From 296fa7f6a3f3342d40df7713e74246198295654b Mon Sep 17 00:00:00 2001 From: Will Newton Date: Mon, 1 Dec 2008 11:36:06 +0000 Subject: [PATCH] drivers/char/tty_io.c: Avoid panic when no console is configured. When no console is configured tty_open tries to call kref_get on a NULL pointer, return ENODEV instead. Signed-off-by: Will Newton Signed-off-by: Alan Cox Signed-off-by: Linus Torvalds --- drivers/char/tty_io.c | 15 +++++++++------ 1 file changed, 9 insertions(+), 6 deletions(-) diff --git a/drivers/char/tty_io.c b/drivers/char/tty_io.c index 59f472143f0..1412a8d1e58 100644 --- a/drivers/char/tty_io.c +++ b/drivers/char/tty_io.c @@ -1795,12 +1795,15 @@ retry_open: } #endif if (device == MKDEV(TTYAUX_MAJOR, 1)) { - driver = tty_driver_kref_get(console_device(&index)); - if (driver) { - /* Don't let /dev/console block */ - filp->f_flags |= O_NONBLOCK; - noctty = 1; - goto got_driver; + struct tty_driver *console_driver = console_device(&index); + if (console_driver) { + driver = tty_driver_kref_get(console_driver); + if (driver) { + /* Don't let /dev/console block */ + filp->f_flags |= O_NONBLOCK; + noctty = 1; + goto got_driver; + } } mutex_unlock(&tty_mutex); return -ENODEV; -- 2.20.1