From: Oleg Nesterov <oleg@redhat.com>
Date: Fri, 2 Apr 2010 16:05:12 +0000 (+0200)
Subject: tty: release_one_tty() forgets to put pids
X-Git-Tag: firefly_0821_release~10186^2~1875
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=e2278e63b10b17980dcbc01e24fe0619f4b38bfd;p=firefly-linux-kernel-4.4.55.git

tty: release_one_tty() forgets to put pids

commit 6da8d866d0d39e9509ff826660f6a86a6757c966 upstream.

release_one_tty(tty) can be called when tty still has a reference
to pgrp/session. In this case we leak the pid.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Reported-by: Catalin Marinas <catalin.marinas@arm.com>
Reported-and-tested-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Acked-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
---

diff --git a/drivers/char/tty_io.c b/drivers/char/tty_io.c
index 05cab2cea85e..53ffcfc1154b 100644
--- a/drivers/char/tty_io.c
+++ b/drivers/char/tty_io.c
@@ -1408,6 +1408,8 @@ static void release_one_tty(struct work_struct *work)
 	list_del_init(&tty->tty_files);
 	file_list_unlock();
 
+	put_pid(tty->pgrp);
+	put_pid(tty->session);
 	free_tty_struct(tty);
 }