When there is tailcall in main prog but there is no tailcall in its subprogs, prog->aux->tail_call_reachable is incorrect for this case. In order to correct it, it has to check subprog[0].has_tail_call at the time when to check subprog[0].tail_call_reachable in check_max_stack_depth_subprog(). It's for fixing a tailcall issue whose patch relies on prog->aux->tail_call_reachable. Signed-off-by: Leon Hwang <hffilwlqm@xxxxxxxxx> --- kernel/bpf/verifier.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c index 9e3aba08984e8..f874ee4b24486 100644 --- a/kernel/bpf/verifier.c +++ b/kernel/bpf/verifier.c @@ -6000,7 +6000,7 @@ static int check_max_stack_depth_subprog(struct bpf_verifier_env *env, int idx) } subprog[ret_prog[j]].tail_call_reachable = true; } - if (subprog[0].tail_call_reachable) + if (subprog[0].tail_call_reachable || subprog[0].has_tail_call) env->prog->aux->tail_call_reachable = true; /* end of for() loop means the last insn of the 'subprog' -- 2.44.0
