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| author | Kumar Kartikeya Dwivedi <memxor@gmail.com> | 2022-03-20 17:30:03 +0300 |
|---|---|---|
| committer | Alexei Starovoitov <ast@kernel.org> | 2022-03-21 05:21:38 +0300 |
| commit | 7ada3787e91c89b0aa7abf47682e8e587b855c13 (patch) | |
| tree | e85380b9690ec176cbff5a327a1156424250ee71 /kernel/bpf | |
| parent | e1cc1f39981b06ba22a0c92e800e9fd8ba59d2d3 (diff) | |
| download | linux-7ada3787e91c89b0aa7abf47682e8e587b855c13.tar.xz | |
bpf: Check for NULL return from bpf_get_btf_vmlinux
When CONFIG_DEBUG_INFO_BTF is disabled, bpf_get_btf_vmlinux can return a
NULL pointer. Check for it in btf_get_module_btf to prevent a NULL pointer
dereference.
While kernel test robot only complained about this specific case, let's
also check for NULL in other call sites of bpf_get_btf_vmlinux.
Fixes: 9492450fd287 ("bpf: Always raise reference in btf_get_module_btf")
Reported-by: kernel test robot <oliver.sang@intel.com>
Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20220320143003.589540-1-memxor@gmail.com
Diffstat (limited to 'kernel/bpf')
| -rw-r--r-- | kernel/bpf/btf.c | 6 |
1 files changed, 5 insertions, 1 deletions
diff --git a/kernel/bpf/btf.c b/kernel/bpf/btf.c index 6d9e711cb5d4..ce212bf39b2b 100644 --- a/kernel/bpf/btf.c +++ b/kernel/bpf/btf.c @@ -534,6 +534,8 @@ static s32 bpf_find_btf_id(const char *name, u32 kind, struct btf **btf_p) btf = bpf_get_btf_vmlinux(); if (IS_ERR(btf)) return PTR_ERR(btf); + if (!btf) + return -EINVAL; ret = btf_find_by_name_kind(btf, name, kind); /* ret is never zero, since btf_find_by_name_kind returns @@ -6584,7 +6586,7 @@ static struct btf *btf_get_module_btf(const struct module *module) if (!module) { btf = bpf_get_btf_vmlinux(); - if (!IS_ERR(btf)) + if (!IS_ERR_OR_NULL(btf)) btf_get(btf); return btf; } @@ -7180,6 +7182,8 @@ bpf_core_find_cands(struct bpf_core_ctx *ctx, u32 local_type_id) main_btf = bpf_get_btf_vmlinux(); if (IS_ERR(main_btf)) return ERR_CAST(main_btf); + if (!main_btf) + return ERR_PTR(-EINVAL); local_type = btf_type_by_id(local_btf, local_type_id); if (!local_type) |