[3.16.y-ckt stable] Patch "staging: vt6655: device_rx_srv check sk_buff is NULL" has been added to staging queue

[Luis Henriques]

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

    staging: vt6655: device_rx_srv check sk_buff is NULL

to the linux-3.16.y-queue branch of the 3.16.y-ckt extended stable tree 
which can be found at:

    http://kernel.ubuntu.com/git/ubuntu/linux.git/log/?h=linux-3.16.y-queue

This patch is scheduled to be released in version 3.16.7-ckt15.

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

For more information about the 3.16.y-ckt tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable

Thanks.
-Luis

------

>From aa7827c83edfe09647f59581920efc502da0b485 Mon Sep 17 00:00:00 2001
From: Malcolm Priestley <tvboxspy at gmail.com>
Date: Sun, 31 May 2015 10:35:28 +0100
Subject: staging: vt6655: device_rx_srv check sk_buff is NULL

commit b5eeed8cb6097c8ea660b6598d36fdbb94065a22 upstream.

There is a small chance that pRD->pRDInfo->skb could go NULL
while the interrupt is processing.

Put NULL check on loop to break out.

Signed-off-by: Malcolm Priestley <tvboxspy at gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh at linuxfoundation.org>
[ luis: backported to 3.16: adjusted context ]
Signed-off-by: Luis Henriques <luis.henriques at canonical.com>
---
 drivers/staging/vt6655/device_main.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/drivers/staging/vt6655/device_main.c b/drivers/staging/vt6655/device_main.c
index 5a5fd937a442..e3ae2599a2b7 100644
--- a/drivers/staging/vt6655/device_main.c
+++ b/drivers/staging/vt6655/device_main.c
@@ -1402,6 +1402,10 @@ static int device_rx_srv(PSDevice pDevice, unsigned int uIdx) {
 	     pRD = pRD->next) {
 		if (works++ > 15)
 			break;
+
+		if (!pRD->pRDInfo->skb)
+			break;
+
 		if (device_receive_frame(pDevice, pRD)) {
 			if (!device_alloc_rx_buf(pDevice, pRD)) {
 				DBG_PRT(MSG_LEVEL_ERR, KERN_ERR