reparent_thread: don't call kill_orphaned_pgrp() if task_detached()
If task_detached(p) == T, then either
a) p is not the main thread, we will find the group leader on the
->children list.
or
b) p is the group leader but its ->exit_state = EXIT_DEAD. This
can only happen when the last sub-thread has died, but in that case
that thread has already called kill_orphaned_pgrp() from
exit_notify().
In both cases kill_orphaned_pgrp() looks bogus.
Move the task_detached() check up and simplify the code, this is also
right from the "common sense" pov: we should do nothing with the detached
childs, except move them to the new parent's ->children list.
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Cc: Roland McGrath <roland@redhat.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/kernel/exit.c b/kernel/exit.c
index 576eae2..405e687 100644
--- a/kernel/exit.c
+++ b/kernel/exit.c
@@ -818,6 +818,8 @@
list_move_tail(&p->sibling, &p->real_parent->children);
+ if (task_detached(p))
+ return;
/* If this is a threaded reparent there is no need to
* notify anyone anything has happened.
*/
@@ -825,15 +827,13 @@
return;
/* We don't want people slaying init. */
- if (!task_detached(p))
- p->exit_signal = SIGCHLD;
+ p->exit_signal = SIGCHLD;
/* If we'd notified the old parent about this child's death,
* also notify the new parent.
*/
if (!ptrace_reparented(p) &&
- p->exit_state == EXIT_ZOMBIE &&
- !task_detached(p) && thread_group_empty(p))
+ p->exit_state == EXIT_ZOMBIE && thread_group_empty(p))
do_notify_parent(p, p->exit_signal);
kill_orphaned_pgrp(p, father);