exit: Fix the exit_code for wait_task_zombie

The function wait_task_zombie is defined to always returns the process not
thread exit status.  Unfortunately when process group exit support
was added to wait_task_zombie the WNOWAIT case was overlooked.

Usually tsk->exit_code and tsk->signal->group_exit_code will be in sync
so fixing this is bug probably has no effect in practice.  But fix
it anyway so that people aren't scratching their heads about why
the two code paths are different.

History-Tree: https://git.kernel.org/pub/scm/linux/kernel/git/tglx/history.git
Fixes: 2c66151cbc2c ("[PATCH] sys_exit() threading improvements, BK-curr")
Link: https://lkml.kernel.org/r/20220103213312.9144-3-ebiederm@xmission.com
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>

diff --git a/kernel/exit.c b/kernel/exit.c
index db86307077d4e5503985c29a4b4e7ed61ba9aac4..b00a25bb4ab939fb54e29785f9365c01c1447080 100644 (file)
--- a/kernel/exit.c
+++ b/kernel/exit.c
@@ -1018,7 +1018,8 @@ static int wait_task_zombie(struct wait_opts *wo, struct task_struct *p)
                return 0;
 
        if (unlikely(wo->wo_flags & WNOWAIT)) {
-               status = p->exit_code;
+               status = (p->signal->flags & SIGNAL_GROUP_EXIT)
+                       ? p->signal->group_exit_code : p->exit_code;
                get_task_struct(p);
                read_unlock(&tasklist_lock);
                sched_annotate_sleep();