Commit 296fa7f6 authored by Will Newton's avatar Will Newton Committed by Linus Torvalds
Browse files

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: default avatarWill Newton <will.newton@gmail.com>
Signed-off-by: default avatarAlan Cox <alan@redhat.com>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent b4dcfbee

drivers/char/tty_io.c

+9 −6
Original line number Diff line number Diff line
@@ -1795,13 +1795,16 @@ static int __tty_open(struct inode *inode, struct file *filp) 
	}

#endif

	if (device == MKDEV(TTYAUX_MAJOR, 1)) {

		driver = tty_driver_kref_get(console_device(&index));

		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;

	}