From: Oleg Nesterov Date: Mon, 24 Mar 2025 17:19:41 +0000 (+0100) Subject: exit: fix the usage of delay_group_leader->exit_code in do_notify_parent() and pidfs_... X-Git-Tag: v6.15-rc1~53^2~4 X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=9133607de37a4887c6f89ed937176a0a0c1ebb17;p=thirdparty%2Fkernel%2Flinux.git exit: fix the usage of delay_group_leader->exit_code in do_notify_parent() and pidfs_exit() Consider a process with a group leader L and a sub-thread T. L does sys_exit(1), then T does sys_exit_group(2). In this case wait_task_zombie(L) will notice SIGNAL_GROUP_EXIT and use L->signal->group_exit_code, this is correct. But, before that, do_notify_parent(L) called by release_task(T) will use L->exit_code != L->signal->group_exit_code, and this is not consistent. We don't really care, I think that nobody relies on the info which comes with SIGCHLD, if nothing else SIGCHLD < SIGRTMIN can be queued only once. But pidfs_exit() is more problematic, I think pidfs_exit_info->exit_code should report ->group_exit_code in this case, just like wait_task_zombie(). TODO: with this change we can hopefully cleanup (or may be even kill) the similar SIGNAL_GROUP_EXIT checks, at least in wait_task_zombie(). Signed-off-by: Oleg Nesterov Link: https://lore.kernel.org/r/20250324171941.GA13114@redhat.com Signed-off-by: Christian Brauner --- diff --git a/kernel/exit.c b/kernel/exit.c index 5d1226fdfadcc..1b51dc099f1e0 100644 --- a/kernel/exit.c +++ b/kernel/exit.c @@ -268,6 +268,9 @@ repeat: leader = p->group_leader; if (leader != p && thread_group_empty(leader) && leader->exit_state == EXIT_ZOMBIE) { + /* for pidfs_exit() and do_notify_parent() */ + if (leader->signal->flags & SIGNAL_GROUP_EXIT) + leader->exit_code = leader->signal->group_exit_code; /* * If we were the last child thread and the leader has * exited already, and the leader's parent ignores SIGCHLD,