From: Sébastien Dugué <sebastien.dugue@bull.net>

  Could you replace make-good_sigevent-non-static.patch with this
patch, as it fixes some problems reported by Oleg Nesterov.

  Oleg, chime in if you still see something I missed.

  Hopefully I will have gotten it right this time.

  Sorry for the hassle.

  Sébastien.


                Make good_sigevent() non-static and rename it

  Move good_sigevent() from posix-timers.c to signal.c where it belongs,
clean it up, rename it to sigevent_find_task() to better describe what the
function does and make it non-static so that it can be used by other
 subsystems.

Signed-off-by: Sébastien Dugué <sebastien.dugue@bull.net>
Cc: Bharata B Rao <bharata@in.ibm.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Suparna Bhattacharya <suparna@in.ibm.com>
Cc: Zach Brown <zach.brown@oracle.com>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Cc: Badari Pulavarty <pbadari@us.ibm.com>
Cc: Benjamin LaHaise <bcrl@linux.intel.com>
Cc: Jean Pierre Dion <jean-pierre.dion@bull.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 kernel/signal.c |   16 ++++++++++------
 1 files changed, 10 insertions(+), 6 deletions(-)

diff -puN kernel/signal.c~make-good_sigevent-non-static-fix kernel/signal.c
--- a/kernel/signal.c~make-good_sigevent-non-static-fix
+++ a/kernel/signal.c
@@ -1097,18 +1097,22 @@ int group_send_sig_info(int sig, struct 
  */
 struct task_struct * sigevent_find_task(sigevent_t * event)
 {
-	struct task_struct *task = NULL;
+	struct task_struct *task = current->group_leader;
 
-	if (event->sigev_signo <= 0 || event->sigev_signo > SIGRTMAX)
-		return NULL;
+	if ((event->sigev_notify & ~SIGEV_THREAD_ID) != SIGEV_NONE) {
+		if (event->sigev_signo <= 0 || event->sigev_signo > SIGRTMAX)
+			return NULL;
+	}
+
+	if (event->sigev_notify & SIGEV_THREAD_ID) {
+		if ((event->sigev_notify & ~SIGEV_THREAD_ID) != SIGEV_SIGNAL)
+			return NULL;
 
-	if ((event->sigev_notify & SIGEV_THREAD_ID ) == SIGEV_THREAD_ID) {
 		task = find_task_by_pid(event->sigev_notify_thread_id);
 
 		if (!task || task->tgid != current->tgid)
 			task = NULL;
-	} else if (event->sigev_notify == SIGEV_SIGNAL)
-		task = current->group_leader;
+	}
 
 	return task;
 }
_