From 2ae0b31e0faced43c011ce3221f2535721cb6a66 Mon Sep 17 00:00:00 2001
From: Jiri Slaby <jslaby@suse.cz>
Date: Fri, 22 Nov 2019 11:17:21 +0100
Subject: [PATCH] tty: don't crash in tty_init_dev when missing tty_port
We currently warn the user when tty->port is not set in tty_init_dev
yet. The warning says that the kernel will crash later. And it really
will only few lines below at:
tty->port->itty = tty;
So be nice and avoid the crash -- return an error instead. And update
the warning.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Sudip Mukherjee <sudipm.mukherjee@gmail.com>
Link: https://lore.kernel.org/r/20191122101721.7222-1-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/tty/tty_io.c | 9 ++++++---
1 file changed, 6 insertions(+), 3 deletions(-)
diff --git a/drivers/tty/tty_io.c b/drivers/tty/tty_io.c
index e3076ea01222..f16257fdcd45 100644
--- a/drivers/tty/tty_io.c
+++ b/drivers/tty/tty_io.c
@@ -1344,9 +1344,12 @@ struct tty_struct *tty_init_dev(struct tty_driver *driver, int idx)
if (!tty->port)
tty->port = driver->ports[idx];
- WARN_RATELIMIT(!tty->port,
- "%s: %s driver does not set tty->port. This will crash the kernel later. Fix the driver!\n",
- __func__, tty->driver->name);
+ if (WARN_RATELIMIT(!tty->port,
+ "%s: %s driver does not set tty->port. This would crash the kernel. Fix the driver!\n",
+ __func__, tty->driver->name)) {
+ retval = -EINVAL;
+ goto err_release_lock;
+ }
retval = tty_ldisc_lock(tty, 5 * HZ);
if (retval)
--
2.42.0