diff options
Diffstat (limited to 'kernel/bpf/verifier.c')
| -rw-r--r-- | kernel/bpf/verifier.c | 18 |
1 files changed, 15 insertions, 3 deletions
diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c index 955c3125576a..813f6ee80419 100644 --- a/kernel/bpf/verifier.c +++ b/kernel/bpf/verifier.c @@ -3551,10 +3551,14 @@ static int map_kptr_match_type(struct bpf_verifier_env *env, * // to match type * * In the kptr_ref case, check_func_arg_reg_off already ensures reg->off - * is zero. + * is zero. We must also ensure that btf_struct_ids_match does not walk + * the struct to match type against first member of struct, i.e. reject + * second case from above. Hence, when type is BPF_KPTR_REF, we set + * strict mode to true for type match. */ if (!btf_struct_ids_match(&env->log, reg->btf, reg->btf_id, reg->off, - off_desc->kptr.btf, off_desc->kptr.btf_id)) + off_desc->kptr.btf, off_desc->kptr.btf_id, + off_desc->type == BPF_KPTR_REF)) goto bad_type; return 0; bad_type: @@ -5593,6 +5597,13 @@ static int check_reg_type(struct bpf_verifier_env *env, u32 regno, found: if (reg->type == PTR_TO_BTF_ID) { + /* For bpf_sk_release, it needs to match against first member + * 'struct sock_common', hence make an exception for it. This + * allows bpf_sk_release to work for multiple socket types. + */ + bool strict_type_match = arg_type_is_release(arg_type) && + meta->func_id != BPF_FUNC_sk_release; + if (!arg_btf_id) { if (!compatible->btf_id) { verbose(env, "verifier internal error: missing arg compatible BTF ID\n"); @@ -5605,7 +5616,8 @@ found: if (map_kptr_match_type(env, meta->kptr_off_desc, reg, regno)) return -EACCES; } else if (!btf_struct_ids_match(&env->log, reg->btf, reg->btf_id, reg->off, - btf_vmlinux, *arg_btf_id)) { + btf_vmlinux, *arg_btf_id, + strict_type_match)) { verbose(env, "R%d is of type %s but %s is expected\n", regno, kernel_type_name(reg->btf, reg->btf_id), kernel_type_name(btf_vmlinux, *arg_btf_id)); |