signal: sys_pause() should check signal_pending()

ERESTART* is always wrong without TIF_SIGPENDING. Teach sys_pause()
to handle the spurious wakeup correctly.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>

diff --git a/kernel/signal.c b/kernel/signal.c
index ad5e818..86c32b8 100644 (file)
--- a/kernel/signal.c
+++ b/kernel/signal.c
@@ -3023,8 +3023,10 @@ SYSCALL_DEFINE2(signal, int, sig, __sighandler_t, handler)
 
 SYSCALL_DEFINE0(pause)
 {
-       current->state = TASK_INTERRUPTIBLE;
-       schedule();
+       while (!signal_pending(current)) {
+               current->state = TASK_INTERRUPTIBLE;
+               schedule();
+       }
        return -ERESTARTNOHAND;
 }