diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c index fcdeb00e21c3..bb086eb0c5b2 100644 --- a/kernel/bpf/verifier.c +++ b/kernel/bpf/verifier.c @@ -22542,10 +22542,11 @@ static int check_struct_ops_btf_id(struct bpf_verifier_env *env) const struct bpf_struct_ops *st_ops; const struct btf_member *member; struct bpf_prog *prog = env->prog; + bool has_refcounted_arg = false; u32 btf_id, member_idx; struct btf *btf; const char *mname; - int err; + int i, err; if (!prog->gpl_compatible) { verbose(env, "struct ops programs must have a GPL compatible license\n"); @@ -22615,6 +22616,23 @@ static int check_struct_ops_btf_id(struct bpf_verifier_env *env) return -EACCES; } + for (i = 0; i < st_ops_desc->arg_info[member_idx].cnt; i++) { + if (st_ops_desc->arg_info[member_idx].info->refcounted) { + has_refcounted_arg = true; + break; + } + } + + /* Tail call is not allowed for programs with refcounted arguments since we + * cannot guarantee that valid refcounted kptrs will be passed to the callee. + */ + for (i = 0; i < env->subprog_cnt; i++) { + if (has_refcounted_arg && env->subprog_info[i].has_tail_call) { + verbose(env, "program with __ref argument cannot tail call\n"); + return -EINVAL; + } + } + prog->aux->attach_func_proto = func_proto; prog->aux->attach_func_name = mname; env->ops = st_ops->verifier_ops;