[PATCH 3.16.y-ckt 062/165] USB: mxuport: fix null deref when used as a console

[Luis Henriques]

3.16.7-ckt9 -stable review patch.  If anyone has any objections, please let me know.

------------------

From: Johan Hovold <johan at kernel.org>

commit db81de767e375743ebb0ad2bcad3326962c2b67e upstream.

Fix null-pointer dereference at probe when the device is used as a
console, in which case the tty argument to open will be NULL.

Fixes: ee467a1f2066 ("USB: serial: add Moxa UPORT 12XX/14XX/16XX
driver")
Signed-off-by: Johan Hovold <johan at kernel.org>
Acked-by: Greg Kroah-Hartman <greg at kroah.com>
Signed-off-by: Luis Henriques <luis.henriques at canonical.com>
---
 drivers/usb/serial/mxuport.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/usb/serial/mxuport.c b/drivers/usb/serial/mxuport.c
index ab1d690274ae..460a40669967 100644
--- a/drivers/usb/serial/mxuport.c
+++ b/drivers/usb/serial/mxuport.c
@@ -1284,7 +1284,8 @@ static int mxuport_open(struct tty_struct *tty, struct usb_serial_port *port)
 	}
 
 	/* Initial port termios */
-	mxuport_set_termios(tty, port, NULL);
+	if (tty)
+		mxuport_set_termios(tty, port, NULL);
 
 	/*
 	 * TODO: use RQ_VENDOR_GET_MSR, once we know what it