From: David Emett <dave@sp4m.net>
Date: Sun, 10 Mar 2019 21:43:47 +0000 (+0000)
Subject: tty: fix read of tty->pgrp outside of ctrl_lock
X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=cf90c06f8115016fa4a94644a26a4ba093f0055e;p=linux.git

tty: fix read of tty->pgrp outside of ctrl_lock

The intention was clearly to use the tty_pgrp local variable rather than
re-read tty->pgrp outside of ctrl_lock, so do that.

This bug was introduced by commit 2812d9e9fd94 ("tty: Combine
SIGTTOU/SIGTTIN handling").

Signed-off-by: David Emett <dave@sp4m.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---

diff --git a/drivers/tty/tty_jobctrl.c b/drivers/tty/tty_jobctrl.c
index 1393f71bb1709..f8ed50a168481 100644
--- a/drivers/tty/tty_jobctrl.c
+++ b/drivers/tty/tty_jobctrl.c
@@ -44,7 +44,7 @@ int __tty_check_change(struct tty_struct *tty, int sig)
 	tty_pgrp = tty->pgrp;
 	spin_unlock_irqrestore(&tty->ctrl_lock, flags);
 
-	if (tty_pgrp && pgrp != tty->pgrp) {
+	if (tty_pgrp && pgrp != tty_pgrp) {
 		if (is_ignored(sig)) {
 			if (sig == SIGTTIN)
 				ret = -EIO;