bpf, verifier: Correct tail_call_reachable for bpf prog

It's confusing to inspect 'prog->aux->tail_call_reachable' with drgn[0],
when bpf prog has tail call but 'tail_call_reachable' is false.

This patch corrects 'tail_call_reachable' when bpf prog has tail call.

Signed-off-by: Leon Hwang <hffilwlqm@gmail.com>
Link: https://lore.kernel.org/r/20240610124224.34673-2-hffilwlqm@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
This commit is contained in:
Leon Hwang 2024-06-10 20:42:23 +08:00 committed by Alexei Starovoitov
parent f6afdaf72a
commit 01793ed86b

View File

@ -2982,8 +2982,10 @@ static int check_subprogs(struct bpf_verifier_env *env)
if (code == (BPF_JMP | BPF_CALL) &&
insn[i].src_reg == 0 &&
insn[i].imm == BPF_FUNC_tail_call)
insn[i].imm == BPF_FUNC_tail_call) {
subprog[cur_subprog].has_tail_call = true;
subprog[cur_subprog].tail_call_reachable = true;
}
if (BPF_CLASS(code) == BPF_LD &&
(BPF_MODE(code) == BPF_ABS || BPF_MODE(code) == BPF_IND))
subprog[cur_subprog].has_ld_abs = true;