[PATCH 1/1] tty: disassociate_ctty() sends the extra SIGCONT

[Oleg Nesterov <oleg@redhat.com>]

Starting from v3.10 (probably f91e2590 "tty: Signal foreground
group processes in hangup") disassociate_ctty() sends SIGCONT
if tty && on_exit. This breaks LSB test-suite, in particular
test8 in _exit.c and test40 in sigcon5.c.

Put the "!on_exit" check back to restore the old behaviour.

Cc: stable@vger.kernel.org # v3.10+
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Reported-by: Karel Srot <ksrot@redhat.com>
---
 drivers/tty/tty_io.c |    3 ++-
 1 files changed, 2 insertions(+), 1 deletions(-)

diff --git a/drivers/tty/tty_io.c b/drivers/tty/tty_io.c
index a9355ce..3a1a01a 100644
--- a/drivers/tty/tty_io.c
+++ b/drivers/tty/tty_io.c
@@ -854,7 +854,8 @@ void disassociate_ctty(int on_exit)
 			struct pid *tty_pgrp = tty_get_pgrp(tty);
 			if (tty_pgrp) {
 				kill_pgrp(tty_pgrp, SIGHUP, on_exit);
-				kill_pgrp(tty_pgrp, SIGCONT, on_exit);
+				if (!on_exit)
+					kill_pgrp(tty_pgrp, SIGCONT, on_exit);
 				put_pid(tty_pgrp);
 			}
 		}
-- 
1.5.5.1