bpf: Add further test_verifier cases for record_func_key

Expand dummy prog generation such that we can easily check on return
codes and add few more test cases to make sure we keep on tracking
pruning behavior.

  # ./test_verifier
  [...]
  #1066/p XDP pkt read, pkt_data <= pkt_meta', bad access 1 OK
  #1067/p XDP pkt read, pkt_data <= pkt_meta', bad access 2 OK
  Summary: 1580 PASSED, 0 SKIPPED, 0 FAILED

Also verified that JIT dump of added test cases looks good.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/df7200b6021444fd369376d227de917357285b65.1576789878.git.daniel@iogearbox.net

2 files changed, 154 insertions, 3 deletions

diff --git a/tools/testing/selftests/bpf/verifier/ref_tracking.c b/tools/testing/selftests/bpf/verifier/ref_tracking.c
index ebcbf154c460..604b46151736 100644
--- a/tools/testing/selftests/bpf/verifier/ref_tracking.c
+++ b/tools/testing/selftests/bpf/verifier/ref_tracking.c
@@ -455,7 +455,7 @@
 	BPF_MOV64_REG(BPF_REG_1, BPF_REG_0),
 	BPF_JMP_IMM(BPF_JNE, BPF_REG_1, 0, 7),
 	/* bpf_tail_call() */
-	BPF_MOV64_IMM(BPF_REG_3, 2),
+	BPF_MOV64_IMM(BPF_REG_3, 3),
 	BPF_LD_MAP_FD(BPF_REG_2, 0),
 	BPF_MOV64_REG(BPF_REG_1, BPF_REG_7),
 	BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_tail_call),
@@ -478,7 +478,7 @@
 	BPF_JMP_IMM(BPF_JEQ, BPF_REG_1, 0, 1),
 	BPF_EMIT_CALL(BPF_FUNC_sk_release),
 	/* bpf_tail_call() */
-	BPF_MOV64_IMM(BPF_REG_3, 2),
+	BPF_MOV64_IMM(BPF_REG_3, 3),
 	BPF_LD_MAP_FD(BPF_REG_2, 0),
 	BPF_MOV64_REG(BPF_REG_1, BPF_REG_7),
 	BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_tail_call),
@@ -497,7 +497,7 @@
 	BPF_SK_LOOKUP(sk_lookup_tcp),
 	/* bpf_tail_call() */
 	BPF_MOV64_REG(BPF_REG_6, BPF_REG_0),
-	BPF_MOV64_IMM(BPF_REG_3, 2),
+	BPF_MOV64_IMM(BPF_REG_3, 3),
 	BPF_LD_MAP_FD(BPF_REG_2, 0),
 	BPF_MOV64_REG(BPF_REG_1, BPF_REG_7),
 	BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_tail_call),
diff --git a/tools/testing/selftests/bpf/verifier/runtime_jit.c b/tools/testing/selftests/bpf/verifier/runtime_jit.c
index a9a8f620e71c..94c399d1faca 100644
--- a/tools/testing/selftests/bpf/verifier/runtime_jit.c
+++ b/tools/testing/selftests/bpf/verifier/runtime_jit.c
@@ -27,6 +27,19 @@
 {
 	"runtime/jit: tail_call within bounds, no prog",
 	.insns = {
+	BPF_MOV64_IMM(BPF_REG_3, 3),
+	BPF_LD_MAP_FD(BPF_REG_2, 0),
+	BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_tail_call),
+	BPF_MOV64_IMM(BPF_REG_0, 1),
+	BPF_EXIT_INSN(),
+	},
+	.fixup_prog1 = { 1 },
+	.result = ACCEPT,
+	.retval = 1,
+},
+{
+	"runtime/jit: tail_call within bounds, key 2",
+	.insns = {
 	BPF_MOV64_IMM(BPF_REG_3, 2),
 	BPF_LD_MAP_FD(BPF_REG_2, 0),
 	BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_tail_call),
@@ -35,9 +48,147 @@
 	},
 	.fixup_prog1 = { 1 },
 	.result = ACCEPT,
+	.retval = 24,
+},
+{
+	"runtime/jit: tail_call within bounds, key 2 / key 2, first branch",
+	.insns = {
+	BPF_MOV64_IMM(BPF_REG_0, 13),
+	BPF_STX_MEM(BPF_B, BPF_REG_1, BPF_REG_0,
+		    offsetof(struct __sk_buff, cb[0])),
+	BPF_LDX_MEM(BPF_B, BPF_REG_0, BPF_REG_1,
+		    offsetof(struct __sk_buff, cb[0])),
+	BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 13, 4),
+	BPF_MOV64_IMM(BPF_REG_3, 2),
+	BPF_LD_MAP_FD(BPF_REG_2, 0),
+	BPF_JMP_IMM(BPF_JA, 0, 0, 3),
+	BPF_MOV64_IMM(BPF_REG_3, 2),
+	BPF_LD_MAP_FD(BPF_REG_2, 0),
+	BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_tail_call),
+	BPF_MOV64_IMM(BPF_REG_0, 1),
+	BPF_EXIT_INSN(),
+	},
+	.fixup_prog1 = { 5, 9 },
+	.result = ACCEPT,
+	.retval = 24,
+},
+{
+	"runtime/jit: tail_call within bounds, key 2 / key 2, second branch",
+	.insns = {
+	BPF_MOV64_IMM(BPF_REG_0, 14),
+	BPF_STX_MEM(BPF_B, BPF_REG_1, BPF_REG_0,
+		    offsetof(struct __sk_buff, cb[0])),
+	BPF_LDX_MEM(BPF_B, BPF_REG_0, BPF_REG_1,
+		    offsetof(struct __sk_buff, cb[0])),
+	BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 13, 4),
+	BPF_MOV64_IMM(BPF_REG_3, 2),
+	BPF_LD_MAP_FD(BPF_REG_2, 0),
+	BPF_JMP_IMM(BPF_JA, 0, 0, 3),
+	BPF_MOV64_IMM(BPF_REG_3, 2),
+	BPF_LD_MAP_FD(BPF_REG_2, 0),
+	BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_tail_call),
+	BPF_MOV64_IMM(BPF_REG_0, 1),
+	BPF_EXIT_INSN(),
+	},
+	.fixup_prog1 = { 5, 9 },
+	.result = ACCEPT,
+	.retval = 24,
+},
+{
+	"runtime/jit: tail_call within bounds, key 0 / key 2, first branch",
+	.insns = {
+	BPF_MOV64_IMM(BPF_REG_0, 13),
+	BPF_STX_MEM(BPF_B, BPF_REG_1, BPF_REG_0,
+		    offsetof(struct __sk_buff, cb[0])),
+	BPF_LDX_MEM(BPF_B, BPF_REG_0, BPF_REG_1,
+		    offsetof(struct __sk_buff, cb[0])),
+	BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 13, 4),
+	BPF_MOV64_IMM(BPF_REG_3, 0),
+	BPF_LD_MAP_FD(BPF_REG_2, 0),
+	BPF_JMP_IMM(BPF_JA, 0, 0, 3),
+	BPF_MOV64_IMM(BPF_REG_3, 2),
+	BPF_LD_MAP_FD(BPF_REG_2, 0),
+	BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_tail_call),
+	BPF_MOV64_IMM(BPF_REG_0, 1),
+	BPF_EXIT_INSN(),
+	},
+	.fixup_prog1 = { 5, 9 },
+	.result = ACCEPT,
+	.retval = 24,
+},
+{
+	"runtime/jit: tail_call within bounds, key 0 / key 2, second branch",
+	.insns = {
+	BPF_MOV64_IMM(BPF_REG_0, 14),
+	BPF_STX_MEM(BPF_B, BPF_REG_1, BPF_REG_0,
+		    offsetof(struct __sk_buff, cb[0])),
+	BPF_LDX_MEM(BPF_B, BPF_REG_0, BPF_REG_1,
+		    offsetof(struct __sk_buff, cb[0])),
+	BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 13, 4),
+	BPF_MOV64_IMM(BPF_REG_3, 0),
+	BPF_LD_MAP_FD(BPF_REG_2, 0),
+	BPF_JMP_IMM(BPF_JA, 0, 0, 3),
+	BPF_MOV64_IMM(BPF_REG_3, 2),
+	BPF_LD_MAP_FD(BPF_REG_2, 0),
+	BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_tail_call),
+	BPF_MOV64_IMM(BPF_REG_0, 1),
+	BPF_EXIT_INSN(),
+	},
+	.fixup_prog1 = { 5, 9 },
+	.result = ACCEPT,
+	.retval = 42,
+},
+{
+	"runtime/jit: tail_call within bounds, different maps, first branch",
+	.insns = {
+	BPF_MOV64_IMM(BPF_REG_0, 13),
+	BPF_STX_MEM(BPF_B, BPF_REG_1, BPF_REG_0,
+		    offsetof(struct __sk_buff, cb[0])),
+	BPF_LDX_MEM(BPF_B, BPF_REG_0, BPF_REG_1,
+		    offsetof(struct __sk_buff, cb[0])),
+	BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 13, 4),
+	BPF_MOV64_IMM(BPF_REG_3, 0),
+	BPF_LD_MAP_FD(BPF_REG_2, 0),
+	BPF_JMP_IMM(BPF_JA, 0, 0, 3),
+	BPF_MOV64_IMM(BPF_REG_3, 0),
+	BPF_LD_MAP_FD(BPF_REG_2, 0),
+	BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_tail_call),
+	BPF_MOV64_IMM(BPF_REG_0, 1),
+	BPF_EXIT_INSN(),
+	},
+	.fixup_prog1 = { 5 },
+	.fixup_prog2 = { 9 },
+	.result_unpriv = REJECT,
+	.errstr_unpriv = "tail_call abusing map_ptr",
+	.result = ACCEPT,
 	.retval = 1,
 },
 {
+	"runtime/jit: tail_call within bounds, different maps, second branch",
+	.insns = {
+	BPF_MOV64_IMM(BPF_REG_0, 14),
+	BPF_STX_MEM(BPF_B, BPF_REG_1, BPF_REG_0,
+		    offsetof(struct __sk_buff, cb[0])),
+	BPF_LDX_MEM(BPF_B, BPF_REG_0, BPF_REG_1,
+		    offsetof(struct __sk_buff, cb[0])),
+	BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 13, 4),
+	BPF_MOV64_IMM(BPF_REG_3, 0),
+	BPF_LD_MAP_FD(BPF_REG_2, 0),
+	BPF_JMP_IMM(BPF_JA, 0, 0, 3),
+	BPF_MOV64_IMM(BPF_REG_3, 0),
+	BPF_LD_MAP_FD(BPF_REG_2, 0),
+	BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_tail_call),
+	BPF_MOV64_IMM(BPF_REG_0, 1),
+	BPF_EXIT_INSN(),
+	},
+	.fixup_prog1 = { 5 },
+	.fixup_prog2 = { 9 },
+	.result_unpriv = REJECT,
+	.errstr_unpriv = "tail_call abusing map_ptr",
+	.result = ACCEPT,
+	.retval = 42,
+},
+{
 	"runtime/jit: tail_call out of bounds",
 	.insns = {
 	BPF_MOV64_IMM(BPF_REG_3, 256),