+ *
+ * int bpf_perf_prog_read_value(struct bpf_perf_event_data_kern *ctx, struct bpf_perf_event_value *buf, u32 buf_size)
+ * 	Description
+ * 		For en eBPF program attached to a perf event, retrieve the
+ * 		value of the event counter associated to *ctx* and store it in
+ * 		the structure pointed by *buf* and of size *buf_size*. Enabled
+ * 		and running times are also stored in the structure (see
+ * 		description of helper **bpf_perf_event_read_value**\ () for
+ * 		more details).
+ * 	Return
+ * 		0 on success, or a negative error in case of failure.
+ *
+ * int bpf_getsockopt(struct bpf_sock_ops_kern *bpf_socket, int level, int optname, char *optval, int optlen)
+ * 	Description
+ * 		Emulate a call to **getsockopt()** on the socket associated to
+ * 		*bpf_socket*, which must be a full socket. The *level* at
+ * 		which the option resides and the name *optname* of the option
+ * 		must be specified, see **getsockopt(2)** for more information.
+ * 		The retrieved value is stored in the structure pointed by
+ * 		*opval* and of length *optlen*.
+ *
+ * 		This helper actually implements a subset of **getsockopt()**.
+ * 		It supports the following *level*\ s:
+ *
+ * 		* **IPPROTO_TCP**, which supports *optname*
+ * 		  **TCP_CONGESTION**.
+ * 		* **IPPROTO_IP**, which supports *optname* **IP_TOS**.
+ * 		* **IPPROTO_IPV6**, which supports *optname* **IPV6_TCLASS**.
+ * 	Return
+ * 		0 on success, or a negative error in case of failure.
+ *
+ * int bpf_override_return(struct pt_reg *regs, u64 rc)
+ * 	Description
+ * 		Used for error injection, this helper uses kprobes to override
+ * 		the return value of the probed function, and to set it to *rc*.
+ * 		The first argument is the context *regs* on which the kprobe
+ * 		works.
+ *
+ * 		This helper works by setting setting the PC (program counter)
+ * 		to an override function which is run in place of the original
+ * 		probed function. This means the probed function is not run at
+ * 		all. The replacement function just returns with the required
+ * 		value.
+ *
+ * 		This helper has security implications, and thus is subject to
+ * 		restrictions. It is only available if the kernel was compiled
+ * 		with the **CONFIG_BPF_KPROBE_OVERRIDE** configuration
+ * 		option, and in this case it only works on functions tagged with
+ * 		**ALLOW_ERROR_INJECTION** in the kernel code.
+ *
+ * 		Also, the helper is only available for the architectures having
+ * 		the CONFIG_FUNCTION_ERROR_INJECTION option. As of this writing,
+ * 		x86 architecture is the only one to support this feature.
+ * 	Return
+ * 		0
+ *
+ * int bpf_sock_ops_cb_flags_set(struct bpf_sock_ops_kern *bpf_sock, int argval)
+ * 	Description
+ * 		Attempt to set the value of the **bpf_sock_ops_cb_flags** field
+ * 		for the full TCP socket associated to *bpf_sock_ops* to
+ * 		*argval*.
+ *
+ * 		The primary use of this field is to determine if there should
+ * 		be calls to eBPF programs of type
+ * 		**BPF_PROG_TYPE_SOCK_OPS** at various points in the TCP
+ * 		code. A program of the same type can change its value, per
+ * 		connection and as necessary, when the connection is
+ * 		established. This field is directly accessible for reading, but
+ * 		this helper must be used for updates in order to return an
+ * 		error if an eBPF program tries to set a callback that is not
+ * 		supported in the current kernel.
+ *
+ * 		The supported callback values that *argval* can combine are:
+ *
+ * 		* **BPF_SOCK_OPS_RTO_CB_FLAG** (retransmission time out)
+ * 		* **BPF_SOCK_OPS_RETRANS_CB_FLAG** (retransmission)
+ * 		* **BPF_SOCK_OPS_STATE_CB_FLAG** (TCP state change)
+ *
+ * 		Here are some examples of where one could call such eBPF
+ * 		program:
+ *
+ * 		* When RTO fires.
+ * 		* When a packet is retransmitted.
+ * 		* When the connection terminates.
+ * 		* When a packet is sent.
+ * 		* When a packet is received.
+ * 	Return
+ * 		Code **-EINVAL** if the socket is not a full TCP socket;
+ * 		otherwise, a positive number containing the bits that could not
+ * 		be set is returned (which comes down to 0 if all bits were set
+ * 		as required).
+ *
+ * int bpf_msg_redirect_map(struct sk_msg_buff *msg, struct bpf_map *map, u32 key, u64 flags)
+ * 	Description
+ * 		This helper is used in programs implementing policies at the
+ * 		socket level. If the message *msg* is allowed to pass (i.e. if
+ * 		the verdict eBPF program returns **SK_PASS**), redirect it to
+ * 		the socket referenced by *map* (of type
+ * 		**BPF_MAP_TYPE_SOCKMAP**) at index *key*. Both ingress and
+ * 		egress interfaces can be used for redirection. The
+ * 		**BPF_F_INGRESS** value in *flags* is used to make the
+ * 		distinction (ingress path is selected if the flag is present,
+ * 		egress path otherwise). This is the only flag supported for now.
+ * 	Return
+ * 		**SK_PASS** on success, or **SK_DROP** on error.
+ *
+ * int bpf_msg_apply_bytes(struct sk_msg_buff *msg, u32 bytes)
+ * 	Description
+ * 		For socket policies, apply the verdict of the eBPF program to
+ * 		the next *bytes* (number of bytes) of message *msg*.
+ *
+ * 		For example, this helper can be used in the following cases:
+ *
+ * 		* A single **sendmsg**\ () or **sendfile**\ () system call
+ * 		  contains multiple logical messages that the eBPF program is
+ * 		  supposed to read and for which it should apply a verdict.
+ * 		* An eBPF program only cares to read the first *bytes* of a
+ * 		  *msg*. If the message has a large payload, then setting up
+ * 		  and calling the eBPF program repeatedly for all bytes, even
+ * 		  though the verdict is already known, would create unnecessary
+ * 		  overhead.
+ *
+ * 		When called from within an eBPF program, the helper sets a
+ * 		counter internal to the BPF infrastructure, that is used to
+ * 		apply the last verdict to the next *bytes*. If *bytes* is
+ * 		smaller than the current data being processed from a
+ * 		**sendmsg**\ () or **sendfile**\ () system call, the first
+ * 		*bytes* will be sent and the eBPF program will be re-run with
+ * 		the pointer for start of data pointing to byte number *bytes*
+ * 		**+ 1**. If *bytes* is larger than the current data being
+ * 		processed, then the eBPF verdict will be applied to multiple
+ * 		**sendmsg**\ () or **sendfile**\ () calls until *bytes* are
+ * 		consumed.
+ *
+ * 		Note that if a socket closes with the internal counter holding
+ * 		a non-zero value, this is not a problem because data is not
+ * 		being buffered for *bytes* and is sent as it is received.
+ * 	Return
+ * 		0
+ *
+ * int bpf_msg_cork_bytes(struct sk_msg_buff *msg, u32 bytes)
+ * 	Description
+ * 		For socket policies, prevent the execution of the verdict eBPF
+ * 		program for message *msg* until *bytes* (byte number) have been
+ * 		accumulated.
+ *
+ * 		This can be used when one needs a specific number of bytes
+ * 		before a verdict can be assigned, even if the data spans
+ * 		multiple **sendmsg**\ () or **sendfile**\ () calls. The extreme
+ * 		case would be a user calling **sendmsg**\ () repeatedly with
+ * 		1-byte long message segments. Obviously, this is bad for
+ * 		performance, but it is still valid. If the eBPF program needs
+ * 		*bytes* bytes to validate a header, this helper can be used to
+ * 		prevent the eBPF program to be called again until *bytes* have
+ * 		been accumulated.
+ * 	Return
+ * 		0
+ *
+ * int bpf_msg_pull_data(struct sk_msg_buff *msg, u32 start, u32 end, u64 flags)
+ * 	Description
+ * 		For socket policies, pull in non-linear data from user space
+ * 		for *msg* and set pointers *msg*\ **->data** and *msg*\
+ * 		**->data_end** to *start* and *end* bytes offsets into *msg*,
+ * 		respectively.
+ *
+ * 		If a program of type **BPF_PROG_TYPE_SK_MSG** is run on a
+ * 		*msg* it can only parse data that the (**data**, **data_end**)
+ * 		pointers have already consumed. For **sendmsg**\ () hooks this
+ * 		is likely the first scatterlist element. But for calls relying
+ * 		on the **sendpage** handler (e.g. **sendfile**\ ()) this will
+ * 		be the range (**0**, **0**) because the data is shared with
+ * 		user space and by default the objective is to avoid allowing
+ * 		user space to modify data while (or after) eBPF verdict is
+ * 		being decided. This helper can be used to pull in data and to
+ * 		set the start and end pointer to given values. Data will be
+ * 		copied if necessary (i.e. if data was not linear and if start
+ * 		and end pointers do not point to the same chunk).
+ *
+ * 		A call to this helper is susceptible to change the underlaying
+ * 		packet buffer. Therefore, at load time, all checks on pointers
+ * 		previously done by the verifier are invalidated and must be
+ * 		performed again, if the helper is used in combination with
+ * 		direct packet access.
+ *
+ * 		All values for *flags* are reserved for future usage, and must
+ * 		be left at zero.
+ * 	Return
+ * 		0 on success, or a negative error in case of failure.
+ *
+ * int bpf_bind(struct bpf_sock_addr_kern *ctx, struct sockaddr *addr, int addr_len)
+ * 	Description
+ * 		Bind the socket associated to *ctx* to the address pointed by
+ * 		*addr*, of length *addr_len*. This allows for making outgoing
+ * 		connection from the desired IP address, which can be useful for
+ * 		example when all processes inside a cgroup should use one
+ * 		single IP address on a host that has multiple IP configured.
+ *
+ * 		This helper works for IPv4 and IPv6, TCP and UDP sockets. The
+ * 		domain (*addr*\ **->sa_family**) must be **AF_INET** (or
+ * 		**AF_INET6**). Looking for a free port to bind to can be
+ * 		expensive, therefore binding to port is not permitted by the
+ * 		helper: *addr*\ **->sin_port** (or **sin6_port**, respectively)
+ * 		must be set to zero.
+ * 	Return
+ * 		0 on success, or a negative error in case of failure.
+ *
+ * int bpf_xdp_adjust_tail(struct xdp_buff *xdp_md, int delta)
+ * 	Description
+ * 		Adjust (move) *xdp_md*\ **->data_end** by *delta* bytes. It is
+ * 		only possible to shrink the packet as of this writing,
+ * 		therefore *delta* must be a negative integer.
+ *
+ * 		A call to this helper is susceptible to change the underlaying
+ * 		packet buffer. Therefore, at load time, all checks on pointers
+ * 		previously done by the verifier are invalidated and must be
+ * 		performed again, if the helper is used in combination with
+ * 		direct packet access.
+ * 	Return
+ * 		0 on success, or a negative error in case of failure.
+ *
+ * int bpf_skb_get_xfrm_state(struct sk_buff *skb, u32 index, struct bpf_xfrm_state *xfrm_state, u32 size, u64 flags)
+ * 	Description
+ * 		Retrieve the XFRM state (IP transform framework, see also
+ * 		**ip-xfrm(8)**) at *index* in XFRM "security path" for *skb*.
+ *
+ * 		The retrieved value is stored in the **struct bpf_xfrm_state**
+ * 		pointed by *xfrm_state* and of length *size*.
+ *
+ * 		All values for *flags* are reserved for future usage, and must
+ * 		be left at zero.
+ *
+ * 		This helper is available only if the kernel was compiled with
+ * 		**CONFIG_XFRM** configuration option.
+ * 	Return
+ * 		0 on success, or a negative error in case of failure.
  */
 #define __BPF_FUNC_MAPPER(FN)		\
 	FN(unspec),			\
@@ -841,7 +1834,8 @@ union bpf_attr {
 	FN(msg_cork_bytes),		\
 	FN(msg_pull_data),		\
 	FN(bind),			\
-	FN(xdp_adjust_tail),
+	FN(xdp_adjust_tail),		\
+	FN(skb_get_xfrm_state),
 
 /* integer value in 'imm' field of BPF_CALL instruction selects which helper
  * function eBPF program intends to call
@@ -947,6 +1941,19 @@ struct bpf_tunnel_key {
 	__u32 tunnel_label;
 };
 
+/* user accessible mirror of in-kernel xfrm_state.
+ * new fields can only be added to the end of this structure
+ */
+struct bpf_xfrm_state {
+	__u32 reqid;
+	__u32 spi;	/* Stored in network byte order */
+	__u16 family;
+	union {
+		__u32 remote_ipv4;	/* Stored in network byte order */
+		__u32 remote_ipv6[4];	/* Stored in network byte order */
+	};
+};
+
 /* Generic BPF return codes which all BPF program types may support.
  * The values are binary compatible with their TC_ACT_* counter-part to
  * provide backwards compatibility with existing SCHED_CLS and SCHED_ACT
@@ -1037,6 +2044,7 @@ struct bpf_prog_info {
 	__aligned_u64 map_ids;
 	char name[BPF_OBJ_NAME_LEN];
 	__u32 ifindex;
+	__u32 gpl_compatible:1;
 	__u64 netns_dev;
 	__u64 netns_ino;
 } __attribute__((aligned(8)));
diff --git a/include/uapi/linux/btf.h b/include/uapi/linux/btf.h
index 74a30b1090df..bcb56ee47014 100644
--- a/include/uapi/linux/btf.h
+++ b/include/uapi/linux/btf.h
@@ -6,9 +6,7 @@
 #include <linux/types.h>
 
 #define BTF_MAGIC	0xeB9F
-#define BTF_MAGIC_SWAP	0x9FeB
 #define BTF_VERSION	1
-#define BTF_FLAGS_COMPR	0x01
 
 struct btf_header {
 	__u16	magic;
@@ -43,7 +41,7 @@ struct btf_header {
 #define BTF_STR_OFFSET(ref)	((ref) & BTF_MAX_NAME_OFFSET)
 
 struct btf_type {
-	__u32 name;
+	__u32 name_off;
 	/* "info" bits arrangement
 	 * bits  0-15: vlen (e.g. # of struct's members)
 	 * bits 16-23: unused
@@ -105,7 +103,7 @@ struct btf_type {
  * info in "struct btf_type").
  */
 struct btf_enum {
-	__u32	name;
+	__u32	name_off;
 	__s32	val;
 };
 
@@ -122,7 +120,7 @@ struct btf_array {
  * "struct btf_type").
  */
 struct btf_member {
-	__u32	name;
+	__u32	name_off;
 	__u32	type;
 	__u32	offset;	/* offset in bits */
 };
diff --git a/kernel/bpf/btf.c b/kernel/bpf/btf.c
index eb56ac760547..22e1046a1a86 100644
--- a/kernel/bpf/btf.c
+++ b/kernel/bpf/btf.c
@@ -473,7 +473,7 @@ __printf(4, 5) static void __btf_verifier_log_type(struct btf_verifier_env *env,
 	__btf_verifier_log(log, "[%u] %s %s%s",
 			   env->log_type_id,
 			   btf_kind_str[kind],
-			   btf_name_by_offset(btf, t->name),
+			   btf_name_by_offset(btf, t->name_off),
 			   log_details ? " " : "");
 
 	if (log_details)
@@ -517,7 +517,7 @@ static void btf_verifier_log_member(struct btf_verifier_env *env,
 		btf_verifier_log_type(env, struct_type, NULL);
 
 	__btf_verifier_log(log, "\t%s type_id=%u bits_offset=%u",
-			   btf_name_by_offset(btf, member->name),
+			   btf_name_by_offset(btf, member->name_off),
 			   member->type, member->offset);
 
 	if (fmt && *fmt) {
@@ -1419,10 +1419,10 @@ static s32 btf_struct_check_meta(struct btf_verifier_env *env,
 	btf_verifier_log_type(env, t, NULL);
 
 	for_each_member(i, t, member) {
-		if (!btf_name_offset_valid(btf, member->name)) {
+		if (!btf_name_offset_valid(btf, member->name_off)) {
 			btf_verifier_log_member(env, t, member,
 						"Invalid member name_offset:%u",
-						member->name);
+						member->name_off);
 			return -EINVAL;
 		}
 
@@ -1605,14 +1605,14 @@ static s32 btf_enum_check_meta(struct btf_verifier_env *env,
 	btf_verifier_log_type(env, t, NULL);
 
 	for (i = 0; i < nr_enums; i++) {
-		if (!btf_name_offset_valid(btf, enums[i].name)) {
+		if (!btf_name_offset_valid(btf, enums[i].name_off)) {
 			btf_verifier_log(env, "\tInvalid name_offset:%u",
-					 enums[i].name);
+					 enums[i].name_off);
 			return -EINVAL;
 		}
 
 		btf_verifier_log(env, "\t%s val=%d\n",
-				 btf_name_by_offset(btf, enums[i].name),
+				 btf_name_by_offset(btf, enums[i].name_off),
 				 enums[i].val);
 	}
 
@@ -1636,7 +1636,7 @@ static void btf_enum_seq_show(const struct btf *btf, const struct btf_type *t,
 	for (i = 0; i < nr_enums; i++) {
 		if (v == enums[i].val) {
 			seq_printf(m, "%s",
-				   btf_name_by_offset(btf, enums[i].name));
+				   btf_name_by_offset(btf, enums[i].name_off));
 			return;
 		}
 	}
@@ -1687,9 +1687,9 @@ static s32 btf_check_meta(struct btf_verifier_env *env,
 		return -EINVAL;
 	}
 
-	if (!btf_name_offset_valid(env->btf, t->name)) {
+	if (!btf_name_offset_valid(env->btf, t->name_off)) {
 		btf_verifier_log(env, "[%u] Invalid name_offset:%u",
-				 env->log_type_id, t->name);
+				 env->log_type_id, t->name_off);
 		return -EINVAL;
 	}
 
diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c
index a22c26e6d58b..0bd2944eafb9 100644
--- a/kernel/bpf/syscall.c
+++ b/kernel/bpf/syscall.c
@@ -1914,6 +1914,7 @@ static int bpf_prog_get_info_by_fd(struct bpf_prog *prog,
 	info.load_time = prog->aux->load_time;
 	info.created_by_uid = from_kuid_munged(current_user_ns(),
 					       prog->aux->user->uid);
+	info.gpl_compatible = prog->gpl_compatible;
 
 	memcpy(info.tag, prog->tag, sizeof(prog->tag));
 	memcpy(info.name, prog->aux->name, sizeof(prog->aux->name));
diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
index 5dd1dcb902bf..eb1a596aebd3 100644
--- a/kernel/bpf/verifier.c
+++ b/kernel/bpf/verifier.c
@@ -1914,7 +1914,7 @@ static int check_func_arg(struct bpf_verifier_env *env, u32 regno,
 	if (arg_type == ARG_PTR_TO_MAP_KEY ||
 	    arg_type == ARG_PTR_TO_MAP_VALUE) {
 		expected_type = PTR_TO_STACK;
-		if (!type_is_pkt_pointer(type) &&
+		if (!type_is_pkt_pointer(type) && type != PTR_TO_MAP_VALUE &&
 		    type != expected_type)
 			goto err_type;
 	} else if (arg_type == ARG_CONST_SIZE ||
@@ -1966,14 +1966,9 @@ static int check_func_arg(struct bpf_verifier_env *env, u32 regno,
 			verbose(env, "invalid map_ptr to access map->key\n");
 			return -EACCES;
 		}
-		if (type_is_pkt_pointer(type))
-			err = check_packet_access(env, regno, reg->off,
-						  meta->map_ptr->key_size,
-						  false);
-		else
-			err = check_stack_boundary(env, regno,
-						   meta->map_ptr->key_size,
-						   false, NULL);
+		err = check_helper_mem_access(env, regno,
+					      meta->map_ptr->key_size, false,
+					      NULL);
 	} else if (arg_type == ARG_PTR_TO_MAP_VALUE) {
 		/* bpf_map_xxx(..., map_ptr, ..., value) call:
 		 * check [value, value + map->value_size) validity
@@ -1983,14 +1978,9 @@ static int check_func_arg(struct bpf_verifier_env *env, u32 regno,
 			verbose(env, "invalid map_ptr to access map->value\n");
 			return -EACCES;
 		}
-		if (type_is_pkt_pointer(type))
-			err = check_packet_access(env, regno, reg->off,
-						  meta->map_ptr->value_size,
-						  false);
-		else
-			err = check_stack_boundary(env, regno,
-						   meta->map_ptr->value_size,
-						   false, NULL);
+		err = check_helper_mem_access(env, regno,
+					      meta->map_ptr->value_size, false,
+					      NULL);
 	} else if (arg_type_is_mem_size(arg_type)) {
 		bool zero_size_allowed = (arg_type == ARG_CONST_SIZE_OR_ZERO);
 
diff --git a/net/core/dev.c b/net/core/dev.c
index c624a04dad1f..8f8931b93140 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -4057,8 +4057,10 @@ static u32 netif_receive_generic_xdp(struct sk_buff *skb,
 	 * pckt.
 	 */
 	off = orig_data_end - xdp.data_end;
-	if (off != 0)
+	if (off != 0) {
 		skb_set_tail_pointer(skb, xdp.data_end - xdp.data);
+		skb->len -= off;
+	}
 
 	switch (act) {
 	case XDP_REDIRECT:
diff --git a/net/core/filter.c b/net/core/filter.c
index a2d093c581f1..d3781daa26ab 100644
--- a/net/core/filter.c
+++ b/net/core/filter.c
@@ -57,6 +57,7 @@
 #include <net/sock_reuseport.h>
 #include <net/busy_poll.h>
 #include <net/tcp.h>
+#include <net/xfrm.h>
 #include <linux/bpf_trace.h>
 
 /**
@@ -3744,6 +3745,49 @@ static const struct bpf_func_proto bpf_bind_proto = {
 	.arg3_type	= ARG_CONST_SIZE,
 };
 
+#ifdef CONFIG_XFRM
+BPF_CALL_5(bpf_skb_get_xfrm_state, struct sk_buff *, skb, u32, index,
+	   struct bpf_xfrm_state *, to, u32, size, u64, flags)
+{
+	const struct sec_path *sp = skb_sec_path(skb);
+	const struct xfrm_state *x;
+
+	if (!sp || unlikely(index >= sp->len || flags))
+		goto err_clear;
+
+	x = sp->xvec[index];
+
+	if (unlikely(size != sizeof(struct bpf_xfrm_state)))
+		goto err_clear;
+
+	to->reqid = x->props.reqid;
+	to->spi = x->id.spi;
+	to->family = x->props.family;
+	if (to->family == AF_INET6) {
+		memcpy(to->remote_ipv6, x->props.saddr.a6,
+		       sizeof(to->remote_ipv6));
+	} else {
+		to->remote_ipv4 = x->props.saddr.a4;
+	}
+
+	return 0;
+err_clear:
+	memset(to, 0, size);
+	return -EINVAL;
+}
+
+static const struct bpf_func_proto bpf_skb_get_xfrm_state_proto = {
+	.func		= bpf_skb_get_xfrm_state,
+	.gpl_only	= false,
+	.ret_type	= RET_INTEGER,
+	.arg1_type	= ARG_PTR_TO_CTX,
+	.arg2_type	= ARG_ANYTHING,
+	.arg3_type	= ARG_PTR_TO_UNINIT_MEM,
+	.arg4_type	= ARG_CONST_SIZE,
+	.arg5_type	= ARG_ANYTHING,
+};
+#endif
+
 static const struct bpf_func_proto *
 bpf_base_func_proto(enum bpf_func_id func_id)
 {
@@ -3885,6 +3929,10 @@ tc_cls_act_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
 		return &bpf_get_socket_cookie_proto;
 	case BPF_FUNC_get_socket_uid:
 		return &bpf_get_socket_uid_proto;
+#ifdef CONFIG_XFRM
+	case BPF_FUNC_skb_get_xfrm_state:
+		return &bpf_skb_get_xfrm_state_proto;
+#endif
 	default:
 		return bpf_base_func_proto(func_id);
 	}
diff --git a/samples/bpf/Makefile b/samples/bpf/Makefile
index aa8c392e2e52..b853581592fd 100644
--- a/samples/bpf/Makefile
+++ b/samples/bpf/Makefile
@@ -114,7 +114,6 @@ always += sock_flags_kern.o
 always += test_probe_write_user_kern.o
 always += trace_output_kern.o
 always += tcbpf1_kern.o
-always += tcbpf2_kern.o
 always += tc_l2_redirect_kern.o
 always += lathist_kern.o
 always += offwaketime_kern.o
diff --git a/samples/bpf/bpf_load.c b/samples/bpf/bpf_load.c
index bebe4188b4b3..feca497d6afd 100644
--- a/samples/bpf/bpf_load.c
+++ b/samples/bpf/bpf_load.c
@@ -549,7 +549,6 @@ static int do_load_bpf_file(const char *path, fixup_map_cb fixup_map)
 		if (nr_maps < 0) {
 			printf("Error: Failed loading ELF maps (errno:%d):%s\n",
 			       nr_maps, strerror(-nr_maps));
-			ret = 1;
 			goto done;
 		}
 		if (load_maps(map_data, nr_maps, fixup_map))
@@ -615,7 +614,6 @@ static int do_load_bpf_file(const char *path, fixup_map_cb fixup_map)
 		}
 	}
 
-	ret = 0;
 done:
 	close(fd);
 	return ret;
diff --git a/samples/bpf/test_tunnel_bpf.sh b/samples/bpf/test_tunnel_bpf.sh
deleted file mode 100755
index c265863ccdf9..000000000000
--- a/samples/bpf/test_tunnel_bpf.sh
+++ /dev/null
@@ -1,319 +0,0 @@
-#!/bin/bash
-# SPDX-License-Identifier: GPL-2.0
-# In Namespace 0 (at_ns0) using native tunnel
-# Overlay IP: 10.1.1.100
-# local 192.16.1.100 remote 192.16.1.200
-# veth0 IP: 172.16.1.100, tunnel dev <type>00
-
-# Out of Namespace using BPF set/get on lwtunnel
-# Overlay IP: 10.1.1.200
-# local 172.16.1.200 remote 172.16.1.100
-# veth1 IP: 172.16.1.200, tunnel dev <type>11
-
-function config_device {
-	ip netns add at_ns0
-	ip link add veth0 type veth peer name veth1
-	ip link set veth0 netns at_ns0
-	ip netns exec at_ns0 ip addr add 172.16.1.100/24 dev veth0
-	ip netns exec at_ns0 ip link set dev veth0 up
-	ip link set dev veth1 up mtu 1500
-	ip addr add dev veth1 172.16.1.200/24
-}
-
-function add_gre_tunnel {
-	# in namespace
-	ip netns exec at_ns0 \
-        ip link add dev $DEV_NS type $TYPE seq key 2 \
-		local 172.16.1.100 remote 172.16.1.200
-	ip netns exec at_ns0 ip link set dev $DEV_NS up
-	ip netns exec at_ns0 ip addr add dev $DEV_NS 10.1.1.100/24
-
-	# out of namespace
-	ip link add dev $DEV type $TYPE key 2 external
-	ip link set dev $DEV up
-	ip addr add dev $DEV 10.1.1.200/24
-}
-
-function add_ip6gretap_tunnel {
-
-	# assign ipv6 address
-	ip netns exec at_ns0 ip addr add ::11/96 dev veth0
-	ip netns exec at_ns0 ip link set dev veth0 up
-	ip addr add dev veth1 ::22/96
-	ip link set dev veth1 up
-
-	# in namespace
-	ip netns exec at_ns0 \
-		ip link add dev $DEV_NS type $TYPE seq flowlabel 0xbcdef key 2 \
-		local ::11 remote ::22
-
-	ip netns exec at_ns0 ip addr add dev $DEV_NS 10.1.1.100/24
-	ip netns exec at_ns0 ip addr add dev $DEV_NS fc80::100/96
-	ip netns exec at_ns0 ip link set dev $DEV_NS up
-
-	# out of namespace
-	ip link add dev $DEV type $TYPE external
-	ip addr add dev $DEV 10.1.1.200/24
-	ip addr add dev $DEV fc80::200/24
-	ip link set dev $DEV up
-}
-
-function add_erspan_tunnel {
-	# in namespace
-	if [ "$1" == "v1" ]; then
-		ip netns exec at_ns0 \
-		ip link add dev $DEV_NS type $TYPE seq key 2 \
-		local 172.16.1.100 remote 172.16.1.200 \
-		erspan_ver 1 erspan 123
-	else
-		ip netns exec at_ns0 \
-		ip link add dev $DEV_NS type $TYPE seq key 2 \
-		local 172.16.1.100 remote 172.16.1.200 \
-		erspan_ver 2 erspan_dir egress erspan_hwid 3
-	fi
-	ip netns exec at_ns0 ip link set dev $DEV_NS up
-	ip netns exec at_ns0 ip addr add dev $DEV_NS 10.1.1.100/24
-
-	# out of namespace
-	ip link add dev $DEV type $TYPE external
-	ip link set dev $DEV up
-	ip addr add dev $DEV 10.1.1.200/24
-}
-
-function add_ip6erspan_tunnel {
-
-	# assign ipv6 address
-	ip netns exec at_ns0 ip addr add ::11/96 dev veth0
-	ip netns exec at_ns0 ip link set dev veth0 up
-	ip addr add dev veth1 ::22/96
-	ip link set dev veth1 up
-
-	# in namespace
-	if [ "$1" == "v1" ]; then
-		ip netns exec at_ns0 \
-		ip link add dev $DEV_NS type $TYPE seq key 2 \
-		local ::11 remote ::22 \
-		erspan_ver 1 erspan 123
-	else
-		ip netns exec at_ns0 \
-		ip link add dev $DEV_NS type $TYPE seq key 2 \
-		local ::11 remote ::22 \
-		erspan_ver 2 erspan_dir egress erspan_hwid 7
-	fi
-	ip netns exec at_ns0 ip addr add dev $DEV_NS 10.1.1.100/24
-	ip netns exec at_ns0 ip link set dev $DEV_NS up
-
-	# out of namespace
-	ip link add dev $DEV type $TYPE external
-	ip addr add dev $DEV 10.1.1.200/24
-	ip link set dev $DEV up
-}
-
-function add_vxlan_tunnel {
-	# Set static ARP entry here because iptables set-mark works
-	# on L3 packet, as a result not applying to ARP packets,
-	# causing errors at get_tunnel_{key/opt}.
-
-	# in namespace
-	ip netns exec at_ns0 \
-		ip link add dev $DEV_NS type $TYPE id 2 dstport 4789 gbp remote 172.16.1.200
-	ip netns exec at_ns0 ip link set dev $DEV_NS address 52:54:00:d9:01:00 up
-	ip netns exec at_ns0 ip addr add dev $DEV_NS 10.1.1.100/24
-	ip netns exec at_ns0 arp -s 10.1.1.200 52:54:00:d9:02:00
-	ip netns exec at_ns0 iptables -A OUTPUT -j MARK --set-mark 0x800FF
-
-	# out of namespace
-	ip link add dev $DEV type $TYPE external gbp dstport 4789
-	ip link set dev $DEV address 52:54:00:d9:02:00 up
-	ip addr add dev $DEV 10.1.1.200/24
-	arp -s 10.1.1.100 52:54:00:d9:01:00
-}
-
-function add_geneve_tunnel {
-	# in namespace
-	ip netns exec at_ns0 \
-		ip link add dev $DEV_NS type $TYPE id 2 dstport 6081 remote 172.16.1.200
-	ip netns exec at_ns0 ip link set dev $DEV_NS up
-	ip netns exec at_ns0 ip addr add dev $DEV_NS 10.1.1.100/24
-
-	# out of namespace
-	ip link add dev $DEV type $TYPE dstport 6081 external
-	ip link set dev $DEV up
-	ip addr add dev $DEV 10.1.1.200/24
-}
-
-function add_ipip_tunnel {
-	# in namespace
-	ip netns exec at_ns0 \
-		ip link add dev $DEV_NS type $TYPE local 172.16.1.100 remote 172.16.1.200
-	ip netns exec at_ns0 ip link set dev $DEV_NS up
-	ip netns exec at_ns0 ip addr add dev $DEV_NS 10.1.1.100/24
-
-	# out of namespace
-	ip link add dev $DEV type $TYPE external
-	ip link set dev $DEV up
-	ip addr add dev $DEV 10.1.1.200/24
-}
-
-function attach_bpf {
-	DEV=$1
-	SET_TUNNEL=$2
-	GET_TUNNEL=$3
-	tc qdisc add dev $DEV clsact
-	tc filter add dev $DEV egress bpf da obj tcbpf2_kern.o sec $SET_TUNNEL
-	tc filter add dev $DEV ingress bpf da obj tcbpf2_kern.o sec $GET_TUNNEL
-}
-
-function test_gre {
-	TYPE=gretap
-	DEV_NS=gretap00
-	DEV=gretap11
-	config_device
-	add_gre_tunnel
-	attach_bpf $DEV gre_set_tunnel gre_get_tunnel
-	ping -c 1 10.1.1.100
-	ip netns exec at_ns0 ping -c 1 10.1.1.200
-	cleanup
-}
-
-function test_ip6gre {
-	TYPE=ip6gre
-	DEV_NS=ip6gre00
-	DEV=ip6gre11
-	config_device
-	# reuse the ip6gretap function
-	add_ip6gretap_tunnel
-	attach_bpf $DEV ip6gretap_set_tunnel ip6gretap_get_tunnel
-	# underlay
-	ping6 -c 4 ::11
-	# overlay: ipv4 over ipv6
-	ip netns exec at_ns0 ping -c 1 10.1.1.200
-	ping -c 1 10.1.1.100
-	# overlay: ipv6 over ipv6
-	ip netns exec at_ns0 ping6 -c 1 fc80::200
-	cleanup
-}
-
-function test_ip6gretap {
-	TYPE=ip6gretap
-	DEV_NS=ip6gretap00
-	DEV=ip6gretap11
-	config_device
-	add_ip6gretap_tunnel
-	attach_bpf $DEV ip6gretap_set_tunnel ip6gretap_get_tunnel
-	# underlay
-	ping6 -c 4 ::11
-	# overlay: ipv4 over ipv6
-	ip netns exec at_ns0 ping -i .2 -c 1 10.1.1.200
-	ping -c 1 10.1.1.100
-	# overlay: ipv6 over ipv6
-	ip netns exec at_ns0 ping6 -c 1 fc80::200
-	cleanup
-}
-
-function test_erspan {
-	TYPE=erspan
-	DEV_NS=erspan00
-	DEV=erspan11
-	config_device
-	add_erspan_tunnel $1
-	attach_bpf $DEV erspan_set_tunnel erspan_get_tunnel
-	ping -c 1 10.1.1.100
-	ip netns exec at_ns0 ping -c 1 10.1.1.200
-	cleanup
-}
-
-function test_ip6erspan {
-	TYPE=ip6erspan
-	DEV_NS=ip6erspan00
-	DEV=ip6erspan11
-	config_device
-	add_ip6erspan_tunnel $1
-	attach_bpf $DEV ip4ip6erspan_set_tunnel ip4ip6erspan_get_tunnel
-	ping6 -c 3 ::11
-	ip netns exec at_ns0 ping -c 1 10.1.1.200
-	cleanup
-}
-
-function test_vxlan {
-	TYPE=vxlan
-	DEV_NS=vxlan00
-	DEV=vxlan11
-	config_device
-	add_vxlan_tunnel
-	attach_bpf $DEV vxlan_set_tunnel vxlan_get_tunnel
-	ping -c 1 10.1.1.100
-	ip netns exec at_ns0 ping -c 1 10.1.1.200
-	cleanup
-}
-
-function test_geneve {
-	TYPE=geneve
-	DEV_NS=geneve00
-	DEV=geneve11
-	config_device
-	add_geneve_tunnel
-	attach_bpf $DEV geneve_set_tunnel geneve_get_tunnel
-	ping -c 1 10.1.1.100
-	ip netns exec at_ns0 ping -c 1 10.1.1.200
-	cleanup
-}
-
-function test_ipip {
-	TYPE=ipip
-	DEV_NS=ipip00
-	DEV=ipip11
-	config_device
-	tcpdump -nei veth1 &
-	cat /sys/kernel/debug/tracing/trace_pipe &
-	add_ipip_tunnel
-	ethtool -K veth1 gso off gro off rx off tx off
-	ip link set dev veth1 mtu 1500
-	attach_bpf $DEV ipip_set_tunnel ipip_get_tunnel
-	ping -c 1 10.1.1.100
-	ip netns exec at_ns0 ping -c 1 10.1.1.200
-	ip netns exec at_ns0 iperf -sD -p 5200 > /dev/null
-	sleep 0.2
-	iperf -c 10.1.1.100 -n 5k -p 5200
-	cleanup
-}
-
-function cleanup {
-	set +ex
-	pkill iperf
-	ip netns delete at_ns0
-	ip link del veth1
-	ip link del ipip11
-	ip link del gretap11
-	ip link del ip6gre11
-	ip link del ip6gretap11
-	ip link del vxlan11
-	ip link del geneve11
-	ip link del erspan11
-	ip link del ip6erspan11
-	pkill tcpdump
-	pkill cat
-	set -ex
-}
-
-trap cleanup 0 2 3 6 9
-cleanup
-echo "Testing GRE tunnel..."
-test_gre
-echo "Testing IP6GRE tunnel..."
-test_ip6gre
-echo "Testing IP6GRETAP tunnel..."
-test_ip6gretap
-echo "Testing ERSPAN tunnel..."
-test_erspan v1
-test_erspan v2
-echo "Testing IP6ERSPAN tunnel..."
-test_ip6erspan v1
-test_ip6erspan v2
-echo "Testing VXLAN tunnel..."
-test_vxlan
-echo "Testing GENEVE tunnel..."
-test_geneve
-echo "Testing IPIP tunnel..."
-test_ipip
-echo "*** PASS ***"
diff --git a/samples/sockmap/Makefile b/samples/sockmap/Makefile
deleted file mode 100644
index fa53f4d77834..000000000000
--- a/samples/sockmap/Makefile
+++ /dev/null
@@ -1,78 +0,0 @@
-# List of programs to build
-hostprogs-y := sockmap
-
-# Libbpf dependencies
-LIBBPF := ../../tools/lib/bpf/bpf.o ../../tools/lib/bpf/nlattr.o
-
-HOSTCFLAGS += -I$(objtree)/usr/include
-HOSTCFLAGS += -I$(srctree)/tools/lib/
-HOSTCFLAGS += -I$(srctree)/tools/testing/selftests/bpf/
-HOSTCFLAGS += -I$(srctree)/tools/lib/ -I$(srctree)/tools/include
-HOSTCFLAGS += -I$(srctree)/tools/perf
-
-sockmap-objs := ../bpf/bpf_load.o $(LIBBPF) sockmap_user.o
-
-# Tell kbuild to always build the programs
-always := $(hostprogs-y)
-always += sockmap_kern.o
-
-HOSTLOADLIBES_sockmap += -lelf -lpthread
-
-# Allows pointing LLC/CLANG to a LLVM backend with bpf support, redefine on cmdline:
-#  make samples/bpf/ LLC=~/git/llvm/build/bin/llc CLANG=~/git/llvm/build/bin/clang
-LLC ?= llc
-CLANG ?= clang
-
-# Trick to allow make to be run from this directory
-all:
-	$(MAKE) -C ../../ $(CURDIR)/
-
-clean:
-	$(MAKE) -C ../../ M=$(CURDIR) clean
-	@rm -f *~
-
-$(obj)/syscall_nrs.s:	$(src)/syscall_nrs.c
-	$(call if_changed_dep,cc_s_c)
-
-$(obj)/syscall_nrs.h:	$(obj)/syscall_nrs.s FORCE
-	$(call filechk,offsets,__SYSCALL_NRS_H__)
-
-clean-files += syscall_nrs.h
-
-FORCE:
-
-
-# Verify LLVM compiler tools are available and bpf target is supported by llc
-.PHONY: verify_cmds verify_target_bpf $(CLANG) $(LLC)
-
-verify_cmds: $(CLANG) $(LLC)
-	@for TOOL in $^ ; do \
-		if ! (which -- "$${TOOL}" > /dev/null 2>&1); then \
-			echo "*** ERROR: Cannot find LLVM tool $${TOOL}" ;\
-			exit 1; \
-		else true; fi; \
-	done
-
-verify_target_bpf: verify_cmds
-	@if ! (${LLC} -march=bpf -mattr=help > /dev/null 2>&1); then \
-		echo "*** ERROR: LLVM (${LLC}) does not support 'bpf' target" ;\
-		echo "   NOTICE: LLVM version >= 3.7.1 required" ;\
-		exit 2; \
-	else true; fi
-
-$(src)/*.c: verify_target_bpf
-
-# asm/sysreg.h - inline assembly used by it is incompatible with llvm.
-# But, there is no easy way to fix it, so just exclude it since it is
-# useless for BPF samples.
-#
-# -target bpf option required with SK_MSG programs, this is to ensure
-#  reading 'void *' data types for data and data_end are __u64 reads.
-$(obj)/%.o: $(src)/%.c
-	$(CLANG) $(NOSTDINC_FLAGS) $(LINUXINCLUDE) $(EXTRA_CFLAGS) -I$(obj) \
-		-D__KERNEL__ -D__ASM_SYSREG_H -Wno-unused-value -Wno-pointer-sign \
-		-Wno-compare-distinct-pointer-types \
-		-Wno-gnu-variable-sized-type-not-at-end \
-		-Wno-address-of-packed-member -Wno-tautological-compare \
-		-Wno-unknown-warning-option -O2 -target bpf \
-		-emit-llvm -c $< -o -| $(LLC) -march=bpf -filetype=obj -o $@
diff --git a/samples/sockmap/sockmap_test.sh b/samples/sockmap/sockmap_test.sh
deleted file mode 100755
index ace75f070eb8..000000000000
--- a/samples/sockmap/sockmap_test.sh
+++ /dev/null
@@ -1,488 +0,0 @@
-#Test a bunch of positive cases to verify basic functionality
-for prog in  "--txmsg_redir --txmsg_skb" "--txmsg_redir --txmsg_ingress" "--txmsg" "--txmsg_redir" "--txmsg_redir --txmsg_ingress" "--txmsg_drop"; do
-for t in "sendmsg" "sendpage"; do
-for r in 1 10 100; do
-	for i in 1 10 100; do
-		for l in 1 10 100; do
-			TEST="./sockmap --cgroup /mnt/cgroup2/ -t $t -r $r -i $i -l $l $prog"
-			echo $TEST
-			$TEST
-			sleep 2
-		done
-	done
-done
-done
-done
-
-#Test max iov
-t="sendmsg"
-r=1
-i=1024
-l=1
-prog="--txmsg"
-
-TEST="./sockmap --cgroup /mnt/cgroup2/ -t $t -r $r -i $i -l $l $prog"
-echo $TEST
-$TEST
-sleep 2
-prog="--txmsg_redir"
-TEST="./sockmap --cgroup /mnt/cgroup2/ -t $t -r $r -i $i -l $l $prog"
-echo $TEST
-$TEST
-
-# Test max iov with 1k send
-
-t="sendmsg"
-r=1
-i=1024
-l=1024
-prog="--txmsg"
-
-TEST="./sockmap --cgroup /mnt/cgroup2/ -t $t -r $r -i $i -l $l $prog"
-echo $TEST
-$TEST
-sleep 2
-prog="--txmsg_redir"
-TEST="./sockmap --cgroup /mnt/cgroup2/ -t $t -r $r -i $i -l $l $prog"
-echo $TEST
-$TEST
-sleep 2
-
-# Test apply with 1B
-r=1
-i=1024
-l=1024
-prog="--txmsg_apply 1"
-
-for t in "sendmsg" "sendpage"; do
-	TEST="./sockmap --cgroup /mnt/cgroup2/ -t $t -r $r -i $i -l $l $prog"
-	echo $TEST
-	$TEST
-	sleep 2
-done
-
-# Test apply with larger value than send
-r=1
-i=8
-l=1024
-prog="--txmsg_apply 2048"
-
-for t in "sendmsg" "sendpage"; do
-	TEST="./sockmap --cgroup /mnt/cgroup2/ -t $t -r $r -i $i -l $l $prog"
-	echo $TEST
-	$TEST
-	sleep 2
-done
-
-# Test apply with apply that never reaches limit
-r=1024
-i=1
-l=1
-prog="--txmsg_apply 2048"
-
-for t in "sendmsg" "sendpage"; do
-	TEST="./sockmap --cgroup /mnt/cgroup2/ -t $t -r $r -i $i -l $l $prog"
-	echo $TEST
-	$TEST
-	sleep 2
-done
-
-# Test apply and redirect with 1B
-r=1
-i=1024
-l=1024
-prog="--txmsg_redir --txmsg_apply 1"
-
-for t in "sendmsg" "sendpage"; do
-	TEST="./sockmap --cgroup /mnt/cgroup2/ -t $t -r $r -i $i -l $l $prog"
-	echo $TEST
-	$TEST
-	sleep 2
-done
-
-prog="--txmsg_redir --txmsg_apply 1 --txmsg_ingress"
-
-for t in "sendmsg" "sendpage"; do
-	TEST="./sockmap --cgroup /mnt/cgroup2/ -t $t -r $r -i $i -l $l $prog"
-	echo $TEST
-	$TEST
-	sleep 2
-done
-
-prog="--txmsg_redir --txmsg_apply 1 --txmsg_skb"
-
-for t in "sendmsg" "sendpage"; do
-	TEST="./sockmap --cgroup /mnt/cgroup2/ -t $t -r $r -i $i -l $l $prog"
-	echo $TEST
-	$TEST
-	sleep 2
-done
-
-
-# Test apply and redirect with larger value than send
-r=1
-i=8
-l=1024
-prog="--txmsg_redir --txmsg_apply 2048"
-
-for t in "sendmsg" "sendpage"; do
-	TEST="./sockmap --cgroup /mnt/cgroup2/ -t $t -r $r -i $i -l $l $prog"
-	echo $TEST
-	$TEST
-	sleep 2
-done
-
-prog="--txmsg_redir --txmsg_apply 2048 --txmsg_ingress"
-
-for t in "sendmsg" "sendpage"; do
-	TEST="./sockmap --cgroup /mnt/cgroup2/ -t $t -r $r -i $i -l $l $prog"
-	echo $TEST
-	$TEST
-	sleep 2
-done
-
-prog="--txmsg_redir --txmsg_apply 2048 --txmsg_skb"
-
-for t in "sendmsg" "sendpage"; do
-	TEST="./sockmap --cgroup /mnt/cgroup2/ -t $t -r $r -i $i -l $l $prog"
-	echo $TEST
-	$TEST
-	sleep 2
-done
-
-
-# Test apply and redirect with apply that never reaches limit
-r=1024
-i=1
-l=1
-prog="--txmsg_apply 2048"
-
-for t in "sendmsg" "sendpage"; do
-	TEST="./sockmap --cgroup /mnt/cgroup2/ -t $t -r $r -i $i -l $l $prog"
-	echo $TEST
-	$TEST
-	sleep 2
-done
-
-# Test cork with 1B not really useful but test it anyways
-r=1
-i=1024
-l=1024
-prog="--txmsg_cork 1"
-
-for t in "sendpage" "sendmsg"; do
-	TEST="./sockmap --cgroup /mnt/cgroup2/ -t $t -r $r -i $i -l $l $prog"
-	echo $TEST
-	$TEST
-	sleep 2
-done
-
-# Test cork with a more reasonable 100B
-r=1
-i=1000
-l=1000
-prog="--txmsg_cork 100"
-
-for t in "sendpage" "sendmsg"; do
-	TEST="./sockmap --cgroup /mnt/cgroup2/ -t $t -r $r -i $i -l $l $prog"
-	echo $TEST
-	$TEST
-	sleep 2
-done
-
-# Test cork with larger value than send
-r=1
-i=8
-l=1024
-prog="--txmsg_cork 2048"
-
-for t in "sendpage" "sendmsg"; do
-	TEST="./sockmap --cgroup /mnt/cgroup2/ -t $t -r $r -i $i -l $l $prog"
-	echo $TEST
-	$TEST
-	sleep 2
-done
-
-# Test cork with cork that never reaches limit
-r=1024
-i=1
-l=1
-prog="--txmsg_cork 2048"
-
-for t in "sendpage" "sendmsg"; do
-	TEST="./sockmap --cgroup /mnt/cgroup2/ -t $t -r $r -i $i -l $l $prog"
-	echo $TEST
-	$TEST
-	sleep 2
-done
-
-r=1
-i=1024
-l=1024
-prog="--txmsg_redir --txmsg_cork 1"
-
-for t in "sendpage" "sendmsg"; do
-	TEST="./sockmap --cgroup /mnt/cgroup2/ -t $t -r $r -i $i -l $l $prog"
-	echo $TEST
-	$TEST
-	sleep 2
-done
-
-# Test cork with a more reasonable 100B
-r=1
-i=1000
-l=1000
-prog="--txmsg_redir --txmsg_cork 100"
-
-for t in "sendpage" "sendmsg"; do
-	TEST="./sockmap --cgroup /mnt/cgroup2/ -t $t -r $r -i $i -l $l $prog"
-	echo $TEST
-	$TEST
-	sleep 2
-done
-
-# Test cork with larger value than send
-r=1
-i=8
-l=1024
-prog="--txmsg_redir --txmsg_cork 2048"
-
-for t in "sendpage" "sendmsg"; do
-	TEST="./sockmap --cgroup /mnt/cgroup2/ -t $t -r $r -i $i -l $l $prog"
-	echo $TEST
-	$TEST
-	sleep 2
-done
-
-# Test cork with cork that never reaches limit
-r=1024
-i=1
-l=1
-prog="--txmsg_cork 2048"
-
-for t in "sendpage" "sendmsg"; do
-	TEST="./sockmap --cgroup /mnt/cgroup2/ -t $t -r $r -i $i -l $l $prog"
-	echo $TEST
-	$TEST
-	sleep 2
-done
-
-
-# mix and match cork and apply not really useful but valid programs
-
-# Test apply < cork
-r=100
-i=1
-l=5
-prog="--txmsg_apply 10 --txmsg_cork 100"
-for t in "sendpage" "sendmsg"; do
-	TEST="./sockmap --cgroup /mnt/cgroup2/ -t $t -r $r -i $i -l $l $prog"
-	echo $TEST
-	$TEST
-	sleep 2
-done
-
-# Try again with larger sizes so we hit overflow case
-r=100
-i=1000
-l=2048
-prog="--txmsg_apply 4096 --txmsg_cork 8096"
-for t in "sendpage" "sendmsg"; do
-	TEST="./sockmap --cgroup /mnt/cgroup2/ -t $t -r $r -i $i -l $l $prog"
-	echo $TEST
-	$TEST
-	sleep 2
-done
-
-# Test apply > cork
-r=100
-i=1
-l=5
-prog="--txmsg_apply 100 --txmsg_cork 10"
-for t in "sendpage" "sendmsg"; do
-	TEST="./sockmap --cgroup /mnt/cgroup2/ -t $t -r $r -i $i -l $l $prog"
-	echo $TEST
-	$TEST
-	sleep 2
-done
-
-# Again with larger sizes so we hit overflow cases
-r=100
-i=1000
-l=2048
-prog="--txmsg_apply 8096 --txmsg_cork 4096"
-for t in "sendpage" "sendmsg"; do
-	TEST="./sockmap --cgroup /mnt/cgroup2/ -t $t -r $r -i $i -l $l $prog"
-	echo $TEST
-	$TEST
-	sleep 2
-done
-
-
-# Test apply = cork
-r=100
-i=1
-l=5
-prog="--txmsg_apply 10 --txmsg_cork 10"
-for t in "sendpage" "sendmsg"; do
-	TEST="./sockmap --cgroup /mnt/cgroup2/ -t $t -r $r -i $i -l $l $prog"
-	echo $TEST
-	$TEST
-	sleep 2
-done
-
-r=100
-i=1000
-l=2048
-prog="--txmsg_apply 4096 --txmsg_cork 4096"
-for t in "sendpage" "sendmsg"; do
-	TEST="./sockmap --cgroup /mnt/cgroup2/ -t $t -r $r -i $i -l $l $prog"
-	echo $TEST
-	$TEST
-	sleep 2
-done
-
-# Test apply < cork
-r=100
-i=1
-l=5
-prog="--txmsg_redir --txmsg_apply 10 --txmsg_cork 100"
-for t in "sendpage" "sendmsg"; do
-	TEST="./sockmap --cgroup /mnt/cgroup2/ -t $t -r $r -i $i -l $l $prog"
-	echo $TEST
-	$TEST
-	sleep 2
-done
-
-# Try again with larger sizes so we hit overflow case
-r=100
-i=1000
-l=2048
-prog="--txmsg_redir --txmsg_apply 4096 --txmsg_cork 8096"
-for t in "sendpage" "sendmsg"; do
-	TEST="./sockmap --cgroup /mnt/cgroup2/ -t $t -r $r -i $i -l $l $prog"
-	echo $TEST
-	$TEST
-	sleep 2
-done
-
-# Test apply > cork
-r=100
-i=1
-l=5
-prog="--txmsg_redir --txmsg_apply 100 --txmsg_cork 10"
-for t in "sendpage" "sendmsg"; do
-	TEST="./sockmap --cgroup /mnt/cgroup2/ -t $t -r $r -i $i -l $l $prog"
-	echo $TEST
-	$TEST
-	sleep 2
-done
-
-# Again with larger sizes so we hit overflow cases
-r=100
-i=1000
-l=2048
-prog="--txmsg_redir --txmsg_apply 8096 --txmsg_cork 4096"
-for t in "sendpage" "sendmsg"; do
-	TEST="./sockmap --cgroup /mnt/cgroup2/ -t $t -r $r -i $i -l $l $prog"
-	echo $TEST
-	$TEST
-	sleep 2
-done
-
-
-# Test apply = cork
-r=100
-i=1
-l=5
-prog="--txmsg_redir --txmsg_apply 10 --txmsg_cork 10"
-for t in "sendpage" "sendmsg"; do
-	TEST="./sockmap --cgroup /mnt/cgroup2/ -t $t -r $r -i $i -l $l $prog"
-	echo $TEST
-	$TEST
-	sleep 2
-done
-
-r=100
-i=1000
-l=2048
-prog="--txmsg_redir --txmsg_apply 4096 --txmsg_cork 4096"
-for t in "sendpage" "sendmsg"; do
-	TEST="./sockmap --cgroup /mnt/cgroup2/ -t $t -r $r -i $i -l $l $prog"
-	echo $TEST
-	$TEST
-	sleep 2
-done
-
-# Tests for bpf_msg_pull_data()
-for i in `seq 99 100 1600`; do
-	TEST="./sockmap --cgroup /mnt/cgroup2/ -t sendpage -r 16 -i 1 -l 100 \
-		--txmsg --txmsg_start 0 --txmsg_end $i --txmsg_cork 1600"
-	echo $TEST
-	$TEST
-	sleep 2
-done
-
-for i in `seq 199 100 1600`; do
-	TEST="./sockmap --cgroup /mnt/cgroup2/ -t sendpage -r 16 -i 1 -l 100 \
-		--txmsg --txmsg_start 100 --txmsg_end $i --txmsg_cork 1600"
-	echo $TEST
-	$TEST
-	sleep 2
-done
-
-TEST="./sockmap --cgroup /mnt/cgroup2/ -t sendpage -r 16 -i 1 -l 100 \
-	--txmsg --txmsg_start 1500 --txmsg_end 1600 --txmsg_cork 1600"
-echo $TEST
-$TEST
-sleep 2
-
-TEST="./sockmap --cgroup /mnt/cgroup2/ -t sendpage -r 16 -i 1 -l 100 \
-	--txmsg --txmsg_start 1111 --txmsg_end 1112 --txmsg_cork 1600"
-echo $TEST
-$TEST
-sleep 2
-
-TEST="./sockmap --cgroup /mnt/cgroup2/ -t sendpage -r 16 -i 1 -l 100 \
-	--txmsg --txmsg_start 1111 --txmsg_end 0 --txmsg_cork 1600"
-echo $TEST
-$TEST
-sleep 2
-
-TEST="./sockmap --cgroup /mnt/cgroup2/ -t sendpage -r 16 -i 1 -l 100 \
-	--txmsg --txmsg_start 0 --txmsg_end 1601 --txmsg_cork 1600"
-echo $TEST
-$TEST
-sleep 2
-
-TEST="./sockmap --cgroup /mnt/cgroup2/ -t sendpage -r 16 -i 1 -l 100 \
-	--txmsg --txmsg_start 0 --txmsg_end 1601 --txmsg_cork 1602"
-echo $TEST
-$TEST
-sleep 2
-
-# Run through gamut again with start and end
-for prog in "--txmsg" "--txmsg_redir" "--txmsg_drop"; do
-for t in "sendmsg" "sendpage"; do
-for r in 1 10 100; do
-	for i in 1 10 100; do
-		for l in 1 10 100; do
-			TEST="./sockmap --cgroup /mnt/cgroup2/ -t $t -r $r -i $i -l $l $prog --txmsg_start 1 --txmsg_end 2"
-			echo $TEST
-			$TEST
-			sleep 2
-		done
-	done
-done
-done
-done
-
-# Some specific tests to cover specific code paths
-./sockmap --cgroup /mnt/cgroup2/ -t sendpage \
-	-r 5 -i 1 -l 1 --txmsg_redir --txmsg_cork 5 --txmsg_apply 3
-./sockmap --cgroup /mnt/cgroup2/ -t sendmsg \
-	-r 5 -i 1 -l 1 --txmsg_redir --txmsg_cork 5 --txmsg_apply 3
-./sockmap --cgroup /mnt/cgroup2/ -t sendpage \
-	-r 5 -i 1 -l 1 --txmsg_redir --txmsg_cork 5 --txmsg_apply 5
-./sockmap --cgroup /mnt/cgroup2/ -t sendmsg \
-	-r 5 -i 1 -l 1 --txmsg_redir --txmsg_cork 5 --txmsg_apply 5
diff --git a/scripts/bpf_helpers_doc.py b/scripts/bpf_helpers_doc.py
new file mode 100755
index 000000000000..30ba0fee36e4
--- /dev/null
+++ b/scripts/bpf_helpers_doc.py
@@ -0,0 +1,421 @@
+#!/usr/bin/python3
+# SPDX-License-Identifier: GPL-2.0-only
+#
+# Copyright (C) 2018 Netronome Systems, Inc.
+
+# In case user attempts to run with Python 2.
+from __future__ import print_function
+
+import argparse
+import re
+import sys, os
+
+class NoHelperFound(BaseException):
+    pass
+
+class ParsingError(BaseException):
+    def __init__(self, line='<line not provided>', reader=None):
+        if reader:
+            BaseException.__init__(self,
+                                   'Error at file offset %d, parsing line: %s' %
+                                   (reader.tell(), line))
+        else:
+            BaseException.__init__(self, 'Error parsing line: %s' % line)
+
+class Helper(object):
+    """
+    An object representing the description of an eBPF helper function.
+    @proto: function prototype of the helper function
+    @desc: textual description of the helper function
+    @ret: description of the return value of the helper function
+    """
+    def __init__(self, proto='', desc='', ret=''):
+        self.proto = proto
+        self.desc = desc
+        self.ret = ret
+
+    def proto_break_down(self):
+        """
+        Break down helper function protocol into smaller chunks: return type,
+        name, distincts arguments.
+        """
+        arg_re = re.compile('^((const )?(struct )?(\w+|...))( (\**)(\w+))?$')
+        res = {}
+        proto_re = re.compile('^(.+) (\**)(\w+)\(((([^,]+)(, )?){1,5})\)$')
+
+        capture = proto_re.match(self.proto)
+        res['ret_type'] = capture.group(1)
+        res['ret_star'] = capture.group(2)
+        res['name']     = capture.group(3)
+        res['args'] = []
+
+        args    = capture.group(4).split(', ')
+        for a in args:
+            capture = arg_re.match(a)
+            res['args'].append({
+                'type' : capture.group(1),
+                'star' : capture.group(6),
+                'name' : capture.group(7)
+            })
+
+        return res
+
+class HeaderParser(object):
+    """
+    An object used to parse a file in order to extract the documentation of a
+    list of eBPF helper functions. All the helpers that can be retrieved are
+    stored as Helper object, in the self.helpers() array.
+    @filename: name of file to parse, usually include/uapi/linux/bpf.h in the
+               kernel tree
+    """
+    def __init__(self, filename):
+        self.reader = open(filename, 'r')
+        self.line = ''
+        self.helpers = []
+
+    def parse_helper(self):
+        proto    = self.parse_proto()
+        desc     = self.parse_desc()
+        ret      = self.parse_ret()
+        return Helper(proto=proto, desc=desc, ret=ret)
+
+    def parse_proto(self):
+        # Argument can be of shape:
+        #   - "void"
+        #   - "type  name"
+        #   - "type *name"
+        #   - Same as above, with "const" and/or "struct" in front of type
+        #   - "..." (undefined number of arguments, for bpf_trace_printk())
+        # There is at least one term ("void"), and at most five arguments.
+        p = re.compile('^ \* ((.+) \**\w+\((((const )?(struct )?(\w+|\.\.\.)( \**\w+)?)(, )?){1,5}\))$')
+        capture = p.match(self.line)
+        if not capture:
+            raise NoHelperFound
+        self.line = self.reader.readline()
+        return capture.group(1)
+
+    def parse_desc(self):
+        p = re.compile('^ \* \tDescription$')
+        capture = p.match(self.line)
+        if not capture:
+            # Helper can have empty description and we might be parsing another
+            # attribute: return but do not consume.
+            return ''
+        # Description can be several lines, some of them possibly empty, and it
+        # stops when another subsection title is met.
+        desc = ''
+        while True:
+            self.line = self.reader.readline()
+            if self.line == ' *\n':
+                desc += '\n'
+            else:
+                p = re.compile('^ \* \t\t(.*)')
+                capture = p.match(self.line)
+                if capture:
+                    desc += capture.group(1) + '\n'
+                else:
+                    break
+        return desc
+
+    def parse_ret(self):
+        p = re.compile('^ \* \tReturn$')
+        capture = p.match(self.line)
+        if not capture:
+            # Helper can have empty retval and we might be parsing another
+            # attribute: return but do not consume.
+            return ''
+        # Return value description can be several lines, some of them possibly
+        # empty, and it stops when another subsection title is met.
+        ret = ''
+        while True:
+            self.line = self.reader.readline()
+            if self.line == ' *\n':
+                ret += '\n'
+            else:
+                p = re.compile('^ \* \t\t(.*)')
+                capture = p.match(self.line)
+                if capture:
+                    ret += capture.group(1) + '\n'
+                else:
+                    break
+        return ret
+
+    def run(self):
+        # Advance to start of helper function descriptions.
+        offset = self.reader.read().find('* Start of BPF helper function descriptions:')
+        if offset == -1:
+            raise Exception('Could not find start of eBPF helper descriptions list')
+        self.reader.seek(offset)
+        self.reader.readline()
+        self.reader.readline()
+        self.line = self.reader.readline()
+
+        while True:
+            try:
+                helper = self.parse_helper()
+                self.helpers.append(helper)
+            except NoHelperFound:
+                break
+
+        self.reader.close()
+        print('Parsed description of %d helper function(s)' % len(self.helpers),
+              file=sys.stderr)
+
+###############################################################################
+
+class Printer(object):
+    """
+    A generic class for printers. Printers should be created with an array of
+    Helper objects, and implement a way to print them in the desired fashion.
+    @helpers: array of Helper objects to print to standard output
+    """
+    def __init__(self, helpers):
+        self.helpers = helpers
+
+    def print_header(self):
+        pass
+
+    def print_footer(self):
+        pass
+
+    def print_one(self, helper):
+        pass
+
+    def print_all(self):
+        self.print_header()
+        for helper in self.helpers:
+            self.print_one(helper)
+        self.print_footer()
+
+class PrinterRST(Printer):
+    """
+    A printer for dumping collected information about helpers as a ReStructured
+    Text page compatible with the rst2man program, which can be used to
+    generate a manual page for the helpers.
+    @helpers: array of Helper objects to print to standard output
+    """
+    def print_header(self):
+        header = '''\
+.. Copyright (C) All BPF authors and contributors from 2014 to present.
+.. See git log include/uapi/linux/bpf.h in kernel tree for details.
+.. 
+.. %%%LICENSE_START(VERBATIM)
+.. Permission is granted to make and distribute verbatim copies of this
+.. manual provided the copyright notice and this permission notice are
+.. preserved on all copies.
+.. 
+.. Permission is granted to copy and distribute modified versions of this
+.. manual under the conditions for verbatim copying, provided that the
+.. entire resulting derived work is distributed under the terms of a
+.. permission notice identical to this one.
+.. 
+.. Since the Linux kernel and libraries are constantly changing, this
+.. manual page may be incorrect or out-of-date.  The author(s) assume no
+.. responsibility for errors or omissions, or for damages resulting from
+.. the use of the information contained herein.  The author(s) may not
+.. have taken the same level of care in the production of this manual,
+.. which is licensed free of charge, as they might when working
+.. professionally.
+.. 
+.. Formatted or processed versions of this manual, if unaccompanied by
+.. the source, must acknowledge the copyright and authors of this work.
+.. %%%LICENSE_END
+.. 
+.. Please do not edit this file. It was generated from the documentation
+.. located in file include/uapi/linux/bpf.h of the Linux kernel sources
+.. (helpers description), and from scripts/bpf_helpers_doc.py in the same
+.. repository (header and footer).
+
+===========
+BPF-HELPERS
+===========
+-------------------------------------------------------------------------------
+list of eBPF helper functions
+-------------------------------------------------------------------------------
+
+:Manual section: 7
+
+DESCRIPTION
+===========
+
+The extended Berkeley Packet Filter (eBPF) subsystem consists in programs
+written in a pseudo-assembly language, then attached to one of the several
+kernel hooks and run in reaction of specific events. This framework differs
+from the older, "classic" BPF (or "cBPF") in several aspects, one of them being
+the ability to call special functions (or "helpers") from within a program.
+These functions are restricted to a white-list of helpers defined in the
+kernel.
+
+These helpers are used by eBPF programs to interact with the system, or with
+the context in which they work. For instance, they can be used to print
+debugging messages, to get the time since the system was booted, to interact
+with eBPF maps, or to manipulate network packets. Since there are several eBPF
+program types, and that they do not run in the same context, each program type
+can only call a subset of those helpers.
+
+Due to eBPF conventions, a helper can not have more than five arguments.
+
+Internally, eBPF programs call directly into the compiled helper functions
+without requiring any foreign-function interface. As a result, calling helpers
+introduces no overhead, thus offering excellent performance.
+
+This document is an attempt to list and document the helpers available to eBPF
+developers. They are sorted by chronological order (the oldest helpers in the
+kernel at the top).
+
+HELPERS
+=======
+'''
+        print(header)
+
+    def print_footer(self):
+        footer = '''
+EXAMPLES
+========
+
+Example usage for most of the eBPF helpers listed in this manual page are
+available within the Linux kernel sources, at the following locations:
+
+* *samples/bpf/*
+* *tools/testing/selftests/bpf/*
+
+LICENSE
+=======
+
+eBPF programs can have an associated license, passed along with the bytecode
+instructions to the kernel when the programs are loaded. The format for that
+string is identical to the one in use for kernel modules (Dual licenses, such
+as "Dual BSD/GPL", may be used). Some helper functions are only accessible to
+programs that are compatible with the GNU Privacy License (GPL).
+
+In order to use such helpers, the eBPF program must be loaded with the correct
+license string passed (via **attr**) to the **bpf**\ () system call, and this
+generally translates into the C source code of the program containing a line
+similar to the following:
+
+::
+
+	char ____license[] __attribute__((section("license"), used)) = "GPL";
+
+IMPLEMENTATION
+==============
+
+This manual page is an effort to document the existing eBPF helper functions.
+But as of this writing, the BPF sub-system is under heavy development. New eBPF
+program or map types are added, along with new helper functions. Some helpers
+are occasionally made available for additional program types. So in spite of
+the efforts of the community, this page might not be up-to-date. If you want to
+check by yourself what helper functions exist in your kernel, or what types of
+programs they can support, here are some files among the kernel tree that you
+may be interested in:
+
+* *include/uapi/linux/bpf.h* is the main BPF header. It contains the full list
+  of all helper functions, as well as many other BPF definitions including most
+  of the flags, structs or constants used by the helpers.
+* *net/core/filter.c* contains the definition of most network-related helper
+  functions, and the list of program types from which they can be used.
+* *kernel/trace/bpf_trace.c* is the equivalent for most tracing program-related
+  helpers.
+* *kernel/bpf/verifier.c* contains the functions used to check that valid types
+  of eBPF maps are used with a given helper function.
+* *kernel/bpf/* directory contains other files in which additional helpers are
+  defined (for cgroups, sockmaps, etc.).
+
+Compatibility between helper functions and program types can generally be found
+in the files where helper functions are defined. Look for the **struct
+bpf_func_proto** objects and for functions returning them: these functions
+contain a list of helpers that a given program type can call. Note that the
+**default:** label of the **switch ... case** used to filter helpers can call
+other functions, themselves allowing access to additional helpers. The
+requirement for GPL license is also in those **struct bpf_func_proto**.
+
+Compatibility between helper functions and map types can be found in the
+**check_map_func_compatibility**\ () function in file *kernel/bpf/verifier.c*.
+
+Helper functions that invalidate the checks on **data** and **data_end**
+pointers for network processing are listed in function
+**bpf_helper_changes_pkt_data**\ () in file *net/core/filter.c*.
+
+SEE ALSO
+========
+
+**bpf**\ (2),
+**cgroups**\ (7),
+**ip**\ (8),
+**perf_event_open**\ (2),
+**sendmsg**\ (2),
+**socket**\ (7),
+**tc-bpf**\ (8)'''
+        print(footer)
+
+    def print_proto(self, helper):
+        """
+        Format function protocol with bold and italics markers. This makes RST
+        file less readable, but gives nice results in the manual page.
+        """
+        proto = helper.proto_break_down()
+
+        print('**%s %s%s(' % (proto['ret_type'],
+                              proto['ret_star'].replace('*', '\\*'),
+                              proto['name']),
+              end='')
+
+        comma = ''
+        for a in proto['args']:
+            one_arg = '{}{}'.format(comma, a['type'])
+            if a['name']:
+                if a['star']:
+                    one_arg += ' {}**\ '.format(a['star'].replace('*', '\\*'))
+                else:
+                    one_arg += '** '
+                one_arg += '*{}*\\ **'.format(a['name'])
+            comma = ', '
+            print(one_arg, end='')
+
+        print(')**')
+
+    def print_one(self, helper):
+        self.print_proto(helper)
+
+        if (helper.desc):
+            print('\tDescription')
+            # Do not strip all newline characters: formatted code at the end of
+            # a section must be followed by a blank line.
+            for line in re.sub('\n$', '', helper.desc, count=1).split('\n'):
+                print('{}{}'.format('\t\t' if line else '', line))
+
+        if (helper.ret):
+            print('\tReturn')
+            for line in helper.ret.rstrip().split('\n'):
+                print('{}{}'.format('\t\t' if line else '', line))
+
+        print('')
+
+###############################################################################
+
+# If script is launched from scripts/ from kernel tree and can access
+# ../include/uapi/linux/bpf.h, use it as a default name for the file to parse,
+# otherwise the --filename argument will be required from the command line.
+script = os.path.abspath(sys.argv[0])
+linuxRoot = os.path.dirname(os.path.dirname(script))
+bpfh = os.path.join(linuxRoot, 'include/uapi/linux/bpf.h')
+
+argParser = argparse.ArgumentParser(description="""
+Parse eBPF header file and generate documentation for eBPF helper functions.
+The RST-formatted output produced can be turned into a manual page with the
+rst2man utility.
+""")
+if (os.path.isfile(bpfh)):
+    argParser.add_argument('--filename', help='path to include/uapi/linux/bpf.h',
+                           default=bpfh)
+else:
+    argParser.add_argument('--filename', help='path to include/uapi/linux/bpf.h')
+args = argParser.parse_args()
+
+# Parse file.
+headerParser = HeaderParser(args.filename)
+headerParser.run()
+
+# Print formatted output to standard output.
+printer = PrinterRST(headerParser.helpers)
+printer.print_all()
diff --git a/tools/bpf/bpftool/Documentation/bpftool-prog.rst b/tools/bpf/bpftool/Documentation/bpftool-prog.rst
index 67ca6c69376c..43d34a5c3ec5 100644
--- a/tools/bpf/bpftool/Documentation/bpftool-prog.rst
+++ b/tools/bpf/bpftool/Documentation/bpftool-prog.rst
@@ -95,7 +95,7 @@ EXAMPLES
 **# bpftool prog show**
 ::
 
-  10: xdp  name some_prog  tag 005a3d2123620c8b
+  10: xdp  name some_prog  tag 005a3d2123620c8b  gpl
 	loaded_at Sep 29/20:11  uid 0
 	xlated 528B  jited 370B  memlock 4096B  map_ids 10
 
@@ -108,6 +108,7 @@ EXAMPLES
                 "id": 10,
                 "type": "xdp",
                 "tag": "005a3d2123620c8b",
+                "gpl_compatible": true,
                 "loaded_at": "Sep 29/20:11",
                 "uid": 0,
                 "bytes_xlated": 528,
diff --git a/tools/bpf/bpftool/prog.c b/tools/bpf/bpftool/prog.c
index 548adb9b7317..e71a0a11afde 100644
--- a/tools/bpf/bpftool/prog.c
+++ b/tools/bpf/bpftool/prog.c
@@ -235,6 +235,8 @@ static void print_prog_json(struct bpf_prog_info *info, int fd)
 		     info->tag[0], info->tag[1], info->tag[2], info->tag[3],
 		     info->tag[4], info->tag[5], info->tag[6], info->tag[7]);
 
+	jsonw_bool_field(json_wtr, "gpl_compatible", info->gpl_compatible);
+
 	print_dev_json(info->ifindex, info->netns_dev, info->netns_ino);
 
 	if (info->load_time) {
@@ -295,6 +297,7 @@ static void print_prog_plain(struct bpf_prog_info *info, int fd)
 	printf("tag ");
 	fprint_hex(stdout, info->tag, BPF_TAG_SIZE, "");
 	print_dev_plain(info->ifindex, info->netns_dev, info->netns_ino);
+	printf("%s", info->gpl_compatible ? "  gpl" : "");
 	printf("\n");
 
 	if (info->load_time) {
diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h
index c8383a289f7b..da77a9388947 100644
--- a/tools/include/uapi/linux/bpf.h
+++ b/tools/include/uapi/linux/bpf.h
@@ -377,403 +377,1396 @@ union bpf_attr {
 	};
 } __attribute__((aligned(8)));
 
-/* BPF helper function descriptions:
- *
- * void *bpf_map_lookup_elem(&map, &key)
- *     Return: Map value or NULL
- *
- * int bpf_map_update_elem(&map, &key, &value, flags)
- *     Return: 0 on success or negative error
- *
- * int bpf_map_delete_elem(&map, &key)
- *     Return: 0 on success or negative error
- *
- * int bpf_probe_read(void *dst, int size, void *src)
- *     Return: 0 on success or negative error
+/* The description below is an attempt at providing documentation to eBPF
+ * developers about the multiple available eBPF helper functions. It can be
+ * parsed and used to produce a manual page. The workflow is the following,
+ * and requires the rst2man utility:
+ *
+ *     $ ./scripts/bpf_helpers_doc.py \
+ *             --filename include/uapi/linux/bpf.h > /tmp/bpf-helpers.rst
+ *     $ rst2man /tmp/bpf-helpers.rst > /tmp/bpf-helpers.7
+ *     $ man /tmp/bpf-helpers.7
+ *
+ * Note that in order to produce this external documentation, some RST
+ * formatting is used in the descriptions to get "bold" and "italics" in
+ * manual pages. Also note that the few trailing white spaces are
+ * intentional, removing them would break paragraphs for rst2man.
+ *
+ * Start of BPF helper function descriptions:
+ *
+ * void *bpf_map_lookup_elem(struct bpf_map *map, const void *key)
+ * 	Description
+ * 		Perform a lookup in *map* for an entry associated to *key*.
+ * 	Return
+ * 		Map value associated to *key*, or **NULL** if no entry was
+ * 		found.
+ *
+ * int bpf_map_update_elem(struct bpf_map *map, const void *key, const void *value, u64 flags)
+ * 	Description
+ * 		Add or update the value of the entry associated to *key* in
+ * 		*map* with *value*. *flags* is one of:
+ *
+ * 		**BPF_NOEXIST**
+ * 			The entry for *key* must not exist in the map.
+ * 		**BPF_EXIST**
+ * 			The entry for *key* must already exist in the map.
+ * 		**BPF_ANY**
+ * 			No condition on the existence of the entry for *key*.
+ *
+ * 		Flag value **BPF_NOEXIST** cannot be used for maps of types
+ * 		**BPF_MAP_TYPE_ARRAY** or **BPF_MAP_TYPE_PERCPU_ARRAY**  (all
+ * 		elements always exist), the helper would return an error.
+ * 	Return
+ * 		0 on success, or a negative error in case of failure.
+ *
+ * int bpf_map_delete_elem(struct bpf_map *map, const void *key)
+ * 	Description
+ * 		Delete entry with *key* from *map*.
+ * 	Return
+ * 		0 on success, or a negative error in case of failure.
+ *
+ * int bpf_probe_read(void *dst, u32 size, const void *src)
+ * 	Description
+ * 		For tracing programs, safely attempt to read *size* bytes from
+ * 		address *src* and store the data in *dst*.
+ * 	Return
+ * 		0 on success, or a negative error in case of failure.
  *
  * u64 bpf_ktime_get_ns(void)
- *     Return: current ktime
- *
- * int bpf_trace_printk(const char *fmt, int fmt_size, ...)
- *     Return: length of buffer written or negative error
- *
- * u32 bpf_prandom_u32(void)
- *     Return: random value
- *
- * u32 bpf_raw_smp_processor_id(void)
- *     Return: SMP processor ID
- *
- * int bpf_skb_store_bytes(skb, offset, from, len, flags)
- *     store bytes into packet
- *     @skb: pointer to skb
- *     @offset: offset within packet from skb->mac_header
- *     @from: pointer where to copy bytes from
- *     @len: number of bytes to store into packet
- *     @flags: bit 0 - if true, recompute skb->csum
- *             other bits - reserved
- *     Return: 0 on success or negative error
- *
- * int bpf_l3_csum_replace(skb, offset, from, to, flags)
- *     recompute IP checksum
- *     @skb: pointer to skb
- *     @offset: offset within packet where IP checksum is located
- *     @from: old value of header field
- *     @to: new value of header field
- *     @flags: bits 0-3 - size of header field
- *             other bits - reserved
- *     Return: 0 on success or negative error
- *
- * int bpf_l4_csum_replace(skb, offset, from, to, flags)
- *     recompute TCP/UDP checksum
- *     @skb: pointer to skb
- *     @offset: offset within packet where TCP/UDP checksum is located
- *     @from: old value of header field
- *     @to: new value of header field
- *     @flags: bits 0-3 - size of header field
- *             bit 4 - is pseudo header
- *             other bits - reserved
- *     Return: 0 on success or negative error
- *
- * int bpf_tail_call(ctx, prog_array_map, index)
- *     jump into another BPF program
- *     @ctx: context pointer passed to next program
- *     @prog_array_map: pointer to map which type is BPF_MAP_TYPE_PROG_ARRAY
- *     @index: 32-bit index inside array that selects specific program to run
- *     Return: 0 on success or negative error
- *
- * int bpf_clone_redirect(skb, ifindex, flags)
- *     redirect to another netdev
- *     @skb: pointer to skb
- *     @ifindex: ifindex of the net device
- *     @flags: bit 0 - if set, redirect to ingress instead of egress
- *             other bits - reserved
- *     Return: 0 on success or negative error
+ * 	Description
+ * 		Return the time elapsed since system boot, in nanoseconds.
+ * 	Return
+ * 		Current *ktime*.
+ *
+ * int bpf_trace_printk(const char *fmt, u32 fmt_size, ...)
+ * 	Description
+ * 		This helper is a "printk()-like" facility for debugging. It
+ * 		prints a message defined by format *fmt* (of size *fmt_size*)
+ * 		to file *\/sys/kernel/debug/tracing/trace* from DebugFS, if
+ * 		available. It can take up to three additional **u64**
+ * 		arguments (as an eBPF helpers, the total number of arguments is
+ * 		limited to five).
+ *
+ * 		Each time the helper is called, it appends a line to the trace.
+ * 		The format of the trace is customizable, and the exact output
+ * 		one will get depends on the options set in
+ * 		*\/sys/kernel/debug/tracing/trace_options* (see also the
+ * 		*README* file under the same directory). However, it usually
+ * 		defaults to something like:
+ *
+ * 		::
+ *
+ * 			telnet-470   [001] .N.. 419421.045894: 0x00000001: <formatted msg>
+ *
+ * 		In the above:
+ *
+ * 			* ``telnet`` is the name of the current task.
+ * 			* ``470`` is the PID of the current task.
+ * 			* ``001`` is the CPU number on which the task is
+ * 			  running.
+ * 			* In ``.N..``, each character refers to a set of
+ * 			  options (whether irqs are enabled, scheduling
+ * 			  options, whether hard/softirqs are running, level of
+ * 			  preempt_disabled respectively). **N** means that
+ * 			  **TIF_NEED_RESCHED** and **PREEMPT_NEED_RESCHED**
+ * 			  are set.
+ * 			* ``419421.045894`` is a timestamp.
+ * 			* ``0x00000001`` is a fake value used by BPF for the
+ * 			  instruction pointer register.
+ * 			* ``<formatted msg>`` is the message formatted with
+ * 			  *fmt*.
+ *
+ * 		The conversion specifiers supported by *fmt* are similar, but
+ * 		more limited than for printk(). They are **%d**, **%i**,
+ * 		**%u**, **%x**, **%ld**, **%li**, **%lu**, **%lx**, **%lld**,
+ * 		**%lli**, **%llu**, **%llx**, **%p**, **%s**. No modifier (size
+ * 		of field, padding with zeroes, etc.) is available, and the
+ * 		helper will return **-EINVAL** (but print nothing) if it
+ * 		encounters an unknown specifier.
+ *
+ * 		Also, note that **bpf_trace_printk**\ () is slow, and should
+ * 		only be used for debugging purposes. For this reason, a notice
+ * 		bloc (spanning several lines) is printed to kernel logs and
+ * 		states that the helper should not be used "for production use"
+ * 		the first time this helper is used (or more precisely, when
+ * 		**trace_printk**\ () buffers are allocated). For passing values
+ * 		to user space, perf events should be preferred.
+ * 	Return
+ * 		The number of bytes written to the buffer, or a negative error
+ * 		in case of failure.
+ *
+ * u32 bpf_get_prandom_u32(void)
+ * 	Description
+ * 		Get a pseudo-random number.
+ *
+ * 		From a security point of view, this helper uses its own
+ * 		pseudo-random internal state, and cannot be used to infer the
+ * 		seed of other random functions in the kernel. However, it is
+ * 		essential to note that the generator used by the helper is not
+ * 		cryptographically secure.
+ * 	Return
+ * 		A random 32-bit unsigned value.
+ *
+ * u32 bpf_get_smp_processor_id(void)
+ * 	Description
+ * 		Get the SMP (symmetric multiprocessing) processor id. Note that
+ * 		all programs run with preemption disabled, which means that the
+ * 		SMP processor id is stable during all the execution of the
+ * 		program.
+ * 	Return
+ * 		The SMP id of the processor running the program.
+ *
+ * int bpf_skb_store_bytes(struct sk_buff *skb, u32 offset, const void *from, u32 len, u64 flags)
+ * 	Description
+ * 		Store *len* bytes from address *from* into the packet
+ * 		associated to *skb*, at *offset*. *flags* are a combination of
+ * 		**BPF_F_RECOMPUTE_CSUM** (automatically recompute the
+ * 		checksum for the packet after storing the bytes) and
+ * 		**BPF_F_INVALIDATE_HASH** (set *skb*\ **->hash**, *skb*\
+ * 		**->swhash** and *skb*\ **->l4hash** to 0).
+ *
+ * 		A call to this helper is susceptible to change the underlaying
+ * 		packet buffer. Therefore, at load time, all checks on pointers
+ * 		previously done by the verifier are invalidated and must be
+ * 		performed again, if the helper is used in combination with
+ * 		direct packet access.
+ * 	Return
+ * 		0 on success, or a negative error in case of failure.
+ *
+ * int bpf_l3_csum_replace(struct sk_buff *skb, u32 offset, u64 from, u64 to, u64 size)
+ * 	Description
+ * 		Recompute the layer 3 (e.g. IP) checksum for the packet
+ * 		associated to *skb*. Computation is incremental, so the helper
+ * 		must know the former value of the header field that was
+ * 		modified (*from*), the new value of this field (*to*), and the
+ * 		number of bytes (2 or 4) for this field, stored in *size*.
+ * 		Alternatively, it is possible to store the difference between
+ * 		the previous and the new values of the header field in *to*, by
+ * 		setting *from* and *size* to 0. For both methods, *offset*
+ * 		indicates the location of the IP checksum within the packet.
+ *
+ * 		This helper works in combination with **bpf_csum_diff**\ (),
+ * 		which does not update the checksum in-place, but offers more
+ * 		flexibility and can handle sizes larger than 2 or 4 for the
+ * 		checksum to update.
+ *
+ * 		A call to this helper is susceptible to change the underlaying
+ * 		packet buffer. Therefore, at load time, all checks on pointers
+ * 		previously done by the verifier are invalidated and must be
+ * 		performed again, if the helper is used in combination with
+ * 		direct packet access.
+ * 	Return
+ * 		0 on success, or a negative error in case of failure.
+ *
+ * int bpf_l4_csum_replace(struct sk_buff *skb, u32 offset, u64 from, u64 to, u64 flags)
+ * 	Description
+ * 		Recompute the layer 4 (e.g. TCP, UDP or ICMP) checksum for the
+ * 		packet associated to *skb*. Computation is incremental, so the
+ * 		helper must know the former value of the header field that was
+ * 		modified (*from*), the new value of this field (*to*), and the
+ * 		number of bytes (2 or 4) for this field, stored on the lowest
+ * 		four bits of *flags*. Alternatively, it is possible to store
+ * 		the difference between the previous and the new values of the
+ * 		header field in *to*, by setting *from* and the four lowest
+ * 		bits of *flags* to 0. For both methods, *offset* indicates the
+ * 		location of the IP checksum within the packet. In addition to
+ * 		the size of the field, *flags* can be added (bitwise OR) actual
+ * 		flags. With **BPF_F_MARK_MANGLED_0**, a null checksum is left
+ * 		untouched (unless **BPF_F_MARK_ENFORCE** is added as well), and
+ * 		for updates resulting in a null checksum the value is set to
+ * 		**CSUM_MANGLED_0** instead. Flag **BPF_F_PSEUDO_HDR** indicates
+ * 		the checksum is to be computed against a pseudo-header.
+ *
+ * 		This helper works in combination with **bpf_csum_diff**\ (),
+ * 		which does not update the checksum in-place, but offers more
+ * 		flexibility and can handle sizes larger than 2 or 4 for the
+ * 		checksum to update.
+ *
+ * 		A call to this helper is susceptible to change the underlaying
+ * 		packet buffer. Therefore, at load time, all checks on pointers
+ * 		previously done by the verifier are invalidated and must be
+ * 		performed again, if the helper is used in combination with
+ * 		direct packet access.
+ * 	Return
+ * 		0 on success, or a negative error in case of failure.
+ *
+ * int bpf_tail_call(void *ctx, struct bpf_map *prog_array_map, u32 index)
+ * 	Description
+ * 		This special helper is used to trigger a "tail call", or in
+ * 		other words, to jump into another eBPF program. The same stack
+ * 		frame is used (but values on stack and in registers for the
+ * 		caller are not accessible to the callee). This mechanism allows
+ * 		for program chaining, either for raising the maximum number of
+ * 		available eBPF instructions, or to execute given programs in
+ * 		conditional blocks. For security reasons, there is an upper
+ * 		limit to the number of successive tail calls that can be
+ * 		performed.
+ *
+ * 		Upon call of this helper, the program attempts to jump into a
+ * 		program referenced at index *index* in *prog_array_map*, a
+ * 		special map of type **BPF_MAP_TYPE_PROG_ARRAY**, and passes
+ * 		*ctx*, a pointer to the context.
+ *
+ * 		If the call succeeds, the kernel immediately runs the first
+ * 		instruction of the new program. This is not a function call,
+ * 		and it never returns to the previous program. If the call
+ * 		fails, then the helper has no effect, and the caller continues
+ * 		to run its subsequent instructions. A call can fail if the
+ * 		destination program for the jump does not exist (i.e. *index*
+ * 		is superior to the number of entries in *prog_array_map*), or
+ * 		if the maximum number of tail calls has been reached for this
+ * 		chain of programs. This limit is defined in the kernel by the
+ * 		macro **MAX_TAIL_CALL_CNT** (not accessible to user space),
+ * 		which is currently set to 32.
+ * 	Return
+ * 		0 on success, or a negative error in case of failure.
+ *
+ * int bpf_clone_redirect(struct sk_buff *skb, u32 ifindex, u64 flags)
+ * 	Description
+ * 		Clone and redirect the packet associated to *skb* to another
+ * 		net device of index *ifindex*. Both ingress and egress
+ * 		interfaces can be used for redirection. The **BPF_F_INGRESS**
+ * 		value in *flags* is used to make the distinction (ingress path
+ * 		is selected if the flag is present, egress path otherwise).
+ * 		This is the only flag supported for now.
+ *
+ * 		In comparison with **bpf_redirect**\ () helper,
+ * 		**bpf_clone_redirect**\ () has the associated cost of
+ * 		duplicating the packet buffer, but this can be executed out of
+ * 		the eBPF program. Conversely, **bpf_redirect**\ () is more
+ * 		efficient, but it is handled through an action code where the
+ * 		redirection happens only after the eBPF program has returned.
+ *
+ * 		A call to this helper is susceptible to change the underlaying
+ * 		packet buffer. Therefore, at load time, all checks on pointers
+ * 		previously done by the verifier are invalidated and must be
+ * 		performed again, if the helper is used in combination with
+ * 		direct packet access.
+ * 	Return
+ * 		0 on success, or a negative error in case of failure.
  *
  * u64 bpf_get_current_pid_tgid(void)
- *     Return: current->tgid << 32 | current->pid
+ * 	Return
+ * 		A 64-bit integer containing the current tgid and pid, and
+ * 		created as such:
+ * 		*current_task*\ **->tgid << 32 \|**
+ * 		*current_task*\ **->pid**.
  *
  * u64 bpf_get_current_uid_gid(void)
- *     Return: current_gid << 32 | current_uid
- *
- * int bpf_get_current_comm(char *buf, int size_of_buf)
- *     stores current->comm into buf
- *     Return: 0 on success or negative error
- *
- * u32 bpf_get_cgroup_classid(skb)
- *     retrieve a proc's classid
- *     @skb: pointer to skb
- *     Return: classid if != 0
- *
- * int bpf_skb_vlan_push(skb, vlan_proto, vlan_tci)
- *     Return: 0 on success or negative error
- *
- * int bpf_skb_vlan_pop(skb)
- *     Return: 0 on success or negative error
- *
- * int bpf_skb_get_tunnel_key(skb, key, size, flags)
- * int bpf_skb_set_tunnel_key(skb, key, size, flags)
- *     retrieve or populate tunnel metadata
- *     @skb: pointer to skb
- *     @key: pointer to 'struct bpf_tunnel_key'
- *     @size: size of 'struct bpf_tunnel_key'
- *     @flags: room for future extensions
- *     Return: 0 on success or negative error
- *
- * u64 bpf_perf_event_read(map, flags)
- *     read perf event counter value
- *     @map: pointer to perf_event_array map
- *     @flags: index of event in the map or bitmask flags
- *     Return: value of perf event counter read or error code
- *
- * int bpf_redirect(ifindex, flags)
- *     redirect to another netdev
- *     @ifindex: ifindex of the net device
- *     @flags:
- *	  cls_bpf:
- *          bit 0 - if set, redirect to ingress instead of egress
- *          other bits - reserved
- *	  xdp_bpf:
- *	    all bits - reserved
- *     Return: cls_bpf: TC_ACT_REDIRECT on success or TC_ACT_SHOT on error
- *	       xdp_bfp: XDP_REDIRECT on success or XDP_ABORT on error
- * int bpf_redirect_map(map, key, flags)
- *     redirect to endpoint in map
- *     @map: pointer to dev map
- *     @key: index in map to lookup
- *     @flags: --
- *     Return: XDP_REDIRECT on success or XDP_ABORT on error
- *
- * u32 bpf_get_route_realm(skb)
- *     retrieve a dst's tclassid
- *     @skb: pointer to skb
- *     Return: realm if != 0
- *
- * int bpf_perf_event_output(ctx, map, flags, data, size)
- *     output perf raw sample
- *     @ctx: struct pt_regs*
- *     @map: pointer to perf_event_array map
- *     @flags: index of event in the map or bitmask flags
- *     @data: data on stack to be output as raw data
- *     @size: size of data
- *     Return: 0 on success or negative error
- *
- * int bpf_get_stackid(ctx, map, flags)
- *     walk user or kernel stack and return id
- *     @ctx: struct pt_regs*
- *     @map: pointer to stack_trace map
- *     @flags: bits 0-7 - numer of stack frames to skip
- *             bit 8 - collect user stack instead of kernel
- *             bit 9 - compare stacks by hash only
- *             bit 10 - if two different stacks hash into the same stackid
- *                      discard old
- *             other bits - reserved
- *     Return: >= 0 stackid on success or negative error
- *
- * s64 bpf_csum_diff(from, from_size, to, to_size, seed)
- *     calculate csum diff
- *     @from: raw from buffer
- *     @from_size: length of from buffer
- *     @to: raw to buffer
- *     @to_size: length of to buffer
- *     @seed: optional seed
- *     Return: csum result or negative error code
- *
- * int bpf_skb_get_tunnel_opt(skb, opt, size)
- *     retrieve tunnel options metadata
- *     @skb: pointer to skb
- *     @opt: pointer to raw tunnel option data
- *     @size: size of @opt
- *     Return: option size
- *
- * int bpf_skb_set_tunnel_opt(skb, opt, size)
- *     populate tunnel options metadata
- *     @skb: pointer to skb
- *     @opt: pointer to raw tunnel option data
- *     @size: size of @opt
- *     Return: 0 on success or negative error
- *
- * int bpf_skb_change_proto(skb, proto, flags)
- *     Change protocol of the skb. Currently supported is v4 -> v6,
- *     v6 -> v4 transitions. The helper will also resize the skb. eBPF
- *     program is expected to fill the new headers via skb_store_bytes
- *     and lX_csum_replace.
- *     @skb: pointer to skb
- *     @proto: new skb->protocol type
- *     @flags: reserved
- *     Return: 0 on success or negative error
- *
- * int bpf_skb_change_type(skb, type)
- *     Change packet type of skb.
- *     @skb: pointer to skb
- *     @type: new skb->pkt_type type
- *     Return: 0 on success or negative error
- *
- * int bpf_skb_under_cgroup(skb, map, index)
- *     Check cgroup2 membership of skb
- *     @skb: pointer to skb
- *     @map: pointer to bpf_map in BPF_MAP_TYPE_CGROUP_ARRAY type
- *     @index: index of the cgroup in the bpf_map
- *     Return:
- *       == 0 skb failed the cgroup2 descendant test
- *       == 1 skb succeeded the cgroup2 descendant test
- *        < 0 error
- *
- * u32 bpf_get_hash_recalc(skb)
- *     Retrieve and possibly recalculate skb->hash.
- *     @skb: pointer to skb
- *     Return: hash
+ * 	Return
+ * 		A 64-bit integer containing the current GID and UID, and
+ * 		created as such: *current_gid* **<< 32 \|** *current_uid*.
+ *
+ * int bpf_get_current_comm(char *buf, u32 size_of_buf)
+ * 	Description
+ * 		Copy the **comm** attribute of the current task into *buf* of
+ * 		*size_of_buf*. The **comm** attribute contains the name of
+ * 		the executable (excluding the path) for the current task. The
+ * 		*size_of_buf* must be strictly positive. On success, the
+ * 		helper makes sure that the *buf* is NUL-terminated. On failure,
+ * 		it is filled with zeroes.
+ * 	Return
+ * 		0 on success, or a negative error in case of failure.
+ *
+ * u32 bpf_get_cgroup_classid(struct sk_buff *skb)
+ * 	Description
+ * 		Retrieve the classid for the current task, i.e. for the net_cls
+ * 		cgroup to which *skb* belongs.
+ *
+ * 		This helper can be used on TC egress path, but not on ingress.
+ *
+ * 		The net_cls cgroup provides an interface to tag network packets
+ * 		based on a user-provided identifier for all traffic coming from
+ * 		the tasks belonging to the related cgroup. See also the related
+ * 		kernel documentation, available from the Linux sources in file
+ * 		*Documentation/cgroup-v1/net_cls.txt*.
+ *
+ * 		The Linux kernel has two versions for cgroups: there are
+ * 		cgroups v1 and cgroups v2. Both are available to users, who can
+ * 		use a mixture of them, but note that the net_cls cgroup is for
+ * 		cgroup v1 only. This makes it incompatible with BPF programs
+ * 		run on cgroups, which is a cgroup-v2-only feature (a socket can
+ * 		only hold data for one version of cgroups at a time).
+ *
+ * 		This helper is only available is the kernel was compiled with
+ * 		the **CONFIG_CGROUP_NET_CLASSID** configuration option set to
+ * 		"**y**" or to "**m**".
+ * 	Return
+ * 		The classid, or 0 for the default unconfigured classid.
+ *
+ * int bpf_skb_vlan_push(struct sk_buff *skb, __be16 vlan_proto, u16 vlan_tci)
+ * 	Description
+ * 		Push a *vlan_tci* (VLAN tag control information) of protocol
+ * 		*vlan_proto* to the packet associated to *skb*, then update
+ * 		the checksum. Note that if *vlan_proto* is different from
+ * 		**ETH_P_8021Q** and **ETH_P_8021AD**, it is considered to
+ * 		be **ETH_P_8021Q**.
+ *
+ * 		A call to this helper is susceptible to change the underlaying
+ * 		packet buffer. Therefore, at load time, all checks on pointers
+ * 		previously done by the verifier are invalidated and must be
+ * 		performed again, if the helper is used in combination with
+ * 		direct packet access.
+ * 	Return
+ * 		0 on success, or a negative error in case of failure.
+ *
+ * int bpf_skb_vlan_pop(struct sk_buff *skb)
+ * 	Description
+ * 		Pop a VLAN header from the packet associated to *skb*.
+ *
+ * 		A call to this helper is susceptible to change the underlaying
+ * 		packet buffer. Therefore, at load time, all checks on pointers
+ * 		previously done by the verifier are invalidated and must be
+ * 		performed again, if the helper is used in combination with
+ * 		direct packet access.
+ * 	Return
+ * 		0 on success, or a negative error in case of failure.
+ *
+ * int bpf_skb_get_tunnel_key(struct sk_buff *skb, struct bpf_tunnel_key *key, u32 size, u64 flags)
+ * 	Description
+ * 		Get tunnel metadata. This helper takes a pointer *key* to an
+ * 		empty **struct bpf_tunnel_key** of **size**, that will be
+ * 		filled with tunnel metadata for the packet associated to *skb*.
+ * 		The *flags* can be set to **BPF_F_TUNINFO_IPV6**, which
+ * 		indicates that the tunnel is based on IPv6 protocol instead of
+ * 		IPv4.
+ *
+ * 		The **struct bpf_tunnel_key** is an object that generalizes the
+ * 		principal parameters used by various tunneling protocols into a
+ * 		single struct. This way, it can be used to easily make a
+ * 		decision based on the contents of the encapsulation header,
+ * 		"summarized" in this struct. In particular, it holds the IP
+ * 		address of the remote end (IPv4 or IPv6, depending on the case)
+ * 		in *key*\ **->remote_ipv4** or *key*\ **->remote_ipv6**. Also,
+ * 		this struct exposes the *key*\ **->tunnel_id**, which is
+ * 		generally mapped to a VNI (Virtual Network Identifier), making
+ * 		it programmable together with the **bpf_skb_set_tunnel_key**\
+ * 		() helper.
+ *
+ * 		Let's imagine that the following code is part of a program
+ * 		attached to the TC ingress interface, on one end of a GRE
+ * 		tunnel, and is supposed to filter out all messages coming from
+ * 		remote ends with IPv4 address other than 10.0.0.1:
+ *
+ * 		::
+ *
+ * 			int ret;
+ * 			struct bpf_tunnel_key key = {};
+ * 			
+ * 			ret = bpf_skb_get_tunnel_key(skb, &key, sizeof(key), 0);
+ * 			if (ret < 0)
+ * 				return TC_ACT_SHOT;	// drop packet
+ * 			
+ * 			if (key.remote_ipv4 != 0x0a000001)
+ * 				return TC_ACT_SHOT;	// drop packet
+ * 			
+ * 			return TC_ACT_OK;		// accept packet
+ *
+ * 		This interface can also be used with all encapsulation devices
+ * 		that can operate in "collect metadata" mode: instead of having
+ * 		one network device per specific configuration, the "collect
+ * 		metadata" mode only requires a single device where the
+ * 		configuration can be extracted from this helper.
+ *
+ * 		This can be used together with various tunnels such as VXLan,
+ * 		Geneve, GRE or IP in IP (IPIP).
+ * 	Return
+ * 		0 on success, or a negative error in case of failure.
+ *
+ * int bpf_skb_set_tunnel_key(struct sk_buff *skb, struct bpf_tunnel_key *key, u32 size, u64 flags)
+ * 	Description
+ * 		Populate tunnel metadata for packet associated to *skb.* The
+ * 		tunnel metadata is set to the contents of *key*, of *size*. The
+ * 		*flags* can be set to a combination of the following values:
+ *
+ * 		**BPF_F_TUNINFO_IPV6**
+ * 			Indicate that the tunnel is based on IPv6 protocol
+ * 			instead of IPv4.
+ * 		**BPF_F_ZERO_CSUM_TX**
+ * 			For IPv4 packets, add a flag to tunnel metadata
+ * 			indicating that checksum computation should be skipped
+ * 			and checksum set to zeroes.
+ * 		**BPF_F_DONT_FRAGMENT**
+ * 			Add a flag to tunnel metadata indicating that the
+ * 			packet should not be fragmented.
+ * 		**BPF_F_SEQ_NUMBER**
+ * 			Add a flag to tunnel metadata indicating that a
+ * 			sequence number should be added to tunnel header before
+ * 			sending the packet. This flag was added for GRE
+ * 			encapsulation, but might be used with other protocols
+ * 			as well in the future.
+ *
+ * 		Here is a typical usage on the transmit path:
+ *
+ * 		::
+ *
+ * 			struct bpf_tunnel_key key;
+ * 			     populate key ...
+ * 			bpf_skb_set_tunnel_key(skb, &key, sizeof(key), 0);
+ * 			bpf_clone_redirect(skb, vxlan_dev_ifindex, 0);
+ *
+ * 		See also the description of the **bpf_skb_get_tunnel_key**\ ()
+ * 		helper for additional information.
+ * 	Return
+ * 		0 on success, or a negative error in case of failure.
+ *
+ * u64 bpf_perf_event_read(struct bpf_map *map, u64 flags)
+ * 	Description
+ * 		Read the value of a perf event counter. This helper relies on a
+ * 		*map* of type **BPF_MAP_TYPE_PERF_EVENT_ARRAY**. The nature of
+ * 		the perf event counter is selected when *map* is updated with
+ * 		perf event file descriptors. The *map* is an array whose size
+ * 		is the number of available CPUs, and each cell contains a value
+ * 		relative to one CPU. The value to retrieve is indicated by
+ * 		*flags*, that contains the index of the CPU to look up, masked
+ * 		with **BPF_F_INDEX_MASK**. Alternatively, *flags* can be set to
+ * 		**BPF_F_CURRENT_CPU** to indicate that the value for the
+ * 		current CPU should be retrieved.
+ *
+ * 		Note that before Linux 4.13, only hardware perf event can be
+ * 		retrieved.
+ *
+ * 		Also, be aware that the newer helper
+ * 		**bpf_perf_event_read_value**\ () is recommended over
+ * 		**bpf_perf_event_read*\ () in general. The latter has some ABI
+ * 		quirks where error and counter value are used as a return code
+ * 		(which is wrong to do since ranges may overlap). This issue is
+ * 		fixed with bpf_perf_event_read_value(), which at the same time
+ * 		provides more features over the **bpf_perf_event_read**\ ()
+ * 		interface. Please refer to the description of
+ * 		**bpf_perf_event_read_value**\ () for details.
+ * 	Return
+ * 		The value of the perf event counter read from the map, or a
+ * 		negative error code in case of failure.
+ *
+ * int bpf_redirect(u32 ifindex, u64 flags)
+ * 	Description
+ * 		Redirect the packet to another net device of index *ifindex*.
+ * 		This helper is somewhat similar to **bpf_clone_redirect**\
+ * 		(), except that the packet is not cloned, which provides
+ * 		increased performance.
+ *
+ * 		Except for XDP, both ingress and egress interfaces can be used
+ * 		for redirection. The **BPF_F_INGRESS** value in *flags* is used
+ * 		to make the distinction (ingress path is selected if the flag
+ * 		is present, egress path otherwise). Currently, XDP only
+ * 		supports redirection to the egress interface, and accepts no
+ * 		flag at all.
+ *
+ * 		The same effect can be attained with the more generic
+ * 		**bpf_redirect_map**\ (), which requires specific maps to be
+ * 		used but offers better performance.
+ * 	Return
+ * 		For XDP, the helper returns **XDP_REDIRECT** on success or
+ * 		**XDP_ABORTED** on error. For other program types, the values
+ * 		are **TC_ACT_REDIRECT** on success or **TC_ACT_SHOT** on
+ * 		error.
+ *
+ * u32 bpf_get_route_realm(struct sk_buff *skb)
+ * 	Description
+ * 		Retrieve the realm or the route, that is to say the
+ * 		**tclassid** field of the destination for the *skb*. The
+ * 		indentifier retrieved is a user-provided tag, similar to the
+ * 		one used with the net_cls cgroup (see description for
+ * 		**bpf_get_cgroup_classid**\ () helper), but here this tag is
+ * 		held by a route (a destination entry), not by a task.
+ *
+ * 		Retrieving this identifier works with the clsact TC egress hook
+ * 		(see also **tc-bpf(8)**), or alternatively on conventional
+ * 		classful egress qdiscs, but not on TC ingress path. In case of
+ * 		clsact TC egress hook, this has the advantage that, internally,
+ * 		the destination entry has not been dropped yet in the transmit
+ * 		path. Therefore, the destination entry does not need to be
+ * 		artificially held via **netif_keep_dst**\ () for a classful
+ * 		qdisc until the *skb* is freed.
+ *
+ * 		This helper is available only if the kernel was compiled with
+ * 		**CONFIG_IP_ROUTE_CLASSID** configuration option.
+ * 	Return
+ * 		The realm of the route for the packet associated to *skb*, or 0
+ * 		if none was found.
+ *
+ * int bpf_perf_event_output(struct pt_reg *ctx, struct bpf_map *map, u64 flags, void *data, u64 size)
+ * 	Description
+ * 		Write raw *data* blob into a special BPF perf event held by
+ * 		*map* of type **BPF_MAP_TYPE_PERF_EVENT_ARRAY**. This perf
+ * 		event must have the following attributes: **PERF_SAMPLE_RAW**
+ * 		as **sample_type**, **PERF_TYPE_SOFTWARE** as **type**, and
+ * 		**PERF_COUNT_SW_BPF_OUTPUT** as **config**.
+ *
+ * 		The *flags* are used to indicate the index in *map* for which
+ * 		the value must be put, masked with **BPF_F_INDEX_MASK**.
+ * 		Alternatively, *flags* can be set to **BPF_F_CURRENT_CPU**
+ * 		to indicate that the index of the current CPU core should be
+ * 		used.
+ *
+ * 		The value to write, of *size*, is passed through eBPF stack and
+ * 		pointed by *data*.
+ *
+ * 		The context of the program *ctx* needs also be passed to the
+ * 		helper.
+ *
+ * 		On user space, a program willing to read the values needs to
+ * 		call **perf_event_open**\ () on the perf event (either for
+ * 		one or for all CPUs) and to store the file descriptor into the
+ * 		*map*. This must be done before the eBPF program can send data
+ * 		into it. An example is available in file
+ * 		*samples/bpf/trace_output_user.c* in the Linux kernel source
+ * 		tree (the eBPF program counterpart is in
+ * 		*samples/bpf/trace_output_kern.c*).
+ *
+ * 		**bpf_perf_event_output**\ () achieves better performance
+ * 		than **bpf_trace_printk**\ () for sharing data with user
+ * 		space, and is much better suitable for streaming data from eBPF
+ * 		programs.
+ *
+ * 		Note that this helper is not restricted to tracing use cases
+ * 		and can be used with programs attached to TC or XDP as well,
+ * 		where it allows for passing data to user space listeners. Data
+ * 		can be:
+ *
+ * 		* Only custom structs,
+ * 		* Only the packet payload, or
+ * 		* A combination of both.
+ * 	Return
+ * 		0 on success, or a negative error in case of failure.
+ *
+ * int bpf_skb_load_bytes(const struct sk_buff *skb, u32 offset, void *to, u32 len)
+ * 	Description
+ * 		This helper was provided as an easy way to load data from a
+ * 		packet. It can be used to load *len* bytes from *offset* from
+ * 		the packet associated to *skb*, into the buffer pointed by
+ * 		*to*.
+ *
+ * 		Since Linux 4.7, usage of this helper has mostly been replaced
+ * 		by "direct packet access", enabling packet data to be
+ * 		manipulated with *skb*\ **->data** and *skb*\ **->data_end**
+ * 		pointing respectively to the first byte of packet data and to
+ * 		the byte after the last byte of packet data. However, it
+ * 		remains useful if one wishes to read large quantities of data
+ * 		at once from a packet into the eBPF stack.
+ * 	Return
+ * 		0 on success, or a negative error in case of failure.
+ *
+ * int bpf_get_stackid(struct pt_reg *ctx, struct bpf_map *map, u64 flags)
+ * 	Description
+ * 		Walk a user or a kernel stack and return its id. To achieve
+ * 		this, the helper needs *ctx*, which is a pointer to the context
+ * 		on which the tracing program is executed, and a pointer to a
+ * 		*map* of type **BPF_MAP_TYPE_STACK_TRACE**.
+ *
+ * 		The last argument, *flags*, holds the number of stack frames to
+ * 		skip (from 0 to 255), masked with
+ * 		**BPF_F_SKIP_FIELD_MASK**. The next bits can be used to set
+ * 		a combination of the following flags:
+ *
+ * 		**BPF_F_USER_STACK**
+ * 			Collect a user space stack instead of a kernel stack.
+ * 		**BPF_F_FAST_STACK_CMP**
+ * 			Compare stacks by hash only.
+ * 		**BPF_F_REUSE_STACKID**
+ * 			If two different stacks hash into the same *stackid*,
+ * 			discard the old one.
+ *
+ * 		The stack id retrieved is a 32 bit long integer handle which
+ * 		can be further combined with other data (including other stack
+ * 		ids) and used as a key into maps. This can be useful for
+ * 		generating a variety of graphs (such as flame graphs or off-cpu
+ * 		graphs).
+ *
+ * 		For walking a stack, this helper is an improvement over
+ * 		**bpf_probe_read**\ (), which can be used with unrolled loops
+ * 		but is not efficient and consumes a lot of eBPF instructions.
+ * 		Instead, **bpf_get_stackid**\ () can collect up to
+ * 		**PERF_MAX_STACK_DEPTH** both kernel and user frames. Note that
+ * 		this limit can be controlled with the **sysctl** program, and
+ * 		that it should be manually increased in order to profile long
+ * 		user stacks (such as stacks for Java programs). To do so, use:
+ *
+ * 		::
+ *
+ * 			# sysctl kernel.perf_event_max_stack=<new value>
+ *
+ * 	Return
+ * 		The positive or null stack id on success, or a negative error
+ * 		in case of failure.
+ *
+ * s64 bpf_csum_diff(__be32 *from, u32 from_size, __be32 *to, u32 to_size, __wsum seed)
+ * 	Description
+ * 		Compute a checksum difference, from the raw buffer pointed by
+ * 		*from*, of length *from_size* (that must be a multiple of 4),
+ * 		towards the raw buffer pointed by *to*, of size *to_size*
+ * 		(same remark). An optional *seed* can be added to the value
+ * 		(this can be cascaded, the seed may come from a previous call
+ * 		to the helper).
+ *
+ * 		This is flexible enough to be used in several ways:
+ *
+ * 		* With *from_size* == 0, *to_size* > 0 and *seed* set to
+ * 		  checksum, it can be used when pushing new data.
+ * 		* With *from_size* > 0, *to_size* == 0 and *seed* set to
+ * 		  checksum, it can be used when removing data from a packet.
+ * 		* With *from_size* > 0, *to_size* > 0 and *seed* set to 0, it
+ * 		  can be used to compute a diff. Note that *from_size* and
+ * 		  *to_size* do not need to be equal.
+ *
+ * 		This helper can be used in combination with
+ * 		**bpf_l3_csum_replace**\ () and **bpf_l4_csum_replace**\ (), to
+ * 		which one can feed in the difference computed with
+ * 		**bpf_csum_diff**\ ().
+ * 	Return
+ * 		The checksum result, or a negative error code in case of
+ * 		failure.
+ *
+ * int bpf_skb_get_tunnel_opt(struct sk_buff *skb, u8 *opt, u32 size)
+ * 	Description
+ * 		Retrieve tunnel options metadata for the packet associated to
+ * 		*skb*, and store the raw tunnel option data to the buffer *opt*
+ * 		of *size*.
+ *
+ * 		This helper can be used with encapsulation devices that can
+ * 		operate in "collect metadata" mode (please refer to the related
+ * 		note in the description of **bpf_skb_get_tunnel_key**\ () for
+ * 		more details). A particular example where this can be used is
+ * 		in combination with the Geneve encapsulation protocol, where it
+ * 		allows for pushing (with **bpf_skb_get_tunnel_opt**\ () helper)
+ * 		and retrieving arbitrary TLVs (Type-Length-Value headers) from
+ * 		the eBPF program. This allows for full customization of these
+ * 		headers.
+ * 	Return
+ * 		The size of the option data retrieved.
+ *
+ * int bpf_skb_set_tunnel_opt(struct sk_buff *skb, u8 *opt, u32 size)
+ * 	Description
+ * 		Set tunnel options metadata for the packet associated to *skb*
+ * 		to the option data contained in the raw buffer *opt* of *size*.
+ *
+ * 		See also the description of the **bpf_skb_get_tunnel_opt**\ ()
+ * 		helper for additional information.
+ * 	Return
+ * 		0 on success, or a negative error in case of failure.
+ *
+ * int bpf_skb_change_proto(struct sk_buff *skb, __be16 proto, u64 flags)
+ * 	Description
+ * 		Change the protocol of the *skb* to *proto*. Currently
+ * 		supported are transition from IPv4 to IPv6, and from IPv6 to
+ * 		IPv4. The helper takes care of the groundwork for the
+ * 		transition, including resizing the socket buffer. The eBPF
+ * 		program is expected to fill the new headers, if any, via
+ * 		**skb_store_bytes**\ () and to recompute the checksums with
+ * 		**bpf_l3_csum_replace**\ () and **bpf_l4_csum_replace**\
+ * 		(). The main case for this helper is to perform NAT64
+ * 		operations out of an eBPF program.
+ *
+ * 		Internally, the GSO type is marked as dodgy so that headers are
+ * 		checked and segments are recalculated by the GSO/GRO engine.
+ * 		The size for GSO target is adapted as well.
+ *
+ * 		All values for *flags* are reserved for future usage, and must
+ * 		be left at zero.
+ *
+ * 		A call to this helper is susceptible to change the underlaying
+ * 		packet buffer. Therefore, at load time, all checks on pointers
+ * 		previously done by the verifier are invalidated and must be
+ * 		performed again, if the helper is used in combination with
+ * 		direct packet access.
+ * 	Return
+ * 		0 on success, or a negative error in case of failure.
+ *
+ * int bpf_skb_change_type(struct sk_buff *skb, u32 type)
+ * 	Description
+ * 		Change the packet type for the packet associated to *skb*. This
+ * 		comes down to setting *skb*\ **->pkt_type** to *type*, except
+ * 		the eBPF program does not have a write access to *skb*\
+ * 		**->pkt_type** beside this helper. Using a helper here allows
+ * 		for graceful handling of errors.
+ *
+ * 		The major use case is to change incoming *skb*s to
+ * 		**PACKET_HOST** in a programmatic way instead of having to
+ * 		recirculate via **redirect**\ (..., **BPF_F_INGRESS**), for
+ * 		example.
+ *
+ * 		Note that *type* only allows certain values. At this time, they
+ * 		are:
+ *
+ * 		**PACKET_HOST**
+ * 			Packet is for us.
+ * 		**PACKET_BROADCAST**
+ * 			Send packet to all.
+ * 		**PACKET_MULTICAST**
+ * 			Send packet to group.
+ * 		**PACKET_OTHERHOST**
+ * 			Send packet to someone else.
+ * 	Return
+ * 		0 on success, or a negative error in case of failure.
+ *
+ * int bpf_skb_under_cgroup(struct sk_buff *skb, struct bpf_map *map, u32 index)
+ * 	Description
+ * 		Check whether *skb* is a descendant of the cgroup2 held by
+ * 		*map* of type **BPF_MAP_TYPE_CGROUP_ARRAY**, at *index*.
+ * 	Return
+ * 		The return value depends on the result of the test, and can be:
+ *
+ * 		* 0, if the *skb* failed the cgroup2 descendant test.
+ * 		* 1, if the *skb* succeeded the cgroup2 descendant test.
+ * 		* A negative error code, if an error occurred.
+ *
+ * u32 bpf_get_hash_recalc(struct sk_buff *skb)
+ * 	Description
+ * 		Retrieve the hash of the packet, *skb*\ **->hash**. If it is
+ * 		not set, in particular if the hash was cleared due to mangling,
+ * 		recompute this hash. Later accesses to the hash can be done
+ * 		directly with *skb*\ **->hash**.
+ *
+ * 		Calling **bpf_set_hash_invalid**\ (), changing a packet
+ * 		prototype with **bpf_skb_change_proto**\ (), or calling
+ * 		**bpf_skb_store_bytes**\ () with the
+ * 		**BPF_F_INVALIDATE_HASH** are actions susceptible to clear
+ * 		the hash and to trigger a new computation for the next call to
+ * 		**bpf_get_hash_recalc**\ ().
+ * 	Return
+ * 		The 32-bit hash.
  *
  * u64 bpf_get_current_task(void)
- *     Returns current task_struct
- *     Return: current
- *
- * int bpf_probe_write_user(void *dst, void *src, int len)
- *     safely attempt to write to a location
- *     @dst: destination address in userspace
- *     @src: source address on stack
- *     @len: number of bytes to copy
- *     Return: 0 on success or negative error
- *
- * int bpf_current_task_under_cgroup(map, index)
- *     Check cgroup2 membership of current task
- *     @map: pointer to bpf_map in BPF_MAP_TYPE_CGROUP_ARRAY type
- *     @index: index of the cgroup in the bpf_map
- *     Return:
- *       == 0 current failed the cgroup2 descendant test
- *       == 1 current succeeded the cgroup2 descendant test
- *        < 0 error
- *
- * int bpf_skb_change_tail(skb, len, flags)
- *     The helper will resize the skb to the given new size, to be used f.e.
- *     with control messages.
- *     @skb: pointer to skb
- *     @len: new skb length
- *     @flags: reserved
- *     Return: 0 on success or negative error
- *
- * int bpf_skb_pull_data(skb, len)
- *     The helper will pull in non-linear data in case the skb is non-linear
- *     and not all of len are part of the linear section. Only needed for
- *     read/write with direct packet access.
- *     @skb: pointer to skb
- *     @len: len to make read/writeable
- *     Return: 0 on success or negative error
- *
- * s64 bpf_csum_update(skb, csum)
- *     Adds csum into skb->csum in case of CHECKSUM_COMPLETE.
- *     @skb: pointer to skb
- *     @csum: csum to add
- *     Return: csum on success or negative error
- *
- * void bpf_set_hash_invalid(skb)
- *     Invalidate current skb->hash.
- *     @skb: pointer to skb
- *
- * int bpf_get_numa_node_id()
- *     Return: Id of current NUMA node.
- *
- * int bpf_skb_change_head()
- *     Grows headroom of skb and adjusts MAC header offset accordingly.
- *     Will extends/reallocae as required automatically.
- *     May change skb data pointer and will thus invalidate any check
- *     performed for direct packet access.
- *     @skb: pointer to skb
- *     @len: length of header to be pushed in front
- *     @flags: Flags (unused for now)
- *     Return: 0 on success or negative error
- *
- * int bpf_xdp_adjust_head(xdp_md, delta)
- *     Adjust the xdp_md.data by delta
- *     @xdp_md: pointer to xdp_md
- *     @delta: An positive/negative integer to be added to xdp_md.data
- *     Return: 0 on success or negative on error
+ * 	Return
+ * 		A pointer to the current task struct.
+ *
+ * int bpf_probe_write_user(void *dst, const void *src, u32 len)
+ * 	Description
+ * 		Attempt in a safe way to write *len* bytes from the buffer
+ * 		*src* to *dst* in memory. It only works for threads that are in
+ * 		user context, and *dst* must be a valid user space address.
+ *
+ * 		This helper should not be used to implement any kind of
+ * 		security mechanism because of TOC-TOU attacks, but rather to
+ * 		debug, divert, and manipulate execution of semi-cooperative
+ * 		processes.
+ *
+ * 		Keep in mind that this feature is meant for experiments, and it
+ * 		has a risk of crashing the system and running programs.
+ * 		Therefore, when an eBPF program using this helper is attached,
+ * 		a warning including PID and process name is printed to kernel
+ * 		logs.
+ * 	Return
+ * 		0 on success, or a negative error in case of failure.
+ *
+ * int bpf_current_task_under_cgroup(struct bpf_map *map, u32 index)
+ * 	Description
+ * 		Check whether the probe is being run is the context of a given
+ * 		subset of the cgroup2 hierarchy. The cgroup2 to test is held by
+ * 		*map* of type **BPF_MAP_TYPE_CGROUP_ARRAY**, at *index*.
+ * 	Return
+ * 		The return value depends on the result of the test, and can be:
+ *
+ * 		* 0, if the *skb* task belongs to the cgroup2.
+ * 		* 1, if the *skb* task does not belong to the cgroup2.
+ * 		* A negative error code, if an error occurred.
+ *
+ * int bpf_skb_change_tail(struct sk_buff *skb, u32 len, u64 flags)
+ * 	Description
+ * 		Resize (trim or grow) the packet associated to *skb* to the
+ * 		new *len*. The *flags* are reserved for future usage, and must
+ * 		be left at zero.
+ *
+ * 		The basic idea is that the helper performs the needed work to
+ * 		change the size of the packet, then the eBPF program rewrites
+ * 		the rest via helpers like **bpf_skb_store_bytes**\ (),
+ * 		**bpf_l3_csum_replace**\ (), **bpf_l3_csum_replace**\ ()
+ * 		and others. This helper is a slow path utility intended for
+ * 		replies with control messages. And because it is targeted for
+ * 		slow path, the helper itself can afford to be slow: it
+ * 		implicitly linearizes, unclones and drops offloads from the
+ * 		*skb*.
+ *
+ * 		A call to this helper is susceptible to change the underlaying
+ * 		packet buffer. Therefore, at load time, all checks on pointers
+ * 		previously done by the verifier are invalidated and must be
+ * 		performed again, if the helper is used in combination with
+ * 		direct packet access.
+ * 	Return
+ * 		0 on success, or a negative error in case of failure.
+ *
+ * int bpf_skb_pull_data(struct sk_buff *skb, u32 len)
+ * 	Description
+ * 		Pull in non-linear data in case the *skb* is non-linear and not
+ * 		all of *len* are part of the linear section. Make *len* bytes
+ * 		from *skb* readable and writable. If a zero value is passed for
+ * 		*len*, then the whole length of the *skb* is pulled.
+ *
+ * 		This helper is only needed for reading and writing with direct
+ * 		packet access.
+ *
+ * 		For direct packet access, testing that offsets to access
+ * 		are within packet boundaries (test on *skb*\ **->data_end**) is
+ * 		susceptible to fail if offsets are invalid, or if the requested
+ * 		data is in non-linear parts of the *skb*. On failure the
+ * 		program can just bail out, or in the case of a non-linear
+ * 		buffer, use a helper to make the data available. The
+ * 		**bpf_skb_load_bytes**\ () helper is a first solution to access
+ * 		the data. Another one consists in using **bpf_skb_pull_data**
+ * 		to pull in once the non-linear parts, then retesting and
+ * 		eventually access the data.
+ *
+ * 		At the same time, this also makes sure the *skb* is uncloned,
+ * 		which is a necessary condition for direct write. As this needs
+ * 		to be an invariant for the write part only, the verifier
+ * 		detects writes and adds a prologue that is calling
+ * 		**bpf_skb_pull_data()** to effectively unclone the *skb* from
+ * 		the very beginning in case it is indeed cloned.
+ *
+ * 		A call to this helper is susceptible to change the underlaying
+ * 		packet buffer. Therefore, at load time, all checks on pointers
+ * 		previously done by the verifier are invalidated and must be
+ * 		performed again, if the helper is used in combination with
+ * 		direct packet access.
+ * 	Return
+ * 		0 on success, or a negative error in case of failure.
+ *
+ * s64 bpf_csum_update(struct sk_buff *skb, __wsum csum)
+ * 	Description
+ * 		Add the checksum *csum* into *skb*\ **->csum** in case the
+ * 		driver has supplied a checksum for the entire packet into that
+ * 		field. Return an error otherwise. This helper is intended to be
+ * 		used in combination with **bpf_csum_diff**\ (), in particular
+ * 		when the checksum needs to be updated after data has been
+ * 		written into the packet through direct packet access.
+ * 	Return
+ * 		The checksum on success, or a negative error code in case of
+ * 		failure.
+ *
+ * void bpf_set_hash_invalid(struct sk_buff *skb)
+ * 	Description
+ * 		Invalidate the current *skb*\ **->hash**. It can be used after
+ * 		mangling on headers through direct packet access, in order to
+ * 		indicate that the hash is outdated and to trigger a
+ * 		recalculation the next time the kernel tries to access this
+ * 		hash or when the **bpf_get_hash_recalc**\ () helper is called.
+ *
+ * int bpf_get_numa_node_id(void)
+ * 	Description
+ * 		Return the id of the current NUMA node. The primary use case
+ * 		for this helper is the selection of sockets for the local NUMA
+ * 		node, when the program is attached to sockets using the
+ * 		**SO_ATTACH_REUSEPORT_EBPF** option (see also **socket(7)**),
+ * 		but the helper is also available to other eBPF program types,
+ * 		similarly to **bpf_get_smp_processor_id**\ ().
+ * 	Return
+ * 		The id of current NUMA node.
+ *
+ * int bpf_skb_change_head(struct sk_buff *skb, u32 len, u64 flags)
+ * 	Description
+ * 		Grows headroom of packet associated to *skb* and adjusts the
+ * 		offset of the MAC header accordingly, adding *len* bytes of
+ * 		space. It automatically extends and reallocates memory as
+ * 		required.
+ *
+ * 		This helper can be used on a layer 3 *skb* to push a MAC header
+ * 		for redirection into a layer 2 device.
+ *
+ * 		All values for *flags* are reserved for future usage, and must
+ * 		be left at zero.
+ *
+ * 		A call to this helper is susceptible to change the underlaying
+ * 		packet buffer. Therefore, at load time, all checks on pointers
+ * 		previously done by the verifier are invalidated and must be
+ * 		performed again, if the helper is used in combination with
+ * 		direct packet access.
+ * 	Return
+ * 		0 on success, or a negative error in case of failure.
+ *
+ * int bpf_xdp_adjust_head(struct xdp_buff *xdp_md, int delta)
+ * 	Description
+ * 		Adjust (move) *xdp_md*\ **->data** by *delta* bytes. Note that
+ * 		it is possible to use a negative value for *delta*. This helper
+ * 		can be used to prepare the packet for pushing or popping
+ * 		headers.
+ *
+ * 		A call to this helper is susceptible to change the underlaying
+ * 		packet buffer. Therefore, at load time, all checks on pointers
+ * 		previously done by the verifier are invalidated and must be
+ * 		performed again, if the helper is used in combination with
+ * 		direct packet access.
+ * 	Return
+ * 		0 on success, or a negative error in case of failure.
  *
  * int bpf_probe_read_str(void *dst, int size, const void *unsafe_ptr)
- *     Copy a NUL terminated string from unsafe address. In case the string
- *     length is smaller than size, the target is not padded with further NUL
- *     bytes. In case the string length is larger than size, just count-1
- *     bytes are copied and the last byte is set to NUL.
- *     @dst: destination address
- *     @size: maximum number of bytes to copy, including the trailing NUL
- *     @unsafe_ptr: unsafe address
- *     Return:
- *       > 0 length of the string including the trailing NUL on success
- *       < 0 error
- *
- * u64 bpf_get_socket_cookie(skb)
- *     Get the cookie for the socket stored inside sk_buff.
- *     @skb: pointer to skb
- *     Return: 8 Bytes non-decreasing number on success or 0 if the socket
- *     field is missing inside sk_buff
- *
- * u32 bpf_get_socket_uid(skb)
- *     Get the owner uid of the socket stored inside sk_buff.
- *     @skb: pointer to skb
- *     Return: uid of the socket owner on success or overflowuid if failed.
- *
- * u32 bpf_set_hash(skb, hash)
- *     Set full skb->hash.
- *     @skb: pointer to skb
- *     @hash: hash to set
- *
- * int bpf_setsockopt(bpf_socket, level, optname, optval, optlen)
- *     Calls setsockopt. Not all opts are available, only those with
- *     integer optvals plus TCP_CONGESTION.
- *     Supported levels: SOL_SOCKET and IPPROTO_TCP
- *     @bpf_socket: pointer to bpf_socket
- *     @level: SOL_SOCKET or IPPROTO_TCP
- *     @optname: option name
- *     @optval: pointer to option value
- *     @optlen: length of optval in bytes
- *     Return: 0 or negative error
- *
- * int bpf_getsockopt(bpf_socket, level, optname, optval, optlen)
- *     Calls getsockopt. Not all opts are available.
- *     Supported levels: IPPROTO_TCP
- *     @bpf_socket: pointer to bpf_socket
- *     @level: IPPROTO_TCP
- *     @optname: option name
- *     @optval: pointer to option value
- *     @optlen: length of optval in bytes
- *     Return: 0 or negative error
- *
- * int bpf_sock_ops_cb_flags_set(bpf_sock_ops, flags)
- *     Set callback flags for sock_ops
- *     @bpf_sock_ops: pointer to bpf_sock_ops_kern struct
- *     @flags: flags value
- *     Return: 0 for no error
- *             -EINVAL if there is no full tcp socket
- *             bits in flags that are not supported by current kernel
- *
- * int bpf_skb_adjust_room(skb, len_diff, mode, flags)
- *     Grow or shrink room in sk_buff.
- *     @skb: pointer to skb
- *     @len_diff: (signed) amount of room to grow/shrink
- *     @mode: operation mode (enum bpf_adj_room_mode)
- *     @flags: reserved for future use
- *     Return: 0 on success or negative error code
- *
- * int bpf_sk_redirect_map(map, key, flags)
- *     Redirect skb to a sock in map using key as a lookup key for the
- *     sock in map.
- *     @map: pointer to sockmap
- *     @key: key to lookup sock in map
- *     @flags: reserved for future use
- *     Return: SK_PASS
- *
- * int bpf_sock_map_update(skops, map, key, flags)
- *	@skops: pointer to bpf_sock_ops
- *	@map: pointer to sockmap to update
- *	@key: key to insert/update sock in map
- *	@flags: same flags as map update elem
- *
- * int bpf_xdp_adjust_meta(xdp_md, delta)
- *     Adjust the xdp_md.data_meta by delta
- *     @xdp_md: pointer to xdp_md
- *     @delta: An positive/negative integer to be added to xdp_md.data_meta
- *     Return: 0 on success or negative on error
- *
- * int bpf_perf_event_read_value(map, flags, buf, buf_size)
- *     read perf event counter value and perf event enabled/running time
- *     @map: pointer to perf_event_array map
- *     @flags: index of event in the map or bitmask flags
- *     @buf: buf to fill
- *     @buf_size: size of the buf
- *     Return: 0 on success or negative error code
- *
- * int bpf_perf_prog_read_value(ctx, buf, buf_size)
- *     read perf prog attached perf event counter and enabled/running time
- *     @ctx: pointer to ctx
- *     @buf: buf to fill
- *     @buf_size: size of the buf
- *     Return : 0 on success or negative error code
- *
- * int bpf_override_return(pt_regs, rc)
- *	@pt_regs: pointer to struct pt_regs
- *	@rc: the return value to set
- *
- * int bpf_msg_redirect_map(map, key, flags)
- *     Redirect msg to a sock in map using key as a lookup key for the
- *     sock in map.
- *     @map: pointer to sockmap
- *     @key: key to lookup sock in map
- *     @flags: reserved for future use
- *     Return: SK_PASS
- *
- * int bpf_bind(ctx, addr, addr_len)
- *     Bind socket to address. Only binding to IP is supported, no port can be
- *     set in addr.
- *     @ctx: pointer to context of type bpf_sock_addr
- *     @addr: pointer to struct sockaddr to bind socket to
- *     @addr_len: length of sockaddr structure
- *     Return: 0 on success or negative error code
- *
- * int bpf_xdp_adjust_tail(xdp_md, delta)
- *     Adjust the xdp_md.data_end by delta. Only shrinking of packet's
- *     size is supported.
- *     @xdp_md: pointer to xdp_md
- *     @delta: A negative integer to be added to xdp_md.data_end
- *     Return: 0 on success or negative on error
+ * 	Description
+ * 		Copy a NUL terminated string from an unsafe address
+ * 		*unsafe_ptr* to *dst*. The *size* should include the
+ * 		terminating NUL byte. In case the string length is smaller than
+ * 		*size*, the target is not padded with further NUL bytes. If the
+ * 		string length is larger than *size*, just *size*-1 bytes are
+ * 		copied and the last byte is set to NUL.
+ *
+ * 		On success, the length of the copied string is returned. This
+ * 		makes this helper useful in tracing programs for reading
+ * 		strings, and more importantly to get its length at runtime. See
+ * 		the following snippet:
+ *
+ * 		::
+ *
+ * 			SEC("kprobe/sys_open")
+ * 			void bpf_sys_open(struct pt_regs *ctx)
+ * 			{
+ * 			        char buf[PATHLEN]; // PATHLEN is defined to 256
+ * 			        int res = bpf_probe_read_str(buf, sizeof(buf),
+ * 				                             ctx->di);
+ *
+ * 				// Consume buf, for example push it to
+ * 				// userspace via bpf_perf_event_output(); we
+ * 				// can use res (the string length) as event
+ * 				// size, after checking its boundaries.
+ * 			}
+ *
+ * 		In comparison, using **bpf_probe_read()** helper here instead
+ * 		to read the string would require to estimate the length at
+ * 		compile time, and would often result in copying more memory
+ * 		than necessary.
+ *
+ * 		Another useful use case is when parsing individual process
+ * 		arguments or individual environment variables navigating
+ * 		*current*\ **->mm->arg_start** and *current*\
+ * 		**->mm->env_start**: using this helper and the return value,
+ * 		one can quickly iterate at the right offset of the memory area.
+ * 	Return
+ * 		On success, the strictly positive length of the string,
+ * 		including the trailing NUL character. On error, a negative
+ * 		value.
+ *
+ * u64 bpf_get_socket_cookie(struct sk_buff *skb)
+ * 	Description
+ * 		If the **struct sk_buff** pointed by *skb* has a known socket,
+ * 		retrieve the cookie (generated by the kernel) of this socket.
+ * 		If no cookie has been set yet, generate a new cookie. Once
+ * 		generated, the socket cookie remains stable for the life of the
+ * 		socket. This helper can be useful for monitoring per socket
+ * 		networking traffic statistics as it provides a unique socket
+ * 		identifier per namespace.
+ * 	Return
+ * 		A 8-byte long non-decreasing number on success, or 0 if the
+ * 		socket field is missing inside *skb*.
+ *
+ * u32 bpf_get_socket_uid(struct sk_buff *skb)
+ * 	Return
+ * 		The owner UID of the socket associated to *skb*. If the socket
+ * 		is **NULL**, or if it is not a full socket (i.e. if it is a
+ * 		time-wait or a request socket instead), **overflowuid** value
+ * 		is returned (note that **overflowuid** might also be the actual
+ * 		UID value for the socket).
+ *
+ * u32 bpf_set_hash(struct sk_buff *skb, u32 hash)
+ * 	Description
+ * 		Set the full hash for *skb* (set the field *skb*\ **->hash**)
+ * 		to value *hash*.
+ * 	Return
+ * 		0
+ *
+ * int bpf_setsockopt(struct bpf_sock_ops_kern *bpf_socket, int level, int optname, char *optval, int optlen)
+ * 	Description
+ * 		Emulate a call to **setsockopt()** on the socket associated to
+ * 		*bpf_socket*, which must be a full socket. The *level* at
+ * 		which the option resides and the name *optname* of the option
+ * 		must be specified, see **setsockopt(2)** for more information.
+ * 		The option value of length *optlen* is pointed by *optval*.
+ *
+ * 		This helper actually implements a subset of **setsockopt()**.
+ * 		It supports the following *level*\ s:
+ *
+ * 		* **SOL_SOCKET**, which supports the following *optname*\ s:
+ * 		  **SO_RCVBUF**, **SO_SNDBUF**, **SO_MAX_PACING_RATE**,
+ * 		  **SO_PRIORITY**, **SO_RCVLOWAT**, **SO_MARK**.
+ * 		* **IPPROTO_TCP**, which supports the following *optname*\ s:
+ * 		  **TCP_CONGESTION**, **TCP_BPF_IW**,
+ * 		  **TCP_BPF_SNDCWND_CLAMP**.
+ * 		* **IPPROTO_IP**, which supports *optname* **IP_TOS**.
+ * 		* **IPPROTO_IPV6**, which supports *optname* **IPV6_TCLASS**.
+ * 	Return
+ * 		0 on success, or a negative error in case of failure.
+ *
+ * int bpf_skb_adjust_room(struct sk_buff *skb, u32 len_diff, u32 mode, u64 flags)
+ * 	Description
+ * 		Grow or shrink the room for data in the packet associated to
+ * 		*skb* by *len_diff*, and according to the selected *mode*.
+ *
+ * 		There is a single supported mode at this time:
+ *
+ * 		* **BPF_ADJ_ROOM_NET**: Adjust room at the network layer
+ * 		  (room space is added or removed below the layer 3 header).
+ *
+ * 		All values for *flags* are reserved for future usage, and must
+ * 		be left at zero.
+ *
+ * 		A call to this helper is susceptible to change the underlaying
+ * 		packet buffer. Therefore, at load time, all checks on pointers
+ * 		previously done by the verifier are invalidated and must be
+ * 		performed again, if the helper is used in combination with
+ * 		direct packet access.
+ * 	Return
+ * 		0 on success, or a negative error in case of failure.
+ *
+ * int bpf_redirect_map(struct bpf_map *map, u32 key, u64 flags)
+ * 	Description
+ * 		Redirect the packet to the endpoint referenced by *map* at
+ * 		index *key*. Depending on its type, this *map* can contain
+ * 		references to net devices (for forwarding packets through other
+ * 		ports), or to CPUs (for redirecting XDP frames to another CPU;
+ * 		but this is only implemented for native XDP (with driver
+ * 		support) as of this writing).
+ *
+ * 		All values for *flags* are reserved for future usage, and must
+ * 		be left at zero.
+ *
+ * 		When used to redirect packets to net devices, this helper
+ * 		provides a high performance increase over **bpf_redirect**\ ().
+ * 		This is due to various implementation details of the underlying
+ * 		mechanisms, one of which is the fact that **bpf_redirect_map**\
+ * 		() tries to send packet as a "bulk" to the device.
+ * 	Return
+ * 		**XDP_REDIRECT** on success, or **XDP_ABORTED** on error.
+ *
+ * int bpf_sk_redirect_map(struct bpf_map *map, u32 key, u64 flags)
+ * 	Description
+ * 		Redirect the packet to the socket referenced by *map* (of type
+ * 		**BPF_MAP_TYPE_SOCKMAP**) at index *key*. Both ingress and
+ * 		egress interfaces can be used for redirection. The
+ * 		**BPF_F_INGRESS** value in *flags* is used to make the
+ * 		distinction (ingress path is selected if the flag is present,
+ * 		egress path otherwise). This is the only flag supported for now.
+ * 	Return
+ * 		**SK_PASS** on success, or **SK_DROP** on error.
+ *
+ * int bpf_sock_map_update(struct bpf_sock_ops_kern *skops, struct bpf_map *map, void *key, u64 flags)
+ * 	Description
+ * 		Add an entry to, or update a *map* referencing sockets. The
+ * 		*skops* is used as a new value for the entry associated to
+ * 		*key*. *flags* is one of:
+ *
+ * 		**BPF_NOEXIST**
+ * 			The entry for *key* must not exist in the map.
+ * 		**BPF_EXIST**
+ * 			The entry for *key* must already exist in the map.
+ * 		**BPF_ANY**
+ * 			No condition on the existence of the entry for *key*.
+ *
+ * 		If the *map* has eBPF programs (parser and verdict), those will
+ * 		be inherited by the socket being added. If the socket is
+ * 		already attached to eBPF programs, this results in an error.
+ * 	Return
+ * 		0 on success, or a negative error in case of failure.
+ *
+ * int bpf_xdp_adjust_meta(struct xdp_buff *xdp_md, int delta)
+ * 	Description
+ * 		Adjust the address pointed by *xdp_md*\ **->data_meta** by
+ * 		*delta* (which can be positive or negative). Note that this
+ * 		operation modifies the address stored in *xdp_md*\ **->data**,
+ * 		so the latter must be loaded only after the helper has been
+ * 		called.
+ *
+ * 		The use of *xdp_md*\ **->data_meta** is optional and programs
+ * 		are not required to use it. The rationale is that when the
+ * 		packet is processed with XDP (e.g. as DoS filter), it is
+ * 		possible to push further meta data along with it before passing
+ * 		to the stack, and to give the guarantee that an ingress eBPF
+ * 		program attached as a TC classifier on the same device can pick
+ * 		this up for further post-processing. Since TC works with socket
+ * 		buffers, it remains possible to set from XDP the **mark** or
+ * 		**priority** pointers, or other pointers for the socket buffer.
+ * 		Having this scratch space generic and programmable allows for
+ * 		more flexibility as the user is free to store whatever meta
+ * 		data they need.
+ *
+ * 		A call to this helper is susceptible to change the underlaying
+ * 		packet buffer. Therefore, at load time, all checks on pointers
+ * 		previously done by the verifier are invalidated and must be
+ * 		performed again, if the helper is used in combination with
+ * 		direct packet access.
+ * 	Return
+ * 		0 on success, or a negative error in case of failure.
+ *
+ * int bpf_perf_event_read_value(struct bpf_map *map, u64 flags, struct bpf_perf_event_value *buf, u32 buf_size)
+ * 	Description
+ * 		Read the value of a perf event counter, and store it into *buf*
+ * 		of size *buf_size*. This helper relies on a *map* of type
+ * 		**BPF_MAP_TYPE_PERF_EVENT_ARRAY**. The nature of the perf event
+ * 		counter is selected when *map* is updated with perf event file
+ * 		descriptors. The *map* is an array whose size is the number of
+ * 		available CPUs, and each cell contains a value relative to one
+ * 		CPU. The value to retrieve is indicated by *flags*, that
+ * 		contains the index of the CPU to look up, masked with
+ * 		**BPF_F_INDEX_MASK**. Alternatively, *flags* can be set to
+ * 		**BPF_F_CURRENT_CPU** to indicate that the value for the
+ * 		current CPU should be retrieved.
+ *
+ * 		This helper behaves in a way close to
+ * 		**bpf_perf_event_read**\ () helper, save that instead of
+ * 		just returning the value observed, it fills the *buf*
+ * 		structure. This allows for additional data to be retrieved: in
+ * 		particular, the enabled and running times (in *buf*\
+ * 		**->enabled** and *buf*\ **->running**, respectively) are
+ * 		copied. In general, **bpf_perf_event_read_value**\ () is
+ * 		recommended over **bpf_perf_event_read**\ (), which has some
+ * 		ABI issues and provides fewer functionalities.
+ *
+ * 		These values are interesting, because hardware PMU (Performance
+ * 		Monitoring Unit) counters are limited resources. When there are
+ * 		more PMU based perf events opened than available counters,
+ * 		kernel will multiplex these events so each event gets certain
+ * 		percentage (but not all) of the PMU time. In case that
+ * 		multiplexing happens, the number of samples or counter value
+ * 		will not reflect the case compared to when no multiplexing
+ * 		occurs. This makes comparison between different runs difficult.
+ * 		Typically, the counter value should be normalized before
+ * 		comparing to other experiments. The usual normalization is done
+ * 		as follows.
+ *
+ * 		::
+ *
+ * 			normalized_counter = counter * t_enabled / t_running
+ *
+ * 		Where t_enabled is the time enabled for event and t_running is
+ * 		the time running for event since last normalization. The
+ * 		enabled and running times are accumulated since the perf event
+ * 		open. To achieve scaling factor between two invocations of an
+ * 		eBPF program, users can can use CPU id as the key (which is
+ * 		typical for perf array usage model) to remember the previous
+ * 		value and do the calculation inside the eBPF program.
+ * 	Return
+ * 		0 on success, or a negative error in case of failure.
+ *
+ * int bpf_perf_prog_read_value(struct bpf_perf_event_data_kern *ctx, struct bpf_perf_event_value *buf, u32 buf_size)
+ * 	Description
+ * 		For en eBPF program attached to a perf event, retrieve the
+ * 		value of the event counter associated to *ctx* and store it in
+ * 		the structure pointed by *buf* and of size *buf_size*. Enabled
+ * 		and running times are also stored in the structure (see
+ * 		description of helper **bpf_perf_event_read_value**\ () for
+ * 		more details).
+ * 	Return
+ * 		0 on success, or a negative error in case of failure.
+ *
+ * int bpf_getsockopt(struct bpf_sock_ops_kern *bpf_socket, int level, int optname, char *optval, int optlen)
+ * 	Description
+ * 		Emulate a call to **getsockopt()** on the socket associated to
+ * 		*bpf_socket*, which must be a full socket. The *level* at
+ * 		which the option resides and the name *optname* of the option
+ * 		must be specified, see **getsockopt(2)** for more information.
+ * 		The retrieved value is stored in the structure pointed by
+ * 		*opval* and of length *optlen*.
+ *
+ * 		This helper actually implements a subset of **getsockopt()**.
+ * 		It supports the following *level*\ s:
+ *
+ * 		* **IPPROTO_TCP**, which supports *optname*
+ * 		  **TCP_CONGESTION**.
+ * 		* **IPPROTO_IP**, which supports *optname* **IP_TOS**.
+ * 		* **IPPROTO_IPV6**, which supports *optname* **IPV6_TCLASS**.
+ * 	Return
+ * 		0 on success, or a negative error in case of failure.
+ *
+ * int bpf_override_return(struct pt_reg *regs, u64 rc)
+ * 	Description
+ * 		Used for error injection, this helper uses kprobes to override
+ * 		the return value of the probed function, and to set it to *rc*.
+ * 		The first argument is the context *regs* on which the kprobe
+ * 		works.
+ *
+ * 		This helper works by setting setting the PC (program counter)
+ * 		to an override function which is run in place of the original
+ * 		probed function. This means the probed function is not run at
+ * 		all. The replacement function just returns with the required
+ * 		value.
+ *
+ * 		This helper has security implications, and thus is subject to
+ * 		restrictions. It is only available if the kernel was compiled
+ * 		with the **CONFIG_BPF_KPROBE_OVERRIDE** configuration
+ * 		option, and in this case it only works on functions tagged with
+ * 		**ALLOW_ERROR_INJECTION** in the kernel code.
+ *
+ * 		Also, the helper is only available for the architectures having
+ * 		the CONFIG_FUNCTION_ERROR_INJECTION option. As of this writing,
+ * 		x86 architecture is the only one to support this feature.
+ * 	Return
+ * 		0
+ *
+ * int bpf_sock_ops_cb_flags_set(struct bpf_sock_ops_kern *bpf_sock, int argval)
+ * 	Description
+ * 		Attempt to set the value of the **bpf_sock_ops_cb_flags** field
+ * 		for the full TCP socket associated to *bpf_sock_ops* to
+ * 		*argval*.
+ *
+ * 		The primary use of this field is to determine if there should
+ * 		be calls to eBPF programs of type
+ * 		**BPF_PROG_TYPE_SOCK_OPS** at various points in the TCP
+ * 		code. A program of the same type can change its value, per
+ * 		connection and as necessary, when the connection is
+ * 		established. This field is directly accessible for reading, but
+ * 		this helper must be used for updates in order to return an
+ * 		error if an eBPF program tries to set a callback that is not
+ * 		supported in the current kernel.
+ *
+ * 		The supported callback values that *argval* can combine are:
+ *
+ * 		* **BPF_SOCK_OPS_RTO_CB_FLAG** (retransmission time out)
+ * 		* **BPF_SOCK_OPS_RETRANS_CB_FLAG** (retransmission)
+ * 		* **BPF_SOCK_OPS_STATE_CB_FLAG** (TCP state change)
+ *
+ * 		Here are some examples of where one could call such eBPF
+ * 		program:
+ *
+ * 		* When RTO fires.
+ * 		* When a packet is retransmitted.
+ * 		* When the connection terminates.
+ * 		* When a packet is sent.
+ * 		* When a packet is received.
+ * 	Return
+ * 		Code **-EINVAL** if the socket is not a full TCP socket;
+ * 		otherwise, a positive number containing the bits that could not
+ * 		be set is returned (which comes down to 0 if all bits were set
+ * 		as required).
+ *
+ * int bpf_msg_redirect_map(struct sk_msg_buff *msg, struct bpf_map *map, u32 key, u64 flags)
+ * 	Description
+ * 		This helper is used in programs implementing policies at the
+ * 		socket level. If the message *msg* is allowed to pass (i.e. if
+ * 		the verdict eBPF program returns **SK_PASS**), redirect it to
+ * 		the socket referenced by *map* (of type
+ * 		**BPF_MAP_TYPE_SOCKMAP**) at index *key*. Both ingress and
+ * 		egress interfaces can be used for redirection. The
+ * 		**BPF_F_INGRESS** value in *flags* is used to make the
+ * 		distinction (ingress path is selected if the flag is present,
+ * 		egress path otherwise). This is the only flag supported for now.
+ * 	Return
+ * 		**SK_PASS** on success, or **SK_DROP** on error.
+ *
+ * int bpf_msg_apply_bytes(struct sk_msg_buff *msg, u32 bytes)
+ * 	Description
+ * 		For socket policies, apply the verdict of the eBPF program to
+ * 		the next *bytes* (number of bytes) of message *msg*.
+ *
+ * 		For example, this helper can be used in the following cases:
+ *
+ * 		* A single **sendmsg**\ () or **sendfile**\ () system call
+ * 		  contains multiple logical messages that the eBPF program is
+ * 		  supposed to read and for which it should apply a verdict.
+ * 		* An eBPF program only cares to read the first *bytes* of a
+ * 		  *msg*. If the message has a large payload, then setting up
+ * 		  and calling the eBPF program repeatedly for all bytes, even
+ * 		  though the verdict is already known, would create unnecessary
+ * 		  overhead.
+ *
+ * 		When called from within an eBPF program, the helper sets a
+ * 		counter internal to the BPF infrastructure, that is used to
+ * 		apply the last verdict to the next *bytes*. If *bytes* is
+ * 		smaller than the current data being processed from a
+ * 		**sendmsg**\ () or **sendfile**\ () system call, the first
+ * 		*bytes* will be sent and the eBPF program will be re-run with
+ * 		the pointer for start of data pointing to byte number *bytes*
+ * 		**+ 1**. If *bytes* is larger than the current data being
+ * 		processed, then the eBPF verdict will be applied to multiple
+ * 		**sendmsg**\ () or **sendfile**\ () calls until *bytes* are
+ * 		consumed.
+ *
+ * 		Note that if a socket closes with the internal counter holding
+ * 		a non-zero value, this is not a problem because data is not
+ * 		being buffered for *bytes* and is sent as it is received.
+ * 	Return
+ * 		0
+ *
+ * int bpf_msg_cork_bytes(struct sk_msg_buff *msg, u32 bytes)
+ * 	Description
+ * 		For socket policies, prevent the execution of the verdict eBPF
+ * 		program for message *msg* until *bytes* (byte number) have been
+ * 		accumulated.
+ *
+ * 		This can be used when one needs a specific number of bytes
+ * 		before a verdict can be assigned, even if the data spans
+ * 		multiple **sendmsg**\ () or **sendfile**\ () calls. The extreme
+ * 		case would be a user calling **sendmsg**\ () repeatedly with
+ * 		1-byte long message segments. Obviously, this is bad for
+ * 		performance, but it is still valid. If the eBPF program needs
+ * 		*bytes* bytes to validate a header, this helper can be used to
+ * 		prevent the eBPF program to be called again until *bytes* have
+ * 		been accumulated.
+ * 	Return
+ * 		0
+ *
+ * int bpf_msg_pull_data(struct sk_msg_buff *msg, u32 start, u32 end, u64 flags)
+ * 	Description
+ * 		For socket policies, pull in non-linear data from user space
+ * 		for *msg* and set pointers *msg*\ **->data** and *msg*\
+ * 		**->data_end** to *start* and *end* bytes offsets into *msg*,
+ * 		respectively.
+ *
+ * 		If a program of type **BPF_PROG_TYPE_SK_MSG** is run on a
+ * 		*msg* it can only parse data that the (**data**, **data_end**)
+ * 		pointers have already consumed. For **sendmsg**\ () hooks this
+ * 		is likely the first scatterlist element. But for calls relying
+ * 		on the **sendpage** handler (e.g. **sendfile**\ ()) this will
+ * 		be the range (**0**, **0**) because the data is shared with
+ * 		user space and by default the objective is to avoid allowing
+ * 		user space to modify data while (or after) eBPF verdict is
+ * 		being decided. This helper can be used to pull in data and to
+ * 		set the start and end pointer to given values. Data will be
+ * 		copied if necessary (i.e. if data was not linear and if start
+ * 		and end pointers do not point to the same chunk).
+ *
+ * 		A call to this helper is susceptible to change the underlaying
+ * 		packet buffer. Therefore, at load time, all checks on pointers
+ * 		previously done by the verifier are invalidated and must be
+ * 		performed again, if the helper is used in combination with
+ * 		direct packet access.
+ *
+ * 		All values for *flags* are reserved for future usage, and must
+ * 		be left at zero.
+ * 	Return
+ * 		0 on success, or a negative error in case of failure.
+ *
+ * int bpf_bind(struct bpf_sock_addr_kern *ctx, struct sockaddr *addr, int addr_len)
+ * 	Description
+ * 		Bind the socket associated to *ctx* to the address pointed by
+ * 		*addr*, of length *addr_len*. This allows for making outgoing
+ * 		connection from the desired IP address, which can be useful for
+ * 		example when all processes inside a cgroup should use one
+ * 		single IP address on a host that has multiple IP configured.
+ *
+ * 		This helper works for IPv4 and IPv6, TCP and UDP sockets. The
+ * 		domain (*addr*\ **->sa_family**) must be **AF_INET** (or
+ * 		**AF_INET6**). Looking for a free port to bind to can be
+ * 		expensive, therefore binding to port is not permitted by the
+ * 		helper: *addr*\ **->sin_port** (or **sin6_port**, respectively)
+ * 		must be set to zero.
+ * 	Return
+ * 		0 on success, or a negative error in case of failure.
+ *
+ * int bpf_xdp_adjust_tail(struct xdp_buff *xdp_md, int delta)
+ * 	Description
+ * 		Adjust (move) *xdp_md*\ **->data_end** by *delta* bytes. It is
+ * 		only possible to shrink the packet as of this writing,
+ * 		therefore *delta* must be a negative integer.
+ *
+ * 		A call to this helper is susceptible to change the underlaying
+ * 		packet buffer. Therefore, at load time, all checks on pointers
+ * 		previously done by the verifier are invalidated and must be
+ * 		performed again, if the helper is used in combination with
+ * 		direct packet access.
+ * 	Return
+ * 		0 on success, or a negative error in case of failure.
+ *
+ * int bpf_skb_get_xfrm_state(struct sk_buff *skb, u32 index, struct bpf_xfrm_state *xfrm_state, u32 size, u64 flags)
+ * 	Description
+ * 		Retrieve the XFRM state (IP transform framework, see also
+ * 		**ip-xfrm(8)**) at *index* in XFRM "security path" for *skb*.
+ *
+ * 		The retrieved value is stored in the **struct bpf_xfrm_state**
+ * 		pointed by *xfrm_state* and of length *size*.
+ *
+ * 		All values for *flags* are reserved for future usage, and must
+ * 		be left at zero.
+ *
+ * 		This helper is available only if the kernel was compiled with
+ * 		**CONFIG_XFRM** configuration option.
+ * 	Return
+ * 		0 on success, or a negative error in case of failure.
  */
 #define __BPF_FUNC_MAPPER(FN)		\
 	FN(unspec),			\
@@ -841,7 +1834,8 @@ union bpf_attr {
 	FN(msg_cork_bytes),		\
 	FN(msg_pull_data),		\
 	FN(bind),			\
-	FN(xdp_adjust_tail),
+	FN(xdp_adjust_tail),		\
+	FN(skb_get_xfrm_state),
 
 /* integer value in 'imm' field of BPF_CALL instruction selects which helper
  * function eBPF program intends to call
@@ -947,6 +1941,19 @@ struct bpf_tunnel_key {
 	__u32 tunnel_label;
 };
 
+/* user accessible mirror of in-kernel xfrm_state.
+ * new fields can only be added to the end of this structure
+ */
+struct bpf_xfrm_state {
+	__u32 reqid;
+	__u32 spi;	/* Stored in network byte order */
+	__u16 family;
+	union {
+		__u32 remote_ipv4;	/* Stored in network byte order */
+		__u32 remote_ipv6[4];	/* Stored in network byte order */
+	};
+};
+
 /* Generic BPF return codes which all BPF program types may support.
  * The values are binary compatible with their TC_ACT_* counter-part to
  * provide backwards compatibility with existing SCHED_CLS and SCHED_ACT
@@ -1037,6 +2044,7 @@ struct bpf_prog_info {
 	__aligned_u64 map_ids;
 	char name[BPF_OBJ_NAME_LEN];
 	__u32 ifindex;
+	__u32 gpl_compatible:1;
 	__u64 netns_dev;
 	__u64 netns_ino;
 } __attribute__((aligned(8)));
diff --git a/tools/include/uapi/linux/btf.h b/tools/include/uapi/linux/btf.h
index 74a30b1090df..bcb56ee47014 100644
--- a/tools/include/uapi/linux/btf.h
+++ b/tools/include/uapi/linux/btf.h
@@ -6,9 +6,7 @@
 #include <linux/types.h>
 
 #define BTF_MAGIC	0xeB9F
-#define BTF_MAGIC_SWAP	0x9FeB
 #define BTF_VERSION	1
-#define BTF_FLAGS_COMPR	0x01
 
 struct btf_header {
 	__u16	magic;
@@ -43,7 +41,7 @@ struct btf_header {
 #define BTF_STR_OFFSET(ref)	((ref) & BTF_MAX_NAME_OFFSET)
 
 struct btf_type {
-	__u32 name;
+	__u32 name_off;
 	/* "info" bits arrangement
 	 * bits  0-15: vlen (e.g. # of struct's members)
 	 * bits 16-23: unused
@@ -105,7 +103,7 @@ struct btf_type {
  * info in "struct btf_type").
  */
 struct btf_enum {
-	__u32	name;
+	__u32	name_off;
 	__s32	val;
 };
 
@@ -122,7 +120,7 @@ struct btf_array {
  * "struct btf_type").
  */
 struct btf_member {
-	__u32	name;
+	__u32	name_off;
 	__u32	type;
 	__u32	offset;	/* offset in bits */
 };
diff --git a/tools/lib/bpf/btf.c b/tools/lib/bpf/btf.c
index 58b6255abc7a..2bac710e3194 100644
--- a/tools/lib/bpf/btf.c
+++ b/tools/lib/bpf/btf.c
@@ -281,7 +281,7 @@ int32_t btf__find_by_name(const struct btf *btf, const char *type_name)
 
 	for (i = 1; i <= btf->nr_types; i++) {
 		const struct btf_type *t = btf->types[i];
-		const char *name = btf_name_by_offset(btf, t->name);
+		const char *name = btf_name_by_offset(btf, t->name_off);
 
 		if (name && !strcmp(type_name, name))
 			return i;
diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c
index 6513e0b08795..7bcdca13083a 100644
--- a/tools/lib/bpf/libbpf.c
+++ b/tools/lib/bpf/libbpf.c
@@ -1961,8 +1961,8 @@ BPF_PROG_TYPE_FNS(raw_tracepoint, BPF_PROG_TYPE_RAW_TRACEPOINT);
 BPF_PROG_TYPE_FNS(xdp, BPF_PROG_TYPE_XDP);
 BPF_PROG_TYPE_FNS(perf_event, BPF_PROG_TYPE_PERF_EVENT);
 
-static void bpf_program__set_expected_attach_type(struct bpf_program *prog,
-						 enum bpf_attach_type type)
+void bpf_program__set_expected_attach_type(struct bpf_program *prog,
+					   enum bpf_attach_type type)
 {
 	prog->expected_attach_type = type;
 }
diff --git a/tools/lib/bpf/libbpf.h b/tools/lib/bpf/libbpf.h
index d6ac4fa6f472..197f9ce2248c 100644
--- a/tools/lib/bpf/libbpf.h
+++ b/tools/lib/bpf/libbpf.h
@@ -193,6 +193,8 @@ int bpf_program__set_sched_act(struct bpf_program *prog);
 int bpf_program__set_xdp(struct bpf_program *prog);
 int bpf_program__set_perf_event(struct bpf_program *prog);
 void bpf_program__set_type(struct bpf_program *prog, enum bpf_prog_type type);
+void bpf_program__set_expected_attach_type(struct bpf_program *prog,
+					   enum bpf_attach_type type);
 
 bool bpf_program__is_socket_filter(struct bpf_program *prog);
 bool bpf_program__is_tracepoint(struct bpf_program *prog);
diff --git a/tools/testing/selftests/bpf/.gitignore b/tools/testing/selftests/bpf/.gitignore
index 5e1ab2f0eb79..3e3b3ced3f7c 100644
--- a/tools/testing/selftests/bpf/.gitignore
+++ b/tools/testing/selftests/bpf/.gitignore
@@ -15,3 +15,4 @@ test_libbpf_open
 test_sock
 test_sock_addr
 urandom_read
+test_btf
diff --git a/tools/testing/selftests/bpf/Makefile b/tools/testing/selftests/bpf/Makefile
index 0b72cc7596f1..b64a7a39cbc8 100644
--- a/tools/testing/selftests/bpf/Makefile
+++ b/tools/testing/selftests/bpf/Makefile
@@ -24,7 +24,7 @@ urandom_read: urandom_read.c
 # Order correspond to 'make run_tests' order
 TEST_GEN_PROGS = test_verifier test_tag test_maps test_lru_map test_lpm_map test_progs \
 	test_align test_verifier_log test_dev_cgroup test_tcpbpf_user \
-	test_sock test_sock_addr test_btf
+	test_sock test_btf test_sockmap
 
 TEST_GEN_FILES = test_pkt_access.o test_xdp.o test_l4lb.o test_tcp_estats.o test_obj_id.o \
 	test_pkt_md_access.o test_xdp_redirect.o test_xdp_meta.o sockmap_parse_prog.o     \
@@ -32,7 +32,7 @@ TEST_GEN_FILES = test_pkt_access.o test_xdp.o test_l4lb.o test_tcp_estats.o test
 	test_l4lb_noinline.o test_xdp_noinline.o test_stacktrace_map.o \
 	sample_map_ret0.o test_tcpbpf_kern.o test_stacktrace_build_id.o \
 	sockmap_tcp_msg_prog.o connect4_prog.o connect6_prog.o test_adjust_tail.o \
-	test_btf_haskv.o test_btf_nokv.o
+	test_btf_haskv.o test_btf_nokv.o test_sockmap_kern.o test_tunnel_kern.o
 
 # Order correspond to 'make run_tests' order
 TEST_PROGS := test_kmod.sh \
@@ -40,10 +40,11 @@ TEST_PROGS := test_kmod.sh \
 	test_xdp_redirect.sh \
 	test_xdp_meta.sh \
 	test_offload.py \
-	test_sock_addr.sh
+	test_sock_addr.sh \
+	test_tunnel.sh
 
 # Compile but not part of 'make run_tests'
-TEST_GEN_PROGS_EXTENDED = test_libbpf_open
+TEST_GEN_PROGS_EXTENDED = test_libbpf_open test_sock_addr
 
 include ../lib.mk
 
@@ -56,6 +57,7 @@ $(TEST_GEN_PROGS_EXTENDED): $(OUTPUT)/libbpf.a
 $(OUTPUT)/test_dev_cgroup: cgroup_helpers.c
 $(OUTPUT)/test_sock: cgroup_helpers.c
 $(OUTPUT)/test_sock_addr: cgroup_helpers.c
+$(OUTPUT)/test_sockmap: cgroup_helpers.c
 
 .PHONY: force
 
diff --git a/tools/testing/selftests/bpf/bpf_helpers.h b/tools/testing/selftests/bpf/bpf_helpers.h
index 9271576bdc8f..69d7b918e66a 100644
--- a/tools/testing/selftests/bpf/bpf_helpers.h
+++ b/tools/testing/selftests/bpf/bpf_helpers.h
@@ -98,7 +98,9 @@ static int (*bpf_bind)(void *ctx, void *addr, int addr_len) =
 	(void *) BPF_FUNC_bind;
 static int (*bpf_xdp_adjust_tail)(void *ctx, int offset) =
 	(void *) BPF_FUNC_xdp_adjust_tail;
-
+static int (*bpf_skb_get_xfrm_state)(void *ctx, int index, void *state,
+				     int size, int flags) =
+	(void *) BPF_FUNC_skb_get_xfrm_state;
 
 /* llvm builtin functions that eBPF C program may use to
  * emit BPF_LD_ABS and BPF_LD_IND instructions
diff --git a/samples/sockmap/sockmap_user.c b/tools/testing/selftests/bpf/test_sockmap.c
index 6f2334912283..29c022d23f4e 100644
--- a/samples/sockmap/sockmap_user.c
+++ b/tools/testing/selftests/bpf/test_sockmap.c
@@ -1,14 +1,5 @@
-/* Copyright (c) 2017 Covalent IO, Inc. http://covalent.io
- *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of version 2 of the GNU General Public
- * License as published by the Free Software Foundation.
- *
- * This program is distributed in the hope that it will be useful, but
- * WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
- * General Public License for more details.
- */
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (c) 2017-2018 Covalent IO, Inc. http://covalent.io
 #include <stdio.h>
 #include <stdlib.h>
 #include <sys/socket.h>
@@ -25,6 +16,7 @@
 #include <fcntl.h>
 #include <sys/wait.h>
 #include <time.h>
+#include <sched.h>
 
 #include <sys/time.h>
 #include <sys/resource.h>
@@ -41,19 +33,31 @@
 
 #include <getopt.h>
 
-#include "../bpf/bpf_load.h"
-#include "../bpf/bpf_util.h"
-#include "../bpf/libbpf.h"
+#include <bpf/bpf.h>
+#include <bpf/libbpf.h>
+
+#include "bpf_util.h"
+#include "bpf_rlimit.h"
+#include "cgroup_helpers.h"
 
 int running;
-void running_handler(int a);
+static void running_handler(int a);
 
 /* randomly selected ports for testing on lo */
 #define S1_PORT 10000
 #define S2_PORT 10001
 
+#define BPF_FILENAME "test_sockmap_kern.o"
+#define CG_PATH "/sockmap"
+
 /* global sockets */
 int s1, s2, c1, c2, p1, p2;
+int test_cnt;
+int passed;
+int failed;
+int map_fd[8];
+struct bpf_map *maps[8];
+int prog_fd[11];
 
 int txmsg_pass;
 int txmsg_noisy;
@@ -107,7 +111,7 @@ static void usage(char *argv[])
 	printf("\n");
 }
 
-static int sockmap_init_sockets(void)
+static int sockmap_init_sockets(int verbose)
 {
 	int i, err, one = 1;
 	struct sockaddr_in addr;
@@ -207,9 +211,11 @@ static int sockmap_init_sockets(void)
 		return errno;
 	}
 
-	printf("connected sockets: c1 <-> p1, c2 <-> p2\n");
-	printf("cgroups binding: c1(%i) <-> s1(%i) - - - c2(%i) <-> s2(%i)\n",
-		c1, s1, c2, s2);
+	if (verbose) {
+		printf("connected sockets: c1 <-> p1, c2 <-> p2\n");
+		printf("cgroups binding: c1(%i) <-> s1(%i) - - - c2(%i) <-> s2(%i)\n",
+			c1, s1, c2, s2);
+	}
 	return 0;
 }
 
@@ -226,6 +232,9 @@ struct sockmap_options {
 	bool sendpage;
 	bool data_test;
 	bool drop_expected;
+	int iov_count;
+	int iov_length;
+	int rate;
 };
 
 static int msg_loop_sendpage(int fd, int iov_length, int cnt,
@@ -324,17 +333,19 @@ static int msg_loop(int fd, int iov_count, int iov_length, int cnt,
 		clock_gettime(CLOCK_MONOTONIC, &s->end);
 	} else {
 		int slct, recv, max_fd = fd;
+		int fd_flags = O_NONBLOCK;
 		struct timeval timeout;
 		float total_bytes;
 		fd_set w;
 
+		fcntl(fd, fd_flags);
 		total_bytes = (float)iov_count * (float)iov_length * (float)cnt;
 		err = clock_gettime(CLOCK_MONOTONIC, &s->start);
 		if (err < 0)
 			perror("recv start time: ");
 		while (s->bytes_recvd < total_bytes) {
-			timeout.tv_sec = 1;
-			timeout.tv_usec = 0;
+			timeout.tv_sec = 0;
+			timeout.tv_usec = 10;
 
 			/* FD sets */
 			FD_ZERO(&w);
@@ -346,7 +357,8 @@ static int msg_loop(int fd, int iov_count, int iov_length, int cnt,
 				clock_gettime(CLOCK_MONOTONIC, &s->end);
 				goto out_errno;
 			} else if (!slct) {
-				fprintf(stderr, "unexpected timeout\n");
+				if (opt->verbose)
+					fprintf(stderr, "unexpected timeout\n");
 				errno = -EIO;
 				clock_gettime(CLOCK_MONOTONIC, &s->end);
 				goto out_errno;
@@ -409,12 +421,14 @@ static inline float recvdBps(struct msg_stats s)
 	return s.bytes_recvd / (s.end.tv_sec - s.start.tv_sec);
 }
 
-static int sendmsg_test(int iov_count, int iov_buf, int cnt,
-			struct sockmap_options *opt)
+static int sendmsg_test(struct sockmap_options *opt)
 {
 	float sent_Bps = 0, recvd_Bps = 0;
 	int rx_fd, txpid, rxpid, err = 0;
 	struct msg_stats s = {0};
+	int iov_count = opt->iov_count;
+	int iov_buf = opt->iov_length;
+	int cnt = opt->rate;
 	int status;
 
 	errno = 0;
@@ -433,7 +447,7 @@ static int sendmsg_test(int iov_count, int iov_buf, int cnt,
 			iov_count = 1;
 		err = msg_loop(rx_fd, iov_count, iov_buf,
 			       cnt, &s, false, opt);
-		if (err)
+		if (err && opt->verbose)
 			fprintf(stderr,
 				"msg_loop_rx: iov_count %i iov_buf %i cnt %i err %i\n",
 				iov_count, iov_buf, cnt, err);
@@ -443,10 +457,11 @@ static int sendmsg_test(int iov_count, int iov_buf, int cnt,
 			sent_Bps = sentBps(s);
 			recvd_Bps = recvdBps(s);
 		}
-		fprintf(stdout,
-			"rx_sendmsg: TX: %zuB %fB/s %fGB/s RX: %zuB %fB/s %fGB/s\n",
-			s.bytes_sent, sent_Bps, sent_Bps/giga,
-			s.bytes_recvd, recvd_Bps, recvd_Bps/giga);
+		if (opt->verbose)
+			fprintf(stdout,
+				"rx_sendmsg: TX: %zuB %fB/s %fGB/s RX: %zuB %fB/s %fGB/s\n",
+				s.bytes_sent, sent_Bps, sent_Bps/giga,
+				s.bytes_recvd, recvd_Bps, recvd_Bps/giga);
 		exit(1);
 	} else if (rxpid == -1) {
 		perror("msg_loop_rx: ");
@@ -470,10 +485,11 @@ static int sendmsg_test(int iov_count, int iov_buf, int cnt,
 			sent_Bps = sentBps(s);
 			recvd_Bps = recvdBps(s);
 		}
-		fprintf(stdout,
-			"tx_sendmsg: TX: %zuB %fB/s %f GB/s RX: %zuB %fB/s %fGB/s\n",
-			s.bytes_sent, sent_Bps, sent_Bps/giga,
-			s.bytes_recvd, recvd_Bps, recvd_Bps/giga);
+		if (opt->verbose)
+			fprintf(stdout,
+				"tx_sendmsg: TX: %zuB %fB/s %f GB/s RX: %zuB %fB/s %fGB/s\n",
+				s.bytes_sent, sent_Bps, sent_Bps/giga,
+				s.bytes_recvd, recvd_Bps, recvd_Bps/giga);
 		exit(1);
 	} else if (txpid == -1) {
 		perror("msg_loop_tx: ");
@@ -568,102 +584,9 @@ enum {
 	SENDPAGE,
 };
 
-int main(int argc, char **argv)
+static int run_options(struct sockmap_options *options, int cg_fd,  int test)
 {
-	int iov_count = 1, length = 1024, rate = 1, tx_prog_fd;
-	struct rlimit r = {10 * 1024 * 1024, RLIM_INFINITY};
-	int opt, longindex, err, cg_fd = 0;
-	struct sockmap_options options = {0};
-	int test = PING_PONG;
-	char filename[256];
-
-	while ((opt = getopt_long(argc, argv, ":dhvc:r:i:l:t:",
-				  long_options, &longindex)) != -1) {
-		switch (opt) {
-		case 's':
-			txmsg_start = atoi(optarg);
-			break;
-		case 'e':
-			txmsg_end = atoi(optarg);
-			break;
-		case 'a':
-			txmsg_apply = atoi(optarg);
-			break;
-		case 'k':
-			txmsg_cork = atoi(optarg);
-			break;
-		case 'c':
-			cg_fd = open(optarg, O_DIRECTORY, O_RDONLY);
-			if (cg_fd < 0) {
-				fprintf(stderr,
-					"ERROR: (%i) open cg path failed: %s\n",
-					cg_fd, optarg);
-				return cg_fd;
-			}
-			break;
-		case 'r':
-			rate = atoi(optarg);
-			break;
-		case 'v':
-			options.verbose = 1;
-			break;
-		case 'i':
-			iov_count = atoi(optarg);
-			break;
-		case 'l':
-			length = atoi(optarg);
-			break;
-		case 'd':
-			options.data_test = true;
-			break;
-		case 't':
-			if (strcmp(optarg, "ping") == 0) {
-				test = PING_PONG;
-			} else if (strcmp(optarg, "sendmsg") == 0) {
-				test = SENDMSG;
-			} else if (strcmp(optarg, "base") == 0) {
-				test = BASE;
-			} else if (strcmp(optarg, "base_sendpage") == 0) {
-				test = BASE_SENDPAGE;
-			} else if (strcmp(optarg, "sendpage") == 0) {
-				test = SENDPAGE;
-			} else {
-				usage(argv);
-				return -1;
-			}
-			break;
-		case 0:
-			break;
-		case 'h':
-		default:
-			usage(argv);
-			return -1;
-		}
-	}
-
-	if (!cg_fd) {
-		fprintf(stderr, "%s requires cgroup option: --cgroup <path>\n",
-			argv[0]);
-		return -1;
-	}
-
-	if (setrlimit(RLIMIT_MEMLOCK, &r)) {
-		perror("setrlimit(RLIMIT_MEMLOCK)");
-		return 1;
-	}
-
-	snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]);
-
-	running = 1;
-
-	/* catch SIGINT */
-	signal(SIGINT, running_handler);
-
-	if (load_bpf_file(filename)) {
-		fprintf(stderr, "load_bpf_file: (%s) %s\n",
-			filename, strerror(errno));
-		return 1;
-	}
+	int i, key, next_key, err, tx_prog_fd = -1, zero = 0;
 
 	/* If base test skip BPF setup */
 	if (test == BASE || test == BASE_SENDPAGE)
@@ -673,8 +596,9 @@ int main(int argc, char **argv)
 	err = bpf_prog_attach(prog_fd[0], map_fd[0],
 				BPF_SK_SKB_STREAM_PARSER, 0);
 	if (err) {
-		fprintf(stderr, "ERROR: bpf_prog_attach (sockmap): %d (%s)\n",
-			err, strerror(errno));
+		fprintf(stderr,
+			"ERROR: bpf_prog_attach (sockmap %i->%i): %d (%s)\n",
+			prog_fd[0], map_fd[0], err, strerror(errno));
 		return err;
 	}
 
@@ -695,7 +619,7 @@ int main(int argc, char **argv)
 	}
 
 run:
-	err = sockmap_init_sockets();
+	err = sockmap_init_sockets(options->verbose);
 	if (err) {
 		fprintf(stderr, "ERROR: test socket failed: %d\n", err);
 		goto out;
@@ -729,7 +653,7 @@ run:
 			fprintf(stderr,
 				"ERROR: bpf_prog_attach (txmsg): %d (%s)\n",
 				err, strerror(errno));
-			return err;
+			goto out;
 		}
 
 		err = bpf_map_update_elem(map_fd[1], &i, &c1, BPF_ANY);
@@ -737,7 +661,7 @@ run:
 			fprintf(stderr,
 				"ERROR: bpf_map_update_elem (txmsg):  %d (%s\n",
 				err, strerror(errno));
-			return err;
+			goto out;
 		}
 
 		if (txmsg_redir || txmsg_redir_noisy)
@@ -750,7 +674,7 @@ run:
 			fprintf(stderr,
 				"ERROR: bpf_map_update_elem (txmsg):  %d (%s\n",
 				err, strerror(errno));
-			return err;
+			goto out;
 		}
 
 		if (txmsg_apply) {
@@ -760,7 +684,7 @@ run:
 				fprintf(stderr,
 					"ERROR: bpf_map_update_elem (apply_bytes):  %d (%s\n",
 					err, strerror(errno));
-				return err;
+				goto out;
 			}
 		}
 
@@ -771,7 +695,7 @@ run:
 				fprintf(stderr,
 					"ERROR: bpf_map_update_elem (cork_bytes):  %d (%s\n",
 					err, strerror(errno));
-				return err;
+				goto out;
 			}
 		}
 
@@ -782,7 +706,7 @@ run:
 				fprintf(stderr,
 					"ERROR: bpf_map_update_elem (txmsg_start):  %d (%s)\n",
 					err, strerror(errno));
-				return err;
+				goto out;
 			}
 		}
 
@@ -794,7 +718,7 @@ run:
 				fprintf(stderr,
 					"ERROR: bpf_map_update_elem (txmsg_end):  %d (%s)\n",
 					err, strerror(errno));
-				return err;
+				goto out;
 			}
 		}
 
@@ -832,11 +756,13 @@ run:
 		}
 
 		if (txmsg_skb) {
-			int skb_fd = (test == SENDMSG || test == SENDPAGE) ? p2 : p1;
+			int skb_fd = (test == SENDMSG || test == SENDPAGE) ?
+					p2 : p1;
 			int ingress = BPF_F_INGRESS;
 
 			i = 0;
-			err = bpf_map_update_elem(map_fd[7], &i, &ingress, BPF_ANY);
+			err = bpf_map_update_elem(map_fd[7],
+						  &i, &ingress, BPF_ANY);
 			if (err) {
 				fprintf(stderr,
 					"ERROR: bpf_map_update_elem (txmsg_ingress): %d (%s)\n",
@@ -844,7 +770,8 @@ run:
 			}
 
 			i = 3;
-			err = bpf_map_update_elem(map_fd[0], &i, &skb_fd, BPF_ANY);
+			err = bpf_map_update_elem(map_fd[0],
+						  &i, &skb_fd, BPF_ANY);
 			if (err) {
 				fprintf(stderr,
 					"ERROR: bpf_map_update_elem (c1 sockmap): %d (%s)\n",
@@ -854,36 +781,679 @@ run:
 	}
 
 	if (txmsg_drop)
-		options.drop_expected = true;
+		options->drop_expected = true;
 
 	if (test == PING_PONG)
-		err = forever_ping_pong(rate, &options);
+		err = forever_ping_pong(options->rate, options);
 	else if (test == SENDMSG) {
-		options.base = false;
-		options.sendpage = false;
-		err = sendmsg_test(iov_count, length, rate, &options);
+		options->base = false;
+		options->sendpage = false;
+		err = sendmsg_test(options);
 	} else if (test == SENDPAGE) {
-		options.base = false;
-		options.sendpage = true;
-		err = sendmsg_test(iov_count, length, rate, &options);
+		options->base = false;
+		options->sendpage = true;
+		err = sendmsg_test(options);
 	} else if (test == BASE) {
-		options.base = true;
-		options.sendpage = false;
-		err = sendmsg_test(iov_count, length, rate, &options);
+		options->base = true;
+		options->sendpage = false;
+		err = sendmsg_test(options);
 	} else if (test == BASE_SENDPAGE) {
-		options.base = true;
-		options.sendpage = true;
-		err = sendmsg_test(iov_count, length, rate, &options);
+		options->base = true;
+		options->sendpage = true;
+		err = sendmsg_test(options);
 	} else
 		fprintf(stderr, "unknown test\n");
 out:
+	/* Detatch and zero all the maps */
 	bpf_prog_detach2(prog_fd[2], cg_fd, BPF_CGROUP_SOCK_OPS);
+	bpf_prog_detach2(prog_fd[0], map_fd[0], BPF_SK_SKB_STREAM_PARSER);
+	bpf_prog_detach2(prog_fd[1], map_fd[0], BPF_SK_SKB_STREAM_VERDICT);
+	if (tx_prog_fd >= 0)
+		bpf_prog_detach2(tx_prog_fd, map_fd[1], BPF_SK_MSG_VERDICT);
+
+	for (i = 0; i < 8; i++) {
+		key = next_key = 0;
+		bpf_map_update_elem(map_fd[i], &key, &zero, BPF_ANY);
+		while (bpf_map_get_next_key(map_fd[i], &key, &next_key) == 0) {
+			bpf_map_update_elem(map_fd[i], &key, &zero, BPF_ANY);
+			key = next_key;
+		}
+	}
+
 	close(s1);
 	close(s2);
 	close(p1);
 	close(p2);
 	close(c1);
 	close(c2);
+	return err;
+}
+
+static char *test_to_str(int test)
+{
+	switch (test) {
+	case SENDMSG:
+		return "sendmsg";
+	case SENDPAGE:
+		return "sendpage";
+	}
+	return "unknown";
+}
+
+#define OPTSTRING 60
+static void test_options(char *options)
+{
+	memset(options, 0, OPTSTRING);
+
+	if (txmsg_pass)
+		strncat(options, "pass,", OPTSTRING);
+	if (txmsg_noisy)
+		strncat(options, "pass_noisy,", OPTSTRING);
+	if (txmsg_redir)
+		strncat(options, "redir,", OPTSTRING);
+	if (txmsg_redir_noisy)
+		strncat(options, "redir_noisy,", OPTSTRING);
+	if (txmsg_drop)
+		strncat(options, "drop,", OPTSTRING);
+	if (txmsg_apply)
+		strncat(options, "apply,", OPTSTRING);
+	if (txmsg_cork)
+		strncat(options, "cork,", OPTSTRING);
+	if (txmsg_start)
+		strncat(options, "start,", OPTSTRING);
+	if (txmsg_end)
+		strncat(options, "end,", OPTSTRING);
+	if (txmsg_ingress)
+		strncat(options, "ingress,", OPTSTRING);
+	if (txmsg_skb)
+		strncat(options, "skb,", OPTSTRING);
+}
+
+static int __test_exec(int cgrp, int test, struct sockmap_options *opt)
+{
+	char *options = calloc(60, sizeof(char));
+	int err;
+
+	if (test == SENDPAGE)
+		opt->sendpage = true;
+	else
+		opt->sendpage = false;
+
+	if (txmsg_drop)
+		opt->drop_expected = true;
+	else
+		opt->drop_expected = false;
+
+	test_options(options);
+
+	fprintf(stdout,
+		"[TEST %i]: (%i, %i, %i, %s, %s): ",
+		test_cnt, opt->rate, opt->iov_count, opt->iov_length,
+		test_to_str(test), options);
+	fflush(stdout);
+	err = run_options(opt, cgrp, test);
+	fprintf(stdout, "%s\n", !err ? "PASS" : "FAILED");
+	test_cnt++;
+	!err ? passed++ : failed++;
+	free(options);
+	return err;
+}
+
+static int test_exec(int cgrp, struct sockmap_options *opt)
+{
+	int err = __test_exec(cgrp, SENDMSG, opt);
+
+	if (err)
+		goto out;
+
+	err = __test_exec(cgrp, SENDPAGE, opt);
+out:
+	return err;
+}
+
+static int test_loop(int cgrp)
+{
+	struct sockmap_options opt;
+
+	int err, i, l, r;
+
+	opt.verbose = 0;
+	opt.base = false;
+	opt.sendpage = false;
+	opt.data_test = false;
+	opt.drop_expected = false;
+	opt.iov_count = 0;
+	opt.iov_length = 0;
+	opt.rate = 0;
+
+	r = 1;
+	for (i = 1; i < 100; i += 33) {
+		for (l = 1; l < 100; l += 33) {
+			opt.rate = r;
+			opt.iov_count = i;
+			opt.iov_length = l;
+			err = test_exec(cgrp, &opt);
+			if (err)
+				goto out;
+		}
+	}
+	sched_yield();
+out:
+	return err;
+}
+
+static int test_txmsg(int cgrp)
+{
+	int err;
+
+	txmsg_pass = txmsg_noisy = txmsg_redir_noisy = txmsg_drop = 0;
+	txmsg_apply = txmsg_cork = 0;
+	txmsg_ingress = txmsg_skb = 0;
+
+	txmsg_pass = 1;
+	err = test_loop(cgrp);
+	txmsg_pass = 0;
+	if (err)
+		goto out;
+
+	txmsg_redir = 1;
+	err = test_loop(cgrp);
+	txmsg_redir = 0;
+	if (err)
+		goto out;
+
+	txmsg_drop = 1;
+	err = test_loop(cgrp);
+	txmsg_drop = 0;
+	if (err)
+		goto out;
+
+	txmsg_redir = 1;
+	txmsg_ingress = 1;
+	err = test_loop(cgrp);
+	txmsg_redir = 0;
+	txmsg_ingress = 0;
+	if (err)
+		goto out;
+out:
+	txmsg_pass = 0;
+	txmsg_redir = 0;
+	txmsg_drop = 0;
+	return err;
+}
+
+static int test_send(struct sockmap_options *opt, int cgrp)
+{
+	int err;
+
+	opt->iov_length = 1;
+	opt->iov_count = 1;
+	opt->rate = 1;
+	err = test_exec(cgrp, opt);
+	if (err)
+		goto out;
+
+	opt->iov_length = 1;
+	opt->iov_count = 1024;
+	opt->rate = 1;
+	err = test_exec(cgrp, opt);
+	if (err)
+		goto out;
+
+	opt->iov_length = 1024;
+	opt->iov_count = 1;
+	opt->rate = 1;
+	err = test_exec(cgrp, opt);
+	if (err)
+		goto out;
+
+	opt->iov_length = 1;
+	opt->iov_count = 1;
+	opt->rate = 1024;
+	err = test_exec(cgrp, opt);
+	if (err)
+		goto out;
+
+	opt->iov_length = 256;
+	opt->iov_count = 1024;
+	opt->rate = 10;
+	err = test_exec(cgrp, opt);
+	if (err)
+		goto out;
+
+	opt->rate = 100;
+	opt->iov_count = 1;
+	opt->iov_length = 5;
+	err = test_exec(cgrp, opt);
+	if (err)
+		goto out;
+out:
+	sched_yield();
+	return err;
+}
+
+static int test_mixed(int cgrp)
+{
+	struct sockmap_options opt = {0};
+	int err;
+
+	txmsg_pass = txmsg_noisy = txmsg_redir_noisy = txmsg_drop = 0;
+	txmsg_apply = txmsg_cork = 0;
+	txmsg_start = txmsg_end = 0;
+	/* Test small and large iov_count values with pass/redir/apply/cork */
+	txmsg_pass = 1;
+	txmsg_redir = 0;
+	txmsg_apply = 1;
+	txmsg_cork = 0;
+	err = test_send(&opt, cgrp);
+	if (err)
+		goto out;
+
+	txmsg_pass = 1;
+	txmsg_redir = 0;
+	txmsg_apply = 0;
+	txmsg_cork = 1;
+	err = test_send(&opt, cgrp);
+	if (err)
+		goto out;
+
+	txmsg_pass = 1;
+	txmsg_redir = 0;
+	txmsg_apply = 1;
+	txmsg_cork = 1;
+	err = test_send(&opt, cgrp);
+	if (err)
+		goto out;
+
+	txmsg_pass = 1;
+	txmsg_redir = 0;
+	txmsg_apply = 1024;
+	txmsg_cork = 0;
+	err = test_send(&opt, cgrp);
+	if (err)
+		goto out;
+
+	txmsg_pass = 1;
+	txmsg_redir = 0;
+	txmsg_apply = 0;
+	txmsg_cork = 1024;
+	err = test_send(&opt, cgrp);
+	if (err)
+		goto out;
+
+	txmsg_pass = 1;
+	txmsg_redir = 0;
+	txmsg_apply = 1024;
+	txmsg_cork = 1024;
+	err = test_send(&opt, cgrp);
+	if (err)
+		goto out;
+
+	txmsg_pass = 1;
+	txmsg_redir = 0;
+	txmsg_cork = 4096;
+	txmsg_apply = 4096;
+	err = test_send(&opt, cgrp);
+	if (err)
+		goto out;
+
+	txmsg_pass = 0;
+	txmsg_redir = 1;
+	txmsg_apply = 1;
+	txmsg_cork = 0;
+	err = test_send(&opt, cgrp);
+	if (err)
+		goto out;
+
+	txmsg_pass = 0;
+	txmsg_redir = 1;
+	txmsg_apply = 0;
+	txmsg_cork = 1;
+	err = test_send(&opt, cgrp);
+	if (err)
+		goto out;
+
+	txmsg_pass = 0;
+	txmsg_redir = 1;
+	txmsg_apply = 1024;
+	txmsg_cork = 0;
+	err = test_send(&opt, cgrp);
+	if (err)
+		goto out;
+
+	txmsg_pass = 0;
+	txmsg_redir = 1;
+	txmsg_apply = 0;
+	txmsg_cork = 1024;
+	err = test_send(&opt, cgrp);
+	if (err)
+		goto out;
+
+	txmsg_pass = 0;
+	txmsg_redir = 1;
+	txmsg_apply = 1024;
+	txmsg_cork = 1024;
+	err = test_send(&opt, cgrp);
+	if (err)
+		goto out;
+
+	txmsg_pass = 0;
+	txmsg_redir = 1;
+	txmsg_cork = 4096;
+	txmsg_apply = 4096;
+	err = test_send(&opt, cgrp);
+	if (err)
+		goto out;
+out:
+	return err;
+}
+
+static int test_start_end(int cgrp)
+{
+	struct sockmap_options opt = {0};
+	int err, i;
+
+	/* Test basic start/end with lots of iov_count and iov_lengths */
+	txmsg_start = 1;
+	txmsg_end = 2;
+	err = test_txmsg(cgrp);
+	if (err)
+		goto out;
+
+	/* Test start/end with cork */
+	opt.rate = 16;
+	opt.iov_count = 1;
+	opt.iov_length = 100;
+	txmsg_cork = 1600;
+
+	for (i = 99; i <= 1600; i += 500) {
+		txmsg_start = 0;
+		txmsg_end = i;
+		err = test_exec(cgrp, &opt);
+		if (err)
+			goto out;
+	}
+
+	/* Test start/end with cork but pull data in middle */
+	for (i = 199; i <= 1600; i += 500) {
+		txmsg_start = 100;
+		txmsg_end = i;
+		err = test_exec(cgrp, &opt);
+		if (err)
+			goto out;
+	}
+
+	/* Test start/end with cork pulling last sg entry */
+	txmsg_start = 1500;
+	txmsg_end = 1600;
+	err = test_exec(cgrp, &opt);
+	if (err)
+		goto out;
+
+	/* Test start/end pull of single byte in last page */
+	txmsg_start = 1111;
+	txmsg_end = 1112;
+	err = test_exec(cgrp, &opt);
+	if (err)
+		goto out;
+
+	/* Test start/end with end < start */
+	txmsg_start = 1111;
+	txmsg_end = 0;
+	err = test_exec(cgrp, &opt);
+	if (err)
+		goto out;
+
+	/* Test start/end with end > data */
+	txmsg_start = 0;
+	txmsg_end = 1601;
+	err = test_exec(cgrp, &opt);
+	if (err)
+		goto out;
+
+	/* Test start/end with start > data */
+	txmsg_start = 1601;
+	txmsg_end = 1600;
+	err = test_exec(cgrp, &opt);
+
+out:
+	txmsg_start = 0;
+	txmsg_end = 0;
+	sched_yield();
+	return err;
+}
+
+char *map_names[] = {
+	"sock_map",
+	"sock_map_txmsg",
+	"sock_map_redir",
+	"sock_apply_bytes",
+	"sock_cork_bytes",
+	"sock_pull_bytes",
+	"sock_redir_flags",
+	"sock_skb_opts",
+};
+
+int prog_attach_type[] = {
+	BPF_SK_SKB_STREAM_PARSER,
+	BPF_SK_SKB_STREAM_VERDICT,
+	BPF_CGROUP_SOCK_OPS,
+	BPF_SK_MSG_VERDICT,
+	BPF_SK_MSG_VERDICT,
+	BPF_SK_MSG_VERDICT,
+	BPF_SK_MSG_VERDICT,
+	BPF_SK_MSG_VERDICT,
+	BPF_SK_MSG_VERDICT,
+	BPF_SK_MSG_VERDICT,
+};
+
+int prog_type[] = {
+	BPF_PROG_TYPE_SK_SKB,
+	BPF_PROG_TYPE_SK_SKB,
+	BPF_PROG_TYPE_SOCK_OPS,
+	BPF_PROG_TYPE_SK_MSG,
+	BPF_PROG_TYPE_SK_MSG,
+	BPF_PROG_TYPE_SK_MSG,
+	BPF_PROG_TYPE_SK_MSG,
+	BPF_PROG_TYPE_SK_MSG,
+	BPF_PROG_TYPE_SK_MSG,
+	BPF_PROG_TYPE_SK_MSG,
+};
+
+static int populate_progs(void)
+{
+	char *bpf_file = BPF_FILENAME;
+	struct bpf_program *prog;
+	struct bpf_object *obj;
+	int i = 0;
+	long err;
+
+	obj = bpf_object__open(bpf_file);
+	err = libbpf_get_error(obj);
+	if (err) {
+		char err_buf[256];
+
+		libbpf_strerror(err, err_buf, sizeof(err_buf));
+		printf("Unable to load eBPF objects in file '%s' : %s\n",
+		       bpf_file, err_buf);
+		return -1;
+	}
+
+	bpf_object__for_each_program(prog, obj) {
+		bpf_program__set_type(prog, prog_type[i]);
+		bpf_program__set_expected_attach_type(prog,
+						      prog_attach_type[i]);
+		i++;
+	}
+
+	i = bpf_object__load(obj);
+	i = 0;
+	bpf_object__for_each_program(prog, obj) {
+		prog_fd[i] = bpf_program__fd(prog);
+		i++;
+	}
+
+	for (i = 0; i < sizeof(map_fd)/sizeof(int); i++) {
+		maps[i] = bpf_object__find_map_by_name(obj, map_names[i]);
+		map_fd[i] = bpf_map__fd(maps[i]);
+		if (map_fd[i] < 0) {
+			fprintf(stderr, "load_bpf_file: (%i) %s\n",
+				map_fd[i], strerror(errno));
+			return -1;
+		}
+	}
+
+	return 0;
+}
+
+static int test_suite(void)
+{
+	int cg_fd, err;
+
+	err = populate_progs();
+	if (err < 0) {
+		fprintf(stderr, "ERROR: (%i) load bpf failed\n", err);
+		return err;
+	}
+
+	if (setup_cgroup_environment()) {
+		fprintf(stderr, "ERROR: cgroup env failed\n");
+		return -EINVAL;
+	}
+
+	cg_fd = create_and_get_cgroup(CG_PATH);
+	if (cg_fd < 0) {
+		fprintf(stderr,
+			"ERROR: (%i) open cg path failed: %s\n",
+			cg_fd, optarg);
+		return cg_fd;
+	}
+
+	/* Tests basic commands and APIs with range of iov values */
+	txmsg_start = txmsg_end = 0;
+	err = test_txmsg(cg_fd);
+	if (err)
+		goto out;
+
+	/* Tests interesting combinations of APIs used together */
+	err = test_mixed(cg_fd);
+	if (err)
+		goto out;
+
+	/* Tests pull_data API using start/end API */
+	err = test_start_end(cg_fd);
+	if (err)
+		goto out;
+
+out:
+	printf("Summary: %i PASSED %i FAILED\n", passed, failed);
+	close(cg_fd);
+	return err;
+}
+
+int main(int argc, char **argv)
+{
+	struct rlimit r = {10 * 1024 * 1024, RLIM_INFINITY};
+	int iov_count = 1, length = 1024, rate = 1;
+	struct sockmap_options options = {0};
+	int opt, longindex, err, cg_fd = 0;
+	char *bpf_file = BPF_FILENAME;
+	int test = PING_PONG;
+
+	if (setrlimit(RLIMIT_MEMLOCK, &r)) {
+		perror("setrlimit(RLIMIT_MEMLOCK)");
+		return 1;
+	}
+
+	if (argc < 2)
+		return test_suite();
+
+	while ((opt = getopt_long(argc, argv, ":dhvc:r:i:l:t:",
+				  long_options, &longindex)) != -1) {
+		switch (opt) {
+		case 's':
+			txmsg_start = atoi(optarg);
+			break;
+		case 'e':
+			txmsg_end = atoi(optarg);
+			break;
+		case 'a':
+			txmsg_apply = atoi(optarg);
+			break;
+		case 'k':
+			txmsg_cork = atoi(optarg);
+			break;
+		case 'c':
+			cg_fd = open(optarg, O_DIRECTORY, O_RDONLY);
+			if (cg_fd < 0) {
+				fprintf(stderr,
+					"ERROR: (%i) open cg path failed: %s\n",
+					cg_fd, optarg);
+				return cg_fd;
+			}
+			break;
+		case 'r':
+			rate = atoi(optarg);
+			break;
+		case 'v':
+			options.verbose = 1;
+			break;
+		case 'i':
+			iov_count = atoi(optarg);
+			break;
+		case 'l':
+			length = atoi(optarg);
+			break;
+		case 'd':
+			options.data_test = true;
+			break;
+		case 't':
+			if (strcmp(optarg, "ping") == 0) {
+				test = PING_PONG;
+			} else if (strcmp(optarg, "sendmsg") == 0) {
+				test = SENDMSG;
+			} else if (strcmp(optarg, "base") == 0) {
+				test = BASE;
+			} else if (strcmp(optarg, "base_sendpage") == 0) {
+				test = BASE_SENDPAGE;
+			} else if (strcmp(optarg, "sendpage") == 0) {
+				test = SENDPAGE;
+			} else {
+				usage(argv);
+				return -1;
+			}
+			break;
+		case 0:
+			break;
+		case 'h':
+		default:
+			usage(argv);
+			return -1;
+		}
+	}
+
+	if (!cg_fd) {
+		fprintf(stderr, "%s requires cgroup option: --cgroup <path>\n",
+			argv[0]);
+		return -1;
+	}
+
+	err = populate_progs();
+	if (err) {
+		fprintf(stderr, "populate program: (%s) %s\n",
+			bpf_file, strerror(errno));
+		return 1;
+	}
+	running = 1;
+
+	/* catch SIGINT */
+	signal(SIGINT, running_handler);
+
+	options.iov_count = iov_count;
+	options.iov_length = length;
+	options.rate = rate;
+
+	err = run_options(&options, cg_fd, test);
 	close(cg_fd);
 	return err;
 }
diff --git a/samples/sockmap/sockmap_kern.c b/tools/testing/selftests/bpf/test_sockmap_kern.c
index 9ff8bc5dc206..33de97e2b6b6 100644
--- a/samples/sockmap/sockmap_kern.c
+++ b/tools/testing/selftests/bpf/test_sockmap_kern.c
@@ -1,20 +1,19 @@
-/* Copyright (c) 2017 Covalent IO, Inc. http://covalent.io
- *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of version 2 of the GNU General Public
- * License as published by the Free Software Foundation.
- *
- * This program is distributed in the hope that it will be useful, but
- * WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
- * General Public License for more details.
- */
-#include <uapi/linux/bpf.h>
-#include <uapi/linux/if_ether.h>
-#include <uapi/linux/if_packet.h>
-#include <uapi/linux/ip.h>
-#include "../../tools/testing/selftests/bpf/bpf_helpers.h"
-#include "../../tools/testing/selftests/bpf/bpf_endian.h"
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (c) 2017-2018 Covalent IO, Inc. http://covalent.io
+#include <stddef.h>
+#include <string.h>
+#include <linux/bpf.h>
+#include <linux/if_ether.h>
+#include <linux/if_packet.h>
+#include <linux/ip.h>
+#include <linux/ipv6.h>
+#include <linux/in.h>
+#include <linux/udp.h>
+#include <linux/tcp.h>
+#include <linux/pkt_cls.h>
+#include <sys/socket.h>
+#include "bpf_helpers.h"
+#include "bpf_endian.h"
 
 /* Sockmap sample program connects a client and a backend together
  * using cgroups.
@@ -337,5 +336,5 @@ int bpf_prog10(struct sk_msg_md *msg)
 	return SK_DROP;
 }
 
-
+int _version SEC("version") = 1;
 char _license[] SEC("license") = "GPL";
diff --git a/tools/testing/selftests/bpf/test_tunnel.sh b/tools/testing/selftests/bpf/test_tunnel.sh
new file mode 100755
index 000000000000..aeb2901f21f4
--- /dev/null
+++ b/tools/testing/selftests/bpf/test_tunnel.sh
@@ -0,0 +1,729 @@
+#!/bin/bash
+# SPDX-License-Identifier: GPL-2.0
+
+# End-to-end eBPF tunnel test suite
+#   The script tests BPF network tunnel implementation.
+#
+# Topology:
+# ---------
+#     root namespace   |     at_ns0 namespace
+#                      |
+#      -----------     |     -----------
+#      | tnl dev |     |     | tnl dev |  (overlay network)
+#      -----------     |     -----------
+#      metadata-mode   |     native-mode
+#       with bpf       |
+#                      |
+#      ----------      |     ----------
+#      |  veth1  | --------- |  veth0  |  (underlay network)
+#      ----------    peer    ----------
+#
+#
+# Device Configuration
+# --------------------
+# Root namespace with metadata-mode tunnel + BPF
+# Device names and addresses:
+# 	veth1 IP: 172.16.1.200, IPv6: 00::22 (underlay)
+# 	tunnel dev <type>11, ex: gre11, IPv4: 10.1.1.200 (overlay)
+#
+# Namespace at_ns0 with native tunnel
+# Device names and addresses:
+# 	veth0 IPv4: 172.16.1.100, IPv6: 00::11 (underlay)
+# 	tunnel dev <type>00, ex: gre00, IPv4: 10.1.1.100 (overlay)
+#
+#
+# End-to-end ping packet flow
+# ---------------------------
+# Most of the tests start by namespace creation, device configuration,
+# then ping the underlay and overlay network.  When doing 'ping 10.1.1.100'
+# from root namespace, the following operations happen:
+# 1) Route lookup shows 10.1.1.100/24 belongs to tnl dev, fwd to tnl dev.
+# 2) Tnl device's egress BPF program is triggered and set the tunnel metadata,
+#    with remote_ip=172.16.1.200 and others.
+# 3) Outer tunnel header is prepended and route the packet to veth1's egress
+# 4) veth0's ingress queue receive the tunneled packet at namespace at_ns0
+# 5) Tunnel protocol handler, ex: vxlan_rcv, decap the packet
+# 6) Forward the packet to the overlay tnl dev
+
+PING_ARG="-c 3 -w 10 -q"
+ret=0
+GREEN='\033[0;92m'
+RED='\033[0;31m'
+NC='\033[0m' # No Color
+
+config_device()
+{
+	ip netns add at_ns0
+	ip link add veth0 type veth peer name veth1
+	ip link set veth0 netns at_ns0
+	ip netns exec at_ns0 ip addr add 172.16.1.100/24 dev veth0
+	ip netns exec at_ns0 ip link set dev veth0 up
+	ip link set dev veth1 up mtu 1500
+	ip addr add dev veth1 172.16.1.200/24
+}
+
+add_gre_tunnel()
+{
+	# at_ns0 namespace
+	ip netns exec at_ns0 \
+        ip link add dev $DEV_NS type $TYPE seq key 2 \
+		local 172.16.1.100 remote 172.16.1.200
+	ip netns exec at_ns0 ip link set dev $DEV_NS up
+	ip netns exec at_ns0 ip addr add dev $DEV_NS 10.1.1.100/24
+
+	# root namespace
+	ip link add dev $DEV type $TYPE key 2 external
+	ip link set dev $DEV up
+	ip addr add dev $DEV 10.1.1.200/24
+}
+
+add_ip6gretap_tunnel()
+{
+
+	# assign ipv6 address
+	ip netns exec at_ns0 ip addr add ::11/96 dev veth0
+	ip netns exec at_ns0 ip link set dev veth0 up
+	ip addr add dev veth1 ::22/96
+	ip link set dev veth1 up
+
+	# at_ns0 namespace
+	ip netns exec at_ns0 \
+		ip link add dev $DEV_NS type $TYPE seq flowlabel 0xbcdef key 2 \
+		local ::11 remote ::22
+
+	ip netns exec at_ns0 ip addr add dev $DEV_NS 10.1.1.100/24
+	ip netns exec at_ns0 ip addr add dev $DEV_NS fc80::100/96
+	ip netns exec at_ns0 ip link set dev $DEV_NS up
+
+	# root namespace
+	ip link add dev $DEV type $TYPE external
+	ip addr add dev $DEV 10.1.1.200/24
+	ip addr add dev $DEV fc80::200/24
+	ip link set dev $DEV up
+}
+
+add_erspan_tunnel()
+{
+	# at_ns0 namespace
+	if [ "$1" == "v1" ]; then
+		ip netns exec at_ns0 \
+		ip link add dev $DEV_NS type $TYPE seq key 2 \
+		local 172.16.1.100 remote 172.16.1.200 \
+		erspan_ver 1 erspan 123
+	else
+		ip netns exec at_ns0 \
+		ip link add dev $DEV_NS type $TYPE seq key 2 \
+		local 172.16.1.100 remote 172.16.1.200 \
+		erspan_ver 2 erspan_dir egress erspan_hwid 3
+	fi
+	ip netns exec at_ns0 ip link set dev $DEV_NS up
+	ip netns exec at_ns0 ip addr add dev $DEV_NS 10.1.1.100/24
+
+	# root namespace
+	ip link add dev $DEV type $TYPE external
+	ip link set dev $DEV up
+	ip addr add dev $DEV 10.1.1.200/24
+}
+
+add_ip6erspan_tunnel()
+{
+
+	# assign ipv6 address
+	ip netns exec at_ns0 ip addr add ::11/96 dev veth0
+	ip netns exec at_ns0 ip link set dev veth0 up
+	ip addr add dev veth1 ::22/96
+	ip link set dev veth1 up
+
+	# at_ns0 namespace
+	if [ "$1" == "v1" ]; then
+		ip netns exec at_ns0 \
+		ip link add dev $DEV_NS type $TYPE seq key 2 \
+		local ::11 remote ::22 \
+		erspan_ver 1 erspan 123
+	else
+		ip netns exec at_ns0 \
+		ip link add dev $DEV_NS type $TYPE seq key 2 \
+		local ::11 remote ::22 \
+		erspan_ver 2 erspan_dir egress erspan_hwid 7
+	fi
+	ip netns exec at_ns0 ip addr add dev $DEV_NS 10.1.1.100/24
+	ip netns exec at_ns0 ip link set dev $DEV_NS up
+
+	# root namespace
+	ip link add dev $DEV type $TYPE external
+	ip addr add dev $DEV 10.1.1.200/24
+	ip link set dev $DEV up
+}
+
+add_vxlan_tunnel()
+{
+	# Set static ARP entry here because iptables set-mark works
+	# on L3 packet, as a result not applying to ARP packets,
+	# causing errors at get_tunnel_{key/opt}.
+
+	# at_ns0 namespace
+	ip netns exec at_ns0 \
+		ip link add dev $DEV_NS type $TYPE \
+		id 2 dstport 4789 gbp remote 172.16.1.200
+	ip netns exec at_ns0 \
+		ip link set dev $DEV_NS address 52:54:00:d9:01:00 up
+	ip netns exec at_ns0 ip addr add dev $DEV_NS 10.1.1.100/24
+	ip netns exec at_ns0 arp -s 10.1.1.200 52:54:00:d9:02:00
+	ip netns exec at_ns0 iptables -A OUTPUT -j MARK --set-mark 0x800FF
+
+	# root namespace
+	ip link add dev $DEV type $TYPE external gbp dstport 4789
+	ip link set dev $DEV address 52:54:00:d9:02:00 up
+	ip addr add dev $DEV 10.1.1.200/24
+	arp -s 10.1.1.100 52:54:00:d9:01:00
+}
+
+add_ip6vxlan_tunnel()
+{
+	#ip netns exec at_ns0 ip -4 addr del 172.16.1.100 dev veth0
+	ip netns exec at_ns0 ip -6 addr add ::11/96 dev veth0
+	ip netns exec at_ns0 ip link set dev veth0 up
+	#ip -4 addr del 172.16.1.200 dev veth1
+	ip -6 addr add dev veth1 ::22/96
+	ip link set dev veth1 up
+
+	# at_ns0 namespace
+	ip netns exec at_ns0 \
+		ip link add dev $DEV_NS type $TYPE id 22 dstport 4789 \
+		local ::11 remote ::22
+	ip netns exec at_ns0 ip addr add dev $DEV_NS 10.1.1.100/24
+	ip netns exec at_ns0 ip link set dev $DEV_NS up
+
+	# root namespace
+	ip link add dev $DEV type $TYPE external dstport 4789
+	ip addr add dev $DEV 10.1.1.200/24
+	ip link set dev $DEV up
+}
+
+add_geneve_tunnel()
+{
+	# at_ns0 namespace
+	ip netns exec at_ns0 \
+		ip link add dev $DEV_NS type $TYPE \
+		id 2 dstport 6081 remote 172.16.1.200
+	ip netns exec at_ns0 ip link set dev $DEV_NS up
+	ip netns exec at_ns0 ip addr add dev $DEV_NS 10.1.1.100/24
+
+	# root namespace
+	ip link add dev $DEV type $TYPE dstport 6081 external
+	ip link set dev $DEV up
+	ip addr add dev $DEV 10.1.1.200/24
+}
+
+add_ip6geneve_tunnel()
+{
+	ip netns exec at_ns0 ip addr add ::11/96 dev veth0
+	ip netns exec at_ns0 ip link set dev veth0 up
+	ip addr add dev veth1 ::22/96
+	ip link set dev veth1 up
+
+	# at_ns0 namespace
+	ip netns exec at_ns0 \
+		ip link add dev $DEV_NS type $TYPE id 22 \
+		remote ::22     # geneve has no local option
+	ip netns exec at_ns0 ip addr add dev $DEV_NS 10.1.1.100/24
+	ip netns exec at_ns0 ip link set dev $DEV_NS up
+
+	# root namespace
+	ip link add dev $DEV type $TYPE external
+	ip addr add dev $DEV 10.1.1.200/24
+	ip link set dev $DEV up
+}
+
+add_ipip_tunnel()
+{
+	# at_ns0 namespace
+	ip netns exec at_ns0 \
+		ip link add dev $DEV_NS type $TYPE \
+		local 172.16.1.100 remote 172.16.1.200
+	ip netns exec at_ns0 ip link set dev $DEV_NS up
+	ip netns exec at_ns0 ip addr add dev $DEV_NS 10.1.1.100/24
+
+	# root namespace
+	ip link add dev $DEV type $TYPE external
+	ip link set dev $DEV up
+	ip addr add dev $DEV 10.1.1.200/24
+}
+
+add_ipip6tnl_tunnel()
+{
+	ip netns exec at_ns0 ip addr add ::11/96 dev veth0
+	ip netns exec at_ns0 ip link set dev veth0 up
+	ip addr add dev veth1 ::22/96
+	ip link set dev veth1 up
+
+	# at_ns0 namespace
+	ip netns exec at_ns0 \
+		ip link add dev $DEV_NS type $TYPE \
+		local ::11 remote ::22
+	ip netns exec at_ns0 ip addr add dev $DEV_NS 10.1.1.100/24
+	ip netns exec at_ns0 ip link set dev $DEV_NS up
+
+	# root namespace
+	ip link add dev $DEV type $TYPE external
+	ip addr add dev $DEV 10.1.1.200/24
+	ip link set dev $DEV up
+}
+
+test_gre()
+{
+	TYPE=gretap
+	DEV_NS=gretap00
+	DEV=gretap11
+	ret=0
+
+	check $TYPE
+	config_device
+	add_gre_tunnel
+	attach_bpf $DEV gre_set_tunnel gre_get_tunnel
+	ping $PING_ARG 10.1.1.100
+	check_err $?
+	ip netns exec at_ns0 ping $PING_ARG 10.1.1.200
+	check_err $?
+	cleanup
+
+        if [ $ret -ne 0 ]; then
+                echo -e ${RED}"FAIL: $TYPE"${NC}
+                return 1
+        fi
+        echo -e ${GREEN}"PASS: $TYPE"${NC}
+}
+
+test_ip6gre()
+{
+	TYPE=ip6gre
+	DEV_NS=ip6gre00
+	DEV=ip6gre11
+	ret=0
+
+	check $TYPE
+	config_device
+	# reuse the ip6gretap function
+	add_ip6gretap_tunnel
+	attach_bpf $DEV ip6gretap_set_tunnel ip6gretap_get_tunnel
+	# underlay
+	ping6 $PING_ARG ::11
+	# overlay: ipv4 over ipv6
+	ip netns exec at_ns0 ping $PING_ARG 10.1.1.200
+	ping $PING_ARG 10.1.1.100
+	check_err $?
+	# overlay: ipv6 over ipv6
+	ip netns exec at_ns0 ping6 $PING_ARG fc80::200
+	check_err $?
+	cleanup
+
+        if [ $ret -ne 0 ]; then
+                echo -e ${RED}"FAIL: $TYPE"${NC}
+                return 1
+        fi
+        echo -e ${GREEN}"PASS: $TYPE"${NC}
+}
+
+test_ip6gretap()
+{
+	TYPE=ip6gretap
+	DEV_NS=ip6gretap00
+	DEV=ip6gretap11
+	ret=0
+
+	check $TYPE
+	config_device
+	add_ip6gretap_tunnel
+	attach_bpf $DEV ip6gretap_set_tunnel ip6gretap_get_tunnel
+	# underlay
+	ping6 $PING_ARG ::11
+	# overlay: ipv4 over ipv6
+	ip netns exec at_ns0 ping $PING_ARG 10.1.1.200
+	ping $PING_ARG 10.1.1.100
+	check_err $?
+	# overlay: ipv6 over ipv6
+	ip netns exec at_ns0 ping6 $PING_ARG fc80::200
+	check_err $?
+	cleanup
+
+	if [ $ret -ne 0 ]; then
+                echo -e ${RED}"FAIL: $TYPE"${NC}
+                return 1
+        fi
+        echo -e ${GREEN}"PASS: $TYPE"${NC}
+}
+
+test_erspan()
+{
+	TYPE=erspan
+	DEV_NS=erspan00
+	DEV=erspan11
+	ret=0
+
+	check $TYPE
+	config_device
+	add_erspan_tunnel $1
+	attach_bpf $DEV erspan_set_tunnel erspan_get_tunnel
+	ping $PING_ARG 10.1.1.100
+	check_err $?
+	ip netns exec at_ns0 ping $PING_ARG 10.1.1.200
+	check_err $?
+	cleanup
+
+	if [ $ret -ne 0 ]; then
+                echo -e ${RED}"FAIL: $TYPE"${NC}
+                return 1
+        fi
+        echo -e ${GREEN}"PASS: $TYPE"${NC}
+}
+
+test_ip6erspan()
+{
+	TYPE=ip6erspan
+	DEV_NS=ip6erspan00
+	DEV=ip6erspan11
+	ret=0
+
+	check $TYPE
+	config_device
+	add_ip6erspan_tunnel $1
+	attach_bpf $DEV ip4ip6erspan_set_tunnel ip4ip6erspan_get_tunnel
+	ping6 $PING_ARG ::11
+	ip netns exec at_ns0 ping $PING_ARG 10.1.1.200
+	check_err $?
+	cleanup
+
+	if [ $ret -ne 0 ]; then
+                echo -e ${RED}"FAIL: $TYPE"${NC}
+                return 1
+        fi
+        echo -e ${GREEN}"PASS: $TYPE"${NC}
+}
+
+test_vxlan()
+{
+	TYPE=vxlan
+	DEV_NS=vxlan00
+	DEV=vxlan11
+	ret=0
+
+	check $TYPE
+	config_device
+	add_vxlan_tunnel
+	attach_bpf $DEV vxlan_set_tunnel vxlan_get_tunnel
+	ping $PING_ARG 10.1.1.100
+	check_err $?
+	ip netns exec at_ns0 ping $PING_ARG 10.1.1.200
+	check_err $?
+	cleanup
+
+	if [ $ret -ne 0 ]; then
+                echo -e ${RED}"FAIL: $TYPE"${NC}
+                return 1
+        fi
+        echo -e ${GREEN}"PASS: $TYPE"${NC}
+}
+
+test_ip6vxlan()
+{
+	TYPE=vxlan
+	DEV_NS=ip6vxlan00
+	DEV=ip6vxlan11
+	ret=0
+
+	check $TYPE
+	config_device
+	add_ip6vxlan_tunnel
+	ip link set dev veth1 mtu 1500
+	attach_bpf $DEV ip6vxlan_set_tunnel ip6vxlan_get_tunnel
+	# underlay
+	ping6 $PING_ARG ::11
+	# ip4 over ip6
+	ping $PING_ARG 10.1.1.100
+	check_err $?
+	ip netns exec at_ns0 ping $PING_ARG 10.1.1.200
+	check_err $?
+	cleanup
+
+	if [ $ret -ne 0 ]; then
+                echo -e ${RED}"FAIL: ip6$TYPE"${NC}
+                return 1
+        fi
+        echo -e ${GREEN}"PASS: ip6$TYPE"${NC}
+}
+
+test_geneve()
+{
+	TYPE=geneve
+	DEV_NS=geneve00
+	DEV=geneve11
+	ret=0
+
+	check $TYPE
+	config_device
+	add_geneve_tunnel
+	attach_bpf $DEV geneve_set_tunnel geneve_get_tunnel
+	ping $PING_ARG 10.1.1.100
+	check_err $?
+	ip netns exec at_ns0 ping $PING_ARG 10.1.1.200
+	check_err $?
+	cleanup
+
+	if [ $ret -ne 0 ]; then
+                echo -e ${RED}"FAIL: $TYPE"${NC}
+                return 1
+        fi
+        echo -e ${GREEN}"PASS: $TYPE"${NC}
+}
+
+test_ip6geneve()
+{
+	TYPE=geneve
+	DEV_NS=ip6geneve00
+	DEV=ip6geneve11
+	ret=0
+
+	check $TYPE
+	config_device
+	add_ip6geneve_tunnel
+	attach_bpf $DEV ip6geneve_set_tunnel ip6geneve_get_tunnel
+	ping $PING_ARG 10.1.1.100
+	check_err $?
+	ip netns exec at_ns0 ping $PING_ARG 10.1.1.200
+	check_err $?
+	cleanup
+
+	if [ $ret -ne 0 ]; then
+                echo -e ${RED}"FAIL: ip6$TYPE"${NC}
+                return 1
+        fi
+        echo -e ${GREEN}"PASS: ip6$TYPE"${NC}
+}
+
+test_ipip()
+{
+	TYPE=ipip
+	DEV_NS=ipip00
+	DEV=ipip11
+	ret=0
+
+	check $TYPE
+	config_device
+	add_ipip_tunnel
+	ip link set dev veth1 mtu 1500
+	attach_bpf $DEV ipip_set_tunnel ipip_get_tunnel
+	ping $PING_ARG 10.1.1.100
+	check_err $?
+	ip netns exec at_ns0 ping $PING_ARG 10.1.1.200
+	check_err $?
+	cleanup
+
+	if [ $ret -ne 0 ]; then
+                echo -e ${RED}"FAIL: $TYPE"${NC}
+                return 1
+        fi
+        echo -e ${GREEN}"PASS: $TYPE"${NC}
+}
+
+test_ipip6()
+{
+	TYPE=ip6tnl
+	DEV_NS=ipip6tnl00
+	DEV=ipip6tnl11
+	ret=0
+
+	check $TYPE
+	config_device
+	add_ipip6tnl_tunnel
+	ip link set dev veth1 mtu 1500
+	attach_bpf $DEV ipip6_set_tunnel ipip6_get_tunnel
+	# underlay
+	ping6 $PING_ARG ::11
+	# ip4 over ip6
+	ping $PING_ARG 10.1.1.100
+	check_err $?
+	ip netns exec at_ns0 ping $PING_ARG 10.1.1.200
+	check_err $?
+	cleanup
+
+	if [ $ret -ne 0 ]; then
+                echo -e ${RED}"FAIL: $TYPE"${NC}
+                return 1
+        fi
+        echo -e ${GREEN}"PASS: $TYPE"${NC}
+}
+
+setup_xfrm_tunnel()
+{
+	auth=0x$(printf '1%.0s' {1..40})
+	enc=0x$(printf '2%.0s' {1..32})
+	spi_in_to_out=0x1
+	spi_out_to_in=0x2
+	# at_ns0 namespace
+	# at_ns0 -> root
+	ip netns exec at_ns0 \
+		ip xfrm state add src 172.16.1.100 dst 172.16.1.200 proto esp \
+			spi $spi_in_to_out reqid 1 mode tunnel \
+			auth-trunc 'hmac(sha1)' $auth 96 enc 'cbc(aes)' $enc
+	ip netns exec at_ns0 \
+		ip xfrm policy add src 10.1.1.100/32 dst 10.1.1.200/32 dir out \
+		tmpl src 172.16.1.100 dst 172.16.1.200 proto esp reqid 1 \
+		mode tunnel
+	# root -> at_ns0
+	ip netns exec at_ns0 \
+		ip xfrm state add src 172.16.1.200 dst 172.16.1.100 proto esp \
+			spi $spi_out_to_in reqid 2 mode tunnel \
+			auth-trunc 'hmac(sha1)' $auth 96 enc 'cbc(aes)' $enc
+	ip netns exec at_ns0 \
+		ip xfrm policy add src 10.1.1.200/32 dst 10.1.1.100/32 dir in \
+		tmpl src 172.16.1.200 dst 172.16.1.100 proto esp reqid 2 \
+		mode tunnel
+	# address & route
+	ip netns exec at_ns0 \
+		ip addr add dev veth0 10.1.1.100/32
+	ip netns exec at_ns0 \
+		ip route add 10.1.1.200 dev veth0 via 172.16.1.200 \
+			src 10.1.1.100
+
+	# root namespace
+	# at_ns0 -> root
+	ip xfrm state add src 172.16.1.100 dst 172.16.1.200 proto esp \
+		spi $spi_in_to_out reqid 1 mode tunnel \
+		auth-trunc 'hmac(sha1)' $auth 96  enc 'cbc(aes)' $enc
+	ip xfrm policy add src 10.1.1.100/32 dst 10.1.1.200/32 dir in \
+		tmpl src 172.16.1.100 dst 172.16.1.200 proto esp reqid 1 \
+		mode tunnel
+	# root -> at_ns0
+	ip xfrm state add src 172.16.1.200 dst 172.16.1.100 proto esp \
+		spi $spi_out_to_in reqid 2 mode tunnel \
+		auth-trunc 'hmac(sha1)' $auth 96  enc 'cbc(aes)' $enc
+	ip xfrm policy add src 10.1.1.200/32 dst 10.1.1.100/32 dir out \
+		tmpl src 172.16.1.200 dst 172.16.1.100 proto esp reqid 2 \
+		mode tunnel
+	# address & route
+	ip addr add dev veth1 10.1.1.200/32
+	ip route add 10.1.1.100 dev veth1 via 172.16.1.100 src 10.1.1.200
+}
+
+test_xfrm_tunnel()
+{
+	config_device
+        #tcpdump -nei veth1 ip &
+	output=$(mktemp)
+	cat /sys/kernel/debug/tracing/trace_pipe | tee $output &
+        setup_xfrm_tunnel
+	tc qdisc add dev veth1 clsact
+	tc filter add dev veth1 proto ip ingress bpf da obj test_tunnel_kern.o \
+		sec xfrm_get_state
+	ip netns exec at_ns0 ping $PING_ARG 10.1.1.200
+	sleep 1
+	grep "reqid 1" $output
+	check_err $?
+	grep "spi 0x1" $output
+	check_err $?
+	grep "remote ip 0xac100164" $output
+	check_err $?
+	cleanup
+
+	if [ $ret -ne 0 ]; then
+                echo -e ${RED}"FAIL: xfrm tunnel"${NC}
+                return 1
+        fi
+        echo -e ${GREEN}"PASS: xfrm tunnel"${NC}
+}
+
+attach_bpf()
+{
+	DEV=$1
+	SET=$2
+	GET=$3
+	tc qdisc add dev $DEV clsact
+	tc filter add dev $DEV egress bpf da obj test_tunnel_kern.o sec $SET
+	tc filter add dev $DEV ingress bpf da obj test_tunnel_kern.o sec $GET
+}
+
+cleanup()
+{
+	ip netns delete at_ns0 2> /dev/null
+	ip link del veth1 2> /dev/null
+	ip link del ipip11 2> /dev/null
+	ip link del ipip6tnl11 2> /dev/null
+	ip link del gretap11 2> /dev/null
+	ip link del ip6gre11 2> /dev/null
+	ip link del ip6gretap11 2> /dev/null
+	ip link del vxlan11 2> /dev/null
+	ip link del ip6vxlan11 2> /dev/null
+	ip link del geneve11 2> /dev/null
+	ip link del ip6geneve11 2> /dev/null
+	ip link del erspan11 2> /dev/null
+	ip link del ip6erspan11 2> /dev/null
+}
+
+cleanup_exit()
+{
+	echo "CATCH SIGKILL or SIGINT, cleanup and exit"
+	cleanup
+	exit 0
+}
+
+check()
+{
+	ip link help $1 2>&1 | grep -q "^Usage:"
+	if [ $? -ne 0 ];then
+		echo "SKIP $1: iproute2 not support"
+	cleanup
+	return 1
+	fi
+}
+
+enable_debug()
+{
+	echo 'file ip_gre.c +p' > /sys/kernel/debug/dynamic_debug/control
+	echo 'file ip6_gre.c +p' > /sys/kernel/debug/dynamic_debug/control
+	echo 'file vxlan.c +p' > /sys/kernel/debug/dynamic_debug/control
+	echo 'file geneve.c +p' > /sys/kernel/debug/dynamic_debug/control
+	echo 'file ipip.c +p' > /sys/kernel/debug/dynamic_debug/control
+}
+
+check_err()
+{
+	if [ $ret -eq 0 ]; then
+		ret=$1
+	fi
+}
+
+bpf_tunnel_test()
+{
+	echo "Testing GRE tunnel..."
+	test_gre
+	echo "Testing IP6GRE tunnel..."
+	test_ip6gre
+	echo "Testing IP6GRETAP tunnel..."
+	test_ip6gretap
+	echo "Testing ERSPAN tunnel..."
+	test_erspan v2
+	echo "Testing IP6ERSPAN tunnel..."
+	test_ip6erspan v2
+	echo "Testing VXLAN tunnel..."
+	test_vxlan
+	echo "Testing IP6VXLAN tunnel..."
+	test_ip6vxlan
+	echo "Testing GENEVE tunnel..."
+	test_geneve
+	echo "Testing IP6GENEVE tunnel..."
+	test_ip6geneve
+	echo "Testing IPIP tunnel..."
+	test_ipip
+	echo "Testing IPIP6 tunnel..."
+	test_ipip6
+	echo "Testing IPSec tunnel..."
+	test_xfrm_tunnel
+}
+
+trap cleanup 0 3 6
+trap cleanup_exit 2 9
+
+cleanup
+bpf_tunnel_test
+
+exit 0
diff --git a/samples/bpf/tcbpf2_kern.c b/tools/testing/selftests/bpf/test_tunnel_kern.c
index 9a8db7bd6db4..504df69c83df 100644
--- a/samples/bpf/tcbpf2_kern.c
+++ b/tools/testing/selftests/bpf/test_tunnel_kern.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 /* Copyright (c) 2016 VMware
  * Copyright (c) 2016 Facebook
  *
@@ -5,39 +6,41 @@
  * modify it under the terms of version 2 of the GNU General Public
  * License as published by the Free Software Foundation.
  */
-#define KBUILD_MODNAME "foo"
-#include <uapi/linux/bpf.h>
-#include <uapi/linux/if_ether.h>
-#include <uapi/linux/if_packet.h>
-#include <uapi/linux/ip.h>
-#include <uapi/linux/ipv6.h>
-#include <uapi/linux/in.h>
-#include <uapi/linux/tcp.h>
-#include <uapi/linux/filter.h>
-#include <uapi/linux/pkt_cls.h>
-#include <uapi/linux/erspan.h>
-#include <net/ipv6.h>
+#include <stddef.h>
+#include <string.h>
+#include <arpa/inet.h>
+#include <linux/bpf.h>
+#include <linux/if_ether.h>
+#include <linux/if_packet.h>
+#include <linux/ip.h>
+#include <linux/ipv6.h>
+#include <linux/types.h>
+#include <linux/tcp.h>
+#include <linux/socket.h>
+#include <linux/pkt_cls.h>
+#include <linux/erspan.h>
 #include "bpf_helpers.h"
 #include "bpf_endian.h"
 
-#define _htonl __builtin_bswap32
 #define ERROR(ret) do {\
 		char fmt[] = "ERROR line:%d ret:%d\n";\
 		bpf_trace_printk(fmt, sizeof(fmt), __LINE__, ret); \
-	} while(0)
+	} while (0)
+
+int _version SEC("version") = 1;
 
 struct geneve_opt {
 	__be16	opt_class;
-	u8	type;
-	u8	length:5;
-	u8	r3:1;
-	u8	r2:1;
-	u8	r1:1;
-	u8	opt_data[8]; /* hard-coded to 8 byte */
+	__u8	type;
+	__u8	length:5;
+	__u8	r3:1;
+	__u8	r2:1;
+	__u8	r1:1;
+	__u8	opt_data[8]; /* hard-coded to 8 byte */
 };
 
 struct vxlan_metadata {
-	u32     gbp;
+	__u32     gbp;
 };
 
 SEC("gre_set_tunnel")
@@ -86,7 +89,7 @@ int _ip6gretap_set_tunnel(struct __sk_buff *skb)
 	int ret;
 
 	__builtin_memset(&key, 0x0, sizeof(key));
-	key.remote_ipv6[3] = _htonl(0x11); /* ::11 */
+	key.remote_ipv6[3] = bpf_htonl(0x11); /* ::11 */
 	key.tunnel_id = 2;
 	key.tunnel_tos = 0;
 	key.tunnel_ttl = 64;
@@ -136,7 +139,8 @@ int _erspan_set_tunnel(struct __sk_buff *skb)
 	key.tunnel_tos = 0;
 	key.tunnel_ttl = 64;
 
-	ret = bpf_skb_set_tunnel_key(skb, &key, sizeof(key), BPF_F_ZERO_CSUM_TX);
+	ret = bpf_skb_set_tunnel_key(skb, &key, sizeof(key),
+				     BPF_F_ZERO_CSUM_TX);
 	if (ret < 0) {
 		ERROR(ret);
 		return TC_ACT_SHOT;
@@ -147,8 +151,8 @@ int _erspan_set_tunnel(struct __sk_buff *skb)
 	md.version = 1;
 	md.u.index = bpf_htonl(123);
 #else
-	u8 direction = 1;
-	u8 hwid = 7;
+	__u8 direction = 1;
+	__u8 hwid = 7;
 
 	md.version = 2;
 	md.u.md2.dir = direction;
@@ -171,7 +175,7 @@ int _erspan_get_tunnel(struct __sk_buff *skb)
 	char fmt[] = "key %d remote ip 0x%x erspan version %d\n";
 	struct bpf_tunnel_key key;
 	struct erspan_metadata md;
-	u32 index;
+	__u32 index;
 	int ret;
 
 	ret = bpf_skb_get_tunnel_key(skb, &key, sizeof(key), 0);
@@ -214,7 +218,7 @@ int _ip4ip6erspan_set_tunnel(struct __sk_buff *skb)
 	int ret;
 
 	__builtin_memset(&key, 0x0, sizeof(key));
-	key.remote_ipv6[3] = _htonl(0x11);
+	key.remote_ipv6[3] = bpf_htonl(0x11);
 	key.tunnel_id = 2;
 	key.tunnel_tos = 0;
 	key.tunnel_ttl = 64;
@@ -229,11 +233,11 @@ int _ip4ip6erspan_set_tunnel(struct __sk_buff *skb)
 	__builtin_memset(&md, 0, sizeof(md));
 
 #ifdef ERSPAN_V1
-	md.u.index = htonl(123);
+	md.u.index = bpf_htonl(123);
 	md.version = 1;
 #else
-	u8 direction = 0;
-	u8 hwid = 17;
+	__u8 direction = 0;
+	__u8 hwid = 17;
 
 	md.version = 2;
 	md.u.md2.dir = direction;
@@ -256,10 +260,11 @@ int _ip4ip6erspan_get_tunnel(struct __sk_buff *skb)
 	char fmt[] = "ip6erspan get key %d remote ip6 ::%x erspan version %d\n";
 	struct bpf_tunnel_key key;
 	struct erspan_metadata md;
-	u32 index;
+	__u32 index;
 	int ret;
 
-	ret = bpf_skb_get_tunnel_key(skb, &key, sizeof(key), BPF_F_TUNINFO_IPV6);
+	ret = bpf_skb_get_tunnel_key(skb, &key, sizeof(key),
+				     BPF_F_TUNINFO_IPV6);
 	if (ret < 0) {
 		ERROR(ret);
 		return TC_ACT_SHOT;
@@ -304,7 +309,8 @@ int _vxlan_set_tunnel(struct __sk_buff *skb)
 	key.tunnel_tos = 0;
 	key.tunnel_ttl = 64;
 
-	ret = bpf_skb_set_tunnel_key(skb, &key, sizeof(key), BPF_F_ZERO_CSUM_TX);
+	ret = bpf_skb_set_tunnel_key(skb, &key, sizeof(key),
+				     BPF_F_ZERO_CSUM_TX);
 	if (ret < 0) {
 		ERROR(ret);
 		return TC_ACT_SHOT;
@@ -346,6 +352,48 @@ int _vxlan_get_tunnel(struct __sk_buff *skb)
 	return TC_ACT_OK;
 }
 
+SEC("ip6vxlan_set_tunnel")
+int _ip6vxlan_set_tunnel(struct __sk_buff *skb)
+{
+	struct bpf_tunnel_key key;
+	int ret;
+
+	__builtin_memset(&key, 0x0, sizeof(key));
+	key.remote_ipv6[3] = bpf_htonl(0x11); /* ::11 */
+	key.tunnel_id = 22;
+	key.tunnel_tos = 0;
+	key.tunnel_ttl = 64;
+
+	ret = bpf_skb_set_tunnel_key(skb, &key, sizeof(key),
+				     BPF_F_TUNINFO_IPV6);
+	if (ret < 0) {
+		ERROR(ret);
+		return TC_ACT_SHOT;
+	}
+
+	return TC_ACT_OK;
+}
+
+SEC("ip6vxlan_get_tunnel")
+int _ip6vxlan_get_tunnel(struct __sk_buff *skb)
+{
+	char fmt[] = "key %d remote ip6 ::%x label %x\n";
+	struct bpf_tunnel_key key;
+	int ret;
+
+	ret = bpf_skb_get_tunnel_key(skb, &key, sizeof(key),
+				     BPF_F_TUNINFO_IPV6);
+	if (ret < 0) {
+		ERROR(ret);
+		return TC_ACT_SHOT;
+	}
+
+	bpf_trace_printk(fmt, sizeof(fmt),
+			 key.tunnel_id, key.remote_ipv6[3], key.tunnel_label);
+
+	return TC_ACT_OK;
+}
+
 SEC("geneve_set_tunnel")
 int _geneve_set_tunnel(struct __sk_buff *skb)
 {
@@ -360,15 +408,16 @@ int _geneve_set_tunnel(struct __sk_buff *skb)
 	key.tunnel_ttl = 64;
 
 	__builtin_memset(&gopt, 0x0, sizeof(gopt));
-	gopt.opt_class = 0x102; /* Open Virtual Networking (OVN) */
+	gopt.opt_class = bpf_htons(0x102); /* Open Virtual Networking (OVN) */
 	gopt.type = 0x08;
 	gopt.r1 = 0;
 	gopt.r2 = 0;
 	gopt.r3 = 0;
 	gopt.length = 2; /* 4-byte multiple */
-	*(int *) &gopt.opt_data = 0xdeadbeef;
+	*(int *) &gopt.opt_data = bpf_htonl(0xdeadbeef);
 
-	ret = bpf_skb_set_tunnel_key(skb, &key, sizeof(key), BPF_F_ZERO_CSUM_TX);
+	ret = bpf_skb_set_tunnel_key(skb, &key, sizeof(key),
+				     BPF_F_ZERO_CSUM_TX);
 	if (ret < 0) {
 		ERROR(ret);
 		return TC_ACT_SHOT;
@@ -408,6 +457,71 @@ int _geneve_get_tunnel(struct __sk_buff *skb)
 	return TC_ACT_OK;
 }
 
+SEC("ip6geneve_set_tunnel")
+int _ip6geneve_set_tunnel(struct __sk_buff *skb)
+{
+	struct bpf_tunnel_key key;
+	struct geneve_opt gopt;
+	int ret;
+
+	__builtin_memset(&key, 0x0, sizeof(key));
+	key.remote_ipv6[3] = bpf_htonl(0x11); /* ::11 */
+	key.tunnel_id = 22;
+	key.tunnel_tos = 0;
+	key.tunnel_ttl = 64;
+
+	ret = bpf_skb_set_tunnel_key(skb, &key, sizeof(key),
+				     BPF_F_TUNINFO_IPV6);
+	if (ret < 0) {
+		ERROR(ret);
+		return TC_ACT_SHOT;
+	}
+
+	__builtin_memset(&gopt, 0x0, sizeof(gopt));
+	gopt.opt_class = bpf_htons(0x102); /* Open Virtual Networking (OVN) */
+	gopt.type = 0x08;
+	gopt.r1 = 0;
+	gopt.r2 = 0;
+	gopt.r3 = 0;
+	gopt.length = 2; /* 4-byte multiple */
+	*(int *) &gopt.opt_data = bpf_htonl(0xfeedbeef);
+
+	ret = bpf_skb_set_tunnel_opt(skb, &gopt, sizeof(gopt));
+	if (ret < 0) {
+		ERROR(ret);
+		return TC_ACT_SHOT;
+	}
+
+	return TC_ACT_OK;
+}
+
+SEC("ip6geneve_get_tunnel")
+int _ip6geneve_get_tunnel(struct __sk_buff *skb)
+{
+	char fmt[] = "key %d remote ip 0x%x geneve class 0x%x\n";
+	struct bpf_tunnel_key key;
+	struct geneve_opt gopt;
+	int ret;
+
+	ret = bpf_skb_get_tunnel_key(skb, &key, sizeof(key),
+				     BPF_F_TUNINFO_IPV6);
+	if (ret < 0) {
+		ERROR(ret);
+		return TC_ACT_SHOT;
+	}
+
+	ret = bpf_skb_get_tunnel_opt(skb, &gopt, sizeof(gopt));
+	if (ret < 0) {
+		ERROR(ret);
+		return TC_ACT_SHOT;
+	}
+
+	bpf_trace_printk(fmt, sizeof(fmt),
+			key.tunnel_id, key.remote_ipv4, gopt.opt_class);
+
+	return TC_ACT_OK;
+}
+
 SEC("ipip_set_tunnel")
 int _ipip_set_tunnel(struct __sk_buff *skb)
 {
@@ -431,9 +545,9 @@ int _ipip_set_tunnel(struct __sk_buff *skb)
 		if (iph->protocol != IPPROTO_TCP || iph->ihl != 5)
 			return TC_ACT_SHOT;
 
-		if (tcp->dest == htons(5200))
+		if (tcp->dest == bpf_htons(5200))
 			key.remote_ipv4 = 0xac100164; /* 172.16.1.100 */
-		else if (tcp->dest == htons(5201))
+		else if (tcp->dest == bpf_htons(5201))
 			key.remote_ipv4 = 0xac100165; /* 172.16.1.101 */
 		else
 			return TC_ACT_SHOT;
@@ -481,28 +595,12 @@ int _ipip6_set_tunnel(struct __sk_buff *skb)
 		return TC_ACT_SHOT;
 	}
 
-	key.remote_ipv6[0] = _htonl(0x2401db00);
+	__builtin_memset(&key, 0x0, sizeof(key));
+	key.remote_ipv6[3] = bpf_htonl(0x11); /* ::11 */
 	key.tunnel_ttl = 64;
 
-	if (iph->protocol == IPPROTO_ICMP) {
-		key.remote_ipv6[3] = _htonl(1);
-	} else {
-		if (iph->protocol != IPPROTO_TCP || iph->ihl != 5) {
-			ERROR(iph->protocol);
-			return TC_ACT_SHOT;
-		}
-
-		if (tcp->dest == htons(5200)) {
-			key.remote_ipv6[3] = _htonl(1);
-		} else if (tcp->dest == htons(5201)) {
-			key.remote_ipv6[3] = _htonl(2);
-		} else {
-			ERROR(tcp->dest);
-			return TC_ACT_SHOT;
-		}
-	}
-
-	ret = bpf_skb_set_tunnel_key(skb, &key, sizeof(key), BPF_F_TUNINFO_IPV6);
+	ret = bpf_skb_set_tunnel_key(skb, &key, sizeof(key),
+				     BPF_F_TUNINFO_IPV6);
 	if (ret < 0) {
 		ERROR(ret);
 		return TC_ACT_SHOT;
@@ -518,14 +616,15 @@ int _ipip6_get_tunnel(struct __sk_buff *skb)
 	struct bpf_tunnel_key key;
 	char fmt[] = "remote ip6 %x::%x\n";
 
-	ret = bpf_skb_get_tunnel_key(skb, &key, sizeof(key), BPF_F_TUNINFO_IPV6);
+	ret = bpf_skb_get_tunnel_key(skb, &key, sizeof(key),
+				     BPF_F_TUNINFO_IPV6);
 	if (ret < 0) {
 		ERROR(ret);
 		return TC_ACT_SHOT;
 	}
 
-	bpf_trace_printk(fmt, sizeof(fmt), _htonl(key.remote_ipv6[0]),
-			 _htonl(key.remote_ipv6[3]));
+	bpf_trace_printk(fmt, sizeof(fmt), bpf_htonl(key.remote_ipv6[0]),
+			 bpf_htonl(key.remote_ipv6[3]));
 	return TC_ACT_OK;
 }
 
@@ -545,28 +644,29 @@ int _ip6ip6_set_tunnel(struct __sk_buff *skb)
 		return TC_ACT_SHOT;
 	}
 
-	key.remote_ipv6[0] = _htonl(0x2401db00);
+	key.remote_ipv6[0] = bpf_htonl(0x2401db00);
 	key.tunnel_ttl = 64;
 
-	if (iph->nexthdr == NEXTHDR_ICMP) {
-		key.remote_ipv6[3] = _htonl(1);
+	if (iph->nexthdr == 58 /* NEXTHDR_ICMP */) {
+		key.remote_ipv6[3] = bpf_htonl(1);
 	} else {
-		if (iph->nexthdr != NEXTHDR_TCP) {
+		if (iph->nexthdr != 6 /* NEXTHDR_TCP */) {
 			ERROR(iph->nexthdr);
 			return TC_ACT_SHOT;
 		}
 
-		if (tcp->dest == htons(5200)) {
-			key.remote_ipv6[3] = _htonl(1);
-		} else if (tcp->dest == htons(5201)) {
-			key.remote_ipv6[3] = _htonl(2);
+		if (tcp->dest == bpf_htons(5200)) {
+			key.remote_ipv6[3] = bpf_htonl(1);
+		} else if (tcp->dest == bpf_htons(5201)) {
+			key.remote_ipv6[3] = bpf_htonl(2);
 		} else {
 			ERROR(tcp->dest);
 			return TC_ACT_SHOT;
 		}
 	}
 
-	ret = bpf_skb_set_tunnel_key(skb, &key, sizeof(key), BPF_F_TUNINFO_IPV6);
+	ret = bpf_skb_set_tunnel_key(skb, &key, sizeof(key),
+				     BPF_F_TUNINFO_IPV6);
 	if (ret < 0) {
 		ERROR(ret);
 		return TC_ACT_SHOT;
@@ -582,14 +682,31 @@ int _ip6ip6_get_tunnel(struct __sk_buff *skb)
 	struct bpf_tunnel_key key;
 	char fmt[] = "remote ip6 %x::%x\n";
 
-	ret = bpf_skb_get_tunnel_key(skb, &key, sizeof(key), BPF_F_TUNINFO_IPV6);
+	ret = bpf_skb_get_tunnel_key(skb, &key, sizeof(key),
+				     BPF_F_TUNINFO_IPV6);
 	if (ret < 0) {
 		ERROR(ret);
 		return TC_ACT_SHOT;
 	}
 
-	bpf_trace_printk(fmt, sizeof(fmt), _htonl(key.remote_ipv6[0]),
-			 _htonl(key.remote_ipv6[3]));
+	bpf_trace_printk(fmt, sizeof(fmt), bpf_htonl(key.remote_ipv6[0]),
+			 bpf_htonl(key.remote_ipv6[3]));
+	return TC_ACT_OK;
+}
+
+SEC("xfrm_get_state")
+int _xfrm_get_state(struct __sk_buff *skb)
+{
+	struct bpf_xfrm_state x;
+	char fmt[] = "reqid %d spi 0x%x remote ip 0x%x\n";
+	int ret;
+
+	ret = bpf_skb_get_xfrm_state(skb, 0, &x, sizeof(x), 0);
+	if (ret < 0)
+		return TC_ACT_OK;
+
+	bpf_trace_printk(fmt, sizeof(fmt), x.reqid, bpf_ntohl(x.spi),
+			 bpf_ntohl(x.remote_ipv4));
 	return TC_ACT_OK;
 }
 
diff --git a/tools/testing/selftests/bpf/test_verifier.c b/tools/testing/selftests/bpf/test_verifier.c
index 3e7718b1a9ae..165e9ddfa446 100644
--- a/tools/testing/selftests/bpf/test_verifier.c
+++ b/tools/testing/selftests/bpf/test_verifier.c
@@ -64,6 +64,7 @@ struct bpf_test {
 	struct bpf_insn	insns[MAX_INSNS];
 	int fixup_map1[MAX_FIXUPS];
 	int fixup_map2[MAX_FIXUPS];
+	int fixup_map3[MAX_FIXUPS];
 	int fixup_prog[MAX_FIXUPS];
 	int fixup_map_in_map[MAX_FIXUPS];
 	const char *errstr;
@@ -88,6 +89,11 @@ struct test_val {
 	int foo[MAX_ENTRIES];
 };
 
+struct other_val {
+	long long foo;
+	long long bar;
+};
+
 static struct bpf_test tests[] = {
 	{
 		"add+sub+mul",
@@ -5594,6 +5600,257 @@ static struct bpf_test tests[] = {
 		.prog_type = BPF_PROG_TYPE_TRACEPOINT,
 	},
 	{
+		"map lookup helper access to map",
+		.insns = {
+			BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
+			BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8),
+			BPF_ST_MEM(BPF_DW, BPF_REG_2, 0, 0),
+			BPF_LD_MAP_FD(BPF_REG_1, 0),
+			BPF_EMIT_CALL(BPF_FUNC_map_lookup_elem),
+			BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 4),
+			BPF_MOV64_REG(BPF_REG_2, BPF_REG_0),
+			BPF_LD_MAP_FD(BPF_REG_1, 0),
+			BPF_EMIT_CALL(BPF_FUNC_map_lookup_elem),
+			BPF_EXIT_INSN(),
+		},
+		.fixup_map3 = { 3, 8 },
+		.result = ACCEPT,
+		.prog_type = BPF_PROG_TYPE_TRACEPOINT,
+	},
+	{
+		"map update helper access to map",
+		.insns = {
+			BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
+			BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8),
+			BPF_ST_MEM(BPF_DW, BPF_REG_2, 0, 0),
+			BPF_LD_MAP_FD(BPF_REG_1, 0),
+			BPF_EMIT_CALL(BPF_FUNC_map_lookup_elem),
+			BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 6),
+			BPF_MOV64_IMM(BPF_REG_4, 0),
+			BPF_MOV64_REG(BPF_REG_3, BPF_REG_0),
+			BPF_MOV64_REG(BPF_REG_2, BPF_REG_0),
+			BPF_LD_MAP_FD(BPF_REG_1, 0),
+			BPF_EMIT_CALL(BPF_FUNC_map_update_elem),
+			BPF_EXIT_INSN(),
+		},
+		.fixup_map3 = { 3, 10 },
+		.result = ACCEPT,
+		.prog_type = BPF_PROG_TYPE_TRACEPOINT,
+	},
+	{
+		"map update helper access to map: wrong size",
+		.insns = {
+			BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
+			BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8),
+			BPF_ST_MEM(BPF_DW, BPF_REG_2, 0, 0),
+			BPF_LD_MAP_FD(BPF_REG_1, 0),
+			BPF_EMIT_CALL(BPF_FUNC_map_lookup_elem),
+			BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 6),
+			BPF_MOV64_IMM(BPF_REG_4, 0),
+			BPF_MOV64_REG(BPF_REG_3, BPF_REG_0),
+			BPF_MOV64_REG(BPF_REG_2, BPF_REG_0),
+			BPF_LD_MAP_FD(BPF_REG_1, 0),
+			BPF_EMIT_CALL(BPF_FUNC_map_update_elem),
+			BPF_EXIT_INSN(),
+		},
+		.fixup_map1 = { 3 },
+		.fixup_map3 = { 10 },
+		.result = REJECT,
+		.errstr = "invalid access to map value, value_size=8 off=0 size=16",
+		.prog_type = BPF_PROG_TYPE_TRACEPOINT,
+	},
+	{
+		"map helper access to adjusted map (via const imm)",
+		.insns = {
+			BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
+			BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8),
+			BPF_ST_MEM(BPF_DW, BPF_REG_2, 0, 0),
+			BPF_LD_MAP_FD(BPF_REG_1, 0),
+			BPF_EMIT_CALL(BPF_FUNC_map_lookup_elem),
+			BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 5),
+			BPF_MOV64_REG(BPF_REG_2, BPF_REG_0),
+			BPF_ALU64_IMM(BPF_ADD, BPF_REG_2,
+				      offsetof(struct other_val, bar)),
+			BPF_LD_MAP_FD(BPF_REG_1, 0),
+			BPF_EMIT_CALL(BPF_FUNC_map_lookup_elem),
+			BPF_EXIT_INSN(),
+		},
+		.fixup_map3 = { 3, 9 },
+		.result = ACCEPT,
+		.prog_type = BPF_PROG_TYPE_TRACEPOINT,
+	},
+	{
+		"map helper access to adjusted map (via const imm): out-of-bound 1",
+		.insns = {
+			BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
+			BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8),
+			BPF_ST_MEM(BPF_DW, BPF_REG_2, 0, 0),
+			BPF_LD_MAP_FD(BPF_REG_1, 0),
+			BPF_EMIT_CALL(BPF_FUNC_map_lookup_elem),
+			BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 5),
+			BPF_MOV64_REG(BPF_REG_2, BPF_REG_0),
+			BPF_ALU64_IMM(BPF_ADD, BPF_REG_2,
+				      sizeof(struct other_val) - 4),
+			BPF_LD_MAP_FD(BPF_REG_1, 0),
+			BPF_EMIT_CALL(BPF_FUNC_map_lookup_elem),
+			BPF_EXIT_INSN(),
+		},
+		.fixup_map3 = { 3, 9 },
+		.result = REJECT,
+		.errstr = "invalid access to map value, value_size=16 off=12 size=8",
+		.prog_type = BPF_PROG_TYPE_TRACEPOINT,
+	},
+	{
+		"map helper access to adjusted map (via const imm): out-of-bound 2",
+		.insns = {
+			BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
+			BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8),
+			BPF_ST_MEM(BPF_DW, BPF_REG_2, 0, 0),
+			BPF_LD_MAP_FD(BPF_REG_1, 0),
+			BPF_EMIT_CALL(BPF_FUNC_map_lookup_elem),
+			BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 5),
+			BPF_MOV64_REG(BPF_REG_2, BPF_REG_0),
+			BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -4),
+			BPF_LD_MAP_FD(BPF_REG_1, 0),
+			BPF_EMIT_CALL(BPF_FUNC_map_lookup_elem),
+			BPF_EXIT_INSN(),
+		},
+		.fixup_map3 = { 3, 9 },
+		.result = REJECT,
+		.errstr = "invalid access to map value, value_size=16 off=-4 size=8",
+		.prog_type = BPF_PROG_TYPE_TRACEPOINT,
+	},
+	{
+		"map helper access to adjusted map (via const reg)",
+		.insns = {
+			BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
+			BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8),
+			BPF_ST_MEM(BPF_DW, BPF_REG_2, 0, 0),
+			BPF_LD_MAP_FD(BPF_REG_1, 0),
+			BPF_EMIT_CALL(BPF_FUNC_map_lookup_elem),
+			BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 6),
+			BPF_MOV64_REG(BPF_REG_2, BPF_REG_0),
+			BPF_MOV64_IMM(BPF_REG_3,
+				      offsetof(struct other_val, bar)),
+			BPF_ALU64_REG(BPF_ADD, BPF_REG_2, BPF_REG_3),
+			BPF_LD_MAP_FD(BPF_REG_1, 0),
+			BPF_EMIT_CALL(BPF_FUNC_map_lookup_elem),
+			BPF_EXIT_INSN(),
+		},
+		.fixup_map3 = { 3, 10 },
+		.result = ACCEPT,
+		.prog_type = BPF_PROG_TYPE_TRACEPOINT,
+	},
+	{
+		"map helper access to adjusted map (via const reg): out-of-bound 1",
+		.insns = {
+			BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
+			BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8),
+			BPF_ST_MEM(BPF_DW, BPF_REG_2, 0, 0),
+			BPF_LD_MAP_FD(BPF_REG_1, 0),
+			BPF_EMIT_CALL(BPF_FUNC_map_lookup_elem),
+			BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 6),
+			BPF_MOV64_REG(BPF_REG_2, BPF_REG_0),
+			BPF_MOV64_IMM(BPF_REG_3,
+				      sizeof(struct other_val) - 4),
+			BPF_ALU64_REG(BPF_ADD, BPF_REG_2, BPF_REG_3),
+			BPF_LD_MAP_FD(BPF_REG_1, 0),
+			BPF_EMIT_CALL(BPF_FUNC_map_lookup_elem),
+			BPF_EXIT_INSN(),
+		},
+		.fixup_map3 = { 3, 10 },
+		.result = REJECT,
+		.errstr = "invalid access to map value, value_size=16 off=12 size=8",
+		.prog_type = BPF_PROG_TYPE_TRACEPOINT,
+	},
+	{
+		"map helper access to adjusted map (via const reg): out-of-bound 2",
+		.insns = {
+			BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
+			BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8),
+			BPF_ST_MEM(BPF_DW, BPF_REG_2, 0, 0),
+			BPF_LD_MAP_FD(BPF_REG_1, 0),
+			BPF_EMIT_CALL(BPF_FUNC_map_lookup_elem),
+			BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 6),
+			BPF_MOV64_REG(BPF_REG_2, BPF_REG_0),
+			BPF_MOV64_IMM(BPF_REG_3, -4),
+			BPF_ALU64_REG(BPF_ADD, BPF_REG_2, BPF_REG_3),
+			BPF_LD_MAP_FD(BPF_REG_1, 0),
+			BPF_EMIT_CALL(BPF_FUNC_map_lookup_elem),
+			BPF_EXIT_INSN(),
+		},
+		.fixup_map3 = { 3, 10 },
+		.result = REJECT,
+		.errstr = "invalid access to map value, value_size=16 off=-4 size=8",
+		.prog_type = BPF_PROG_TYPE_TRACEPOINT,
+	},
+	{
+		"map helper access to adjusted map (via variable)",
+		.insns = {
+			BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
+			BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8),
+			BPF_ST_MEM(BPF_DW, BPF_REG_2, 0, 0),
+			BPF_LD_MAP_FD(BPF_REG_1, 0),
+			BPF_EMIT_CALL(BPF_FUNC_map_lookup_elem),
+			BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 7),
+			BPF_MOV64_REG(BPF_REG_2, BPF_REG_0),
+			BPF_LDX_MEM(BPF_W, BPF_REG_3, BPF_REG_0, 0),
+			BPF_JMP_IMM(BPF_JGT, BPF_REG_3,
+				    offsetof(struct other_val, bar), 4),
+			BPF_ALU64_REG(BPF_ADD, BPF_REG_2, BPF_REG_3),
+			BPF_LD_MAP_FD(BPF_REG_1, 0),
+			BPF_EMIT_CALL(BPF_FUNC_map_lookup_elem),
+			BPF_EXIT_INSN(),
+		},
+		.fixup_map3 = { 3, 11 },
+		.result = ACCEPT,
+		.prog_type = BPF_PROG_TYPE_TRACEPOINT,
+	},
+	{
+		"map helper access to adjusted map (via variable): no max check",
+		.insns = {
+			BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
+			BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8),
+			BPF_ST_MEM(BPF_DW, BPF_REG_2, 0, 0),
+			BPF_LD_MAP_FD(BPF_REG_1, 0),
+			BPF_EMIT_CALL(BPF_FUNC_map_lookup_elem),
+			BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 6),
+			BPF_MOV64_REG(BPF_REG_2, BPF_REG_0),
+			BPF_LDX_MEM(BPF_W, BPF_REG_3, BPF_REG_0, 0),
+			BPF_ALU64_REG(BPF_ADD, BPF_REG_2, BPF_REG_3),
+			BPF_LD_MAP_FD(BPF_REG_1, 0),
+			BPF_EMIT_CALL(BPF_FUNC_map_lookup_elem),
+			BPF_EXIT_INSN(),
+		},
+		.fixup_map3 = { 3, 10 },
+		.result = REJECT,
+		.errstr = "R2 unbounded memory access, make sure to bounds check any array access into a map",
+		.prog_type = BPF_PROG_TYPE_TRACEPOINT,
+	},
+	{
+		"map helper access to adjusted map (via variable): wrong max check",
+		.insns = {
+			BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
+			BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8),
+			BPF_ST_MEM(BPF_DW, BPF_REG_2, 0, 0),
+			BPF_LD_MAP_FD(BPF_REG_1, 0),
+			BPF_EMIT_CALL(BPF_FUNC_map_lookup_elem),
+			BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 7),
+			BPF_MOV64_REG(BPF_REG_2, BPF_REG_0),
+			BPF_LDX_MEM(BPF_W, BPF_REG_3, BPF_REG_0, 0),
+			BPF_JMP_IMM(BPF_JGT, BPF_REG_3,
+				    offsetof(struct other_val, bar) + 1, 4),
+			BPF_ALU64_REG(BPF_ADD, BPF_REG_2, BPF_REG_3),
+			BPF_LD_MAP_FD(BPF_REG_1, 0),
+			BPF_EMIT_CALL(BPF_FUNC_map_lookup_elem),
+			BPF_EXIT_INSN(),
+		},
+		.fixup_map3 = { 3, 11 },
+		.result = REJECT,
+		.errstr = "invalid access to map value, value_size=16 off=9 size=8",
+		.prog_type = BPF_PROG_TYPE_TRACEPOINT,
+	},
+	{
 		"map element value is preserved across register spilling",
 		.insns = {
 			BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
@@ -11533,6 +11790,7 @@ static void do_test_fixup(struct bpf_test *test, struct bpf_insn *prog,
 {
 	int *fixup_map1 = test->fixup_map1;
 	int *fixup_map2 = test->fixup_map2;
+	int *fixup_map3 = test->fixup_map3;
 	int *fixup_prog = test->fixup_prog;
 	int *fixup_map_in_map = test->fixup_map_in_map;
 
@@ -11556,6 +11814,14 @@ static void do_test_fixup(struct bpf_test *test, struct bpf_insn *prog,
 		} while (*fixup_map2);
 	}
 
+	if (*fixup_map3) {
+		map_fds[1] = create_map(sizeof(struct other_val), 1);
+		do {
+			prog[*fixup_map3].imm = map_fds[1];
+			fixup_map3++;
+		} while (*fixup_map3);
+	}
+
 	if (*fixup_prog) {
 		map_fds[2] = create_prog_array();
 		do {