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

Alexei Starovoitov says:

====================
pull-request: bpf-next 2021-12-30

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

We've added 72 non-merge commits during the last 20 day(s) which contain
a total of 223 files changed, 3510 insertions(+), 1591 deletions(-).

The main changes are:

1) Automatic setrlimit in libbpf when bpf is memcg's in the kernel, from Andrii.

2) Beautify and de-verbose verifier logs, from Christy.

3) Composable verifier types, from Hao.

4) bpf_strncmp helper, from Hou.

5) bpf.h header dependency cleanup, from Jakub.

6) get_func_[arg|ret|arg_cnt] helpers, from Jiri.

7) Sleepable local storage, from KP.

8) Extend kfunc with PTR_TO_CTX, PTR_TO_MEM argument support, from Kumar.
====================

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

1 files changed, 15 insertions, 5 deletions

diff --git a/tools/lib/bpf/relo_core.c b/tools/lib/bpf/relo_core.c
index 32464f0ab4b1..910865e29edc 100644
--- a/tools/lib/bpf/relo_core.c
+++ b/tools/lib/bpf/relo_core.c
@@ -709,10 +709,14 @@ static int bpf_core_calc_field_relo(const char *prog_name,
 
 static int bpf_core_calc_type_relo(const struct bpf_core_relo *relo,
 				   const struct bpf_core_spec *spec,
-				   __u32 *val)
+				   __u32 *val, bool *validate)
 {
 	__s64 sz;
 
+	/* by default, always check expected value in bpf_insn */
+	if (validate)
+		*validate = true;
+
 	/* type-based relos return zero when target type is not found */
 	if (!spec) {
 		*val = 0;
@@ -722,6 +726,11 @@ static int bpf_core_calc_type_relo(const struct bpf_core_relo *relo,
 	switch (relo->kind) {
 	case BPF_CORE_TYPE_ID_TARGET:
 		*val = spec->root_type_id;
+		/* type ID, embedded in bpf_insn, might change during linking,
+		 * so enforcing it is pointless
+		 */
+		if (validate)
+			*validate = false;
 		break;
 	case BPF_CORE_TYPE_EXISTS:
 		*val = 1;
@@ -861,8 +870,8 @@ static int bpf_core_calc_relo(const char *prog_name,
 			res->fail_memsz_adjust = true;
 		}
 	} else if (core_relo_is_type_based(relo->kind)) {
-		err = bpf_core_calc_type_relo(relo, local_spec, &res->orig_val);
-		err = err ?: bpf_core_calc_type_relo(relo, targ_spec, &res->new_val);
+		err = bpf_core_calc_type_relo(relo, local_spec, &res->orig_val, &res->validate);
+		err = err ?: bpf_core_calc_type_relo(relo, targ_spec, &res->new_val, NULL);
 	} else if (core_relo_is_enumval_based(relo->kind)) {
 		err = bpf_core_calc_enumval_relo(relo, local_spec, &res->orig_val);
 		err = err ?: bpf_core_calc_enumval_relo(relo, targ_spec, &res->new_val);
@@ -1213,7 +1222,9 @@ int bpf_core_apply_relo_insn(const char *prog_name, struct bpf_insn *insn,
 
 	/* TYPE_ID_LOCAL relo is special and doesn't need candidate search */
 	if (relo->kind == BPF_CORE_TYPE_ID_LOCAL) {
-		targ_res.validate = true;
+		/* bpf_insn's imm value could get out of sync during linking */
+		memset(&targ_res, 0, sizeof(targ_res));
+		targ_res.validate = false;
 		targ_res.poison = false;
 		targ_res.orig_val = local_spec->root_type_id;
 		targ_res.new_val = local_spec->root_type_id;
@@ -1227,7 +1238,6 @@ int bpf_core_apply_relo_insn(const char *prog_name, struct bpf_insn *insn,
 		return -EOPNOTSUPP;
 	}
 
-
 	for (i = 0, j = 0; i < cands->len; i++) {
 		err = bpf_core_spec_match(local_spec, cands->cands[i].btf,
 					  cands->cands[i].id, cand_spec);