exit: reparent: fix the dead-parent PR_SET_CHILD_SUBREAPER reparenting

The ->has_child_subreaper code in find_new_reaper() finds alive "thread"
but returns another "reaper" thread which can be dead.

Signed-off-by: Oleg Nesterov <[email protected]>
Cc: Aaron Tomlin <[email protected]>
Cc: "Eric W. Biederman" <[email protected]>
Cc: Kay Sievers <[email protected]>
Cc: Lennart Poettering <[email protected]>
Cc: Sterling Alexander <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

diff --git a/kernel/exit.c b/kernel/exit.c
index 9a65f10dc9ff582e9e2232008efbd69427cdabef..fd38a8f0436729eeb7f84108f2e78dfbabaeabb3 100644 (file)
--- a/kernel/exit.c
+++ b/kernel/exit.c
@@ -512,7 +512,7 @@ static struct task_struct *find_new_reaper(struct task_struct *father)
                        thread = reaper;
                        do {
                                if (!(thread->flags & PF_EXITING))
-                                       return reaper;
+                                       return thread;
                        } while_each_thread(reaper, thread);
                }
        }