From: Thomas Gleixner <tglx@linutronix.de>
Date: Wed, 16 Nov 2022 16:21:13 +0000 (+0106)
Subject: serial: kgdboc: Lock console list in probe function
X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=9e409c4778afbbd44759e56ec4bbed839fd31909;p=linux.git

serial: kgdboc: Lock console list in probe function

Unprotected list walks are not necessarily safe.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: John Ogness <john.ogness@linutronix.de>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Reviewed-by: Sergey Senozhatsky <senozhatsky@chromium.org>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/20221116162152.193147-2-john.ogness@linutronix.de
---

diff --git a/drivers/tty/serial/kgdboc.c b/drivers/tty/serial/kgdboc.c
index 7aa37be3216a5..e76f0186c3355 100644
--- a/drivers/tty/serial/kgdboc.c
+++ b/drivers/tty/serial/kgdboc.c
@@ -193,6 +193,7 @@ static int configure_kgdboc(void)
 	if (!p)
 		goto noconfig;
 
+	console_lock();
 	for_each_console(cons) {
 		int idx;
 		if (cons->device && cons->device(cons, &idx) == p &&
@@ -201,6 +202,7 @@ static int configure_kgdboc(void)
 			break;
 		}
 	}
+	console_unlock();
 
 	kgdb_tty_driver = p;
 	kgdb_tty_line = tty_line;