[PATCH printk v2 01/38] serial: kgdboc: Lock console list in probe function

From: John Ogness
Date: Wed Oct 19 2022 - 11:03:05 EST


From: Thomas Gleixner <tglx@xxxxxxxxxxxxx>

Unprotected list walks are not necessarily safe.

Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Signed-off-by: John Ogness <john.ogness@xxxxxxxxxxxxx>
Reviewed-by: Petr Mladek <pmladek@xxxxxxxx>
---
drivers/tty/serial/kgdboc.c | 2 ++
1 file changed, 2 insertions(+)

diff --git a/drivers/tty/serial/kgdboc.c b/drivers/tty/serial/kgdboc.c
index 7aa37be3216a..e76f0186c335 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;
--
2.30.2