tracehook: fix SA_NOCLDWAIT

I outwitted myself again in commit 2b2a1ff64afbadac842bbc58c5166962cf4f7664,
and broke the SA_NOCLDWAIT behavior so it leaks zombies.  This fixes it.

Reported-by: Andi Kleen <andi@firstfloor.org>
Signed-off-by: Roland McGrath <roland@redhat.com>

1 files changed, 3 insertions, 2 deletions

diff --git a/kernel/signal.c b/kernel/signal.c
index c539f60c6f41..e661b01d340f 100644
--- a/kernel/signal.c
+++ b/kernel/signal.c
@@ -1338,6 +1338,7 @@ int do_notify_parent(struct task_struct *tsk, int sig)
         struct siginfo info;
         unsigned long flags;
         struct sighand_struct *psig;
+        int ret = sig;
 
         BUG_ON(sig == -1);
 
@@ -1402,7 +1403,7 @@ int do_notify_parent(struct task_struct *tsk, int sig)
                  * is implementation-defined: we do (if you don't want
                  * it, just use SIG_IGN instead).
                  */
-                tsk->exit_signal = -1;
+                ret = tsk->exit_signal = -1;
                 if (psig->action[SIGCHLD-1].sa.sa_handler == SIG_IGN)
                         sig = -1;
         }
@@ -1411,7 +1412,7 @@ int do_notify_parent(struct task_struct *tsk, int sig)
         __wake_up_parent(tsk, tsk->parent);
         spin_unlock_irqrestore(&psig->siglock, flags);
 
-        return sig;
+        return ret;
 }
 
 static void do_notify_parent_cldstop(struct task_struct *tsk, int why)