[3.5.y.z extended stable] Patch "USB: mos7840: fix tiocmget error handling" has been added to staging queue

[Luis Henriques]

This is a note to let you know that I have just added a patch titled

    USB: mos7840: fix tiocmget error handling

to the linux-3.5.y-queue branch of the 3.5.y.z extended stable tree 
which can be found at:

 http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.5.y-queue

If you, or anyone else, feels it should not be added to this tree, please 
reply to this email.

For more information about the 3.5.y.z tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable

Thanks.
-Luis

------

>From b533e8e94a58fba5cf12bb2d1a4329da778ede01 Mon Sep 17 00:00:00 2001
From: Johan Hovold <jhovold at gmail.com>
Date: Wed, 9 Oct 2013 17:01:09 +0200
Subject: USB: mos7840: fix tiocmget error handling

commit a91ccd26e75235d86248d018fe3779732bcafd8d upstream.

Make sure to return errors from tiocmget rather than rely on
uninitialised stack data.

Signed-off-by: Johan Hovold <jhovold at gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh at linuxfoundation.org>
Signed-off-by: Luis Henriques <luis.henriques at canonical.com>
---
 drivers/usb/serial/mos7840.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/drivers/usb/serial/mos7840.c b/drivers/usb/serial/mos7840.c
index d9368be..08aad01 100644
--- a/drivers/usb/serial/mos7840.c
+++ b/drivers/usb/serial/mos7840.c
@@ -1707,7 +1707,11 @@ static int mos7840_tiocmget(struct tty_struct *tty)
 		return -ENODEV;

 	status = mos7840_get_uart_reg(port, MODEM_STATUS_REGISTER, &msr);
+	if (status != 1)
+		return -EIO;
 	status = mos7840_get_uart_reg(port, MODEM_CONTROL_REGISTER, &mcr);
+	if (status != 1)
+		return -EIO;
 	result = ((mcr & MCR_DTR) ? TIOCM_DTR : 0)
 	    | ((mcr & MCR_RTS) ? TIOCM_RTS : 0)
 	    | ((mcr & MCR_LOOPBACK) ? TIOCM_LOOP : 0)
--
1.8.3.2