diff options
Diffstat (limited to 'kernel/bpf/verifier.c')
-rw-r--r-- | kernel/bpf/verifier.c | 21 |
1 files changed, 16 insertions, 5 deletions
diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c index df3ec6b05f05..e3cf6194c24f 100644 --- a/kernel/bpf/verifier.c +++ b/kernel/bpf/verifier.c @@ -10444,11 +10444,21 @@ static int check_return_code(struct bpf_verifier_env *env) const bool is_subprog = frame->subprogno; /* LSM and struct_ops func-ptr's return type could be "void" */ - if (!is_subprog && - (prog_type == BPF_PROG_TYPE_STRUCT_OPS || - prog_type == BPF_PROG_TYPE_LSM) && - !prog->aux->attach_func_proto->type) - return 0; + if (!is_subprog) { + switch (prog_type) { + case BPF_PROG_TYPE_LSM: + if (prog->expected_attach_type == BPF_LSM_CGROUP) + /* See below, can be 0 or 0-1 depending on hook. */ + break; + fallthrough; + case BPF_PROG_TYPE_STRUCT_OPS: + if (!prog->aux->attach_func_proto->type) + return 0; + break; + default: + break; + } + } /* eBPF calling convention is such that R0 is used * to return the value from eBPF program. @@ -10572,6 +10582,7 @@ static int check_return_code(struct bpf_verifier_env *env) if (!tnum_in(range, reg->var_off)) { verbose_invalid_scalar(env, reg, &range, "program exit", "R0"); if (prog->expected_attach_type == BPF_LSM_CGROUP && + prog_type == BPF_PROG_TYPE_LSM && !prog->aux->attach_func_proto->type) verbose(env, "Note, BPF_LSM_CGROUP that attach to void LSM hooks can't modify return value!\n"); return -EINVAL; |