[3.11.y.z extended stable] Patch "cfg80211: fix scheduled scan pointer access" has been added to staging queue

[Luis Henriques]

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

    cfg80211: fix scheduled scan pointer access

to the linux-3.11.y-queue branch of the 3.11.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-3.11.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 3.11.y.z tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable

Thanks.
-Luis

------

>From b7eda9e8a694014fc6d98f9f097439ca4363056c Mon Sep 17 00:00:00 2001
From: Johannes Berg <johannes.berg at intel.com>
Date: Mon, 21 Oct 2013 11:33:35 +0200
Subject: cfg80211: fix scheduled scan pointer access

commit 79845c662eeb95c9a180b9bd0d3ad848ee65b94c upstream.

Since rdev->sched_scan_req is dereferenced outside the
lock protecting it, this might be done at the wrong
time, causing crashes. Move the dereference to where
it should be - inside the RTNL locked section.

Reviewed-by: Emmanuel Grumbach <emmanuel.grumbach at intel.com>
Signed-off-by: Johannes Berg <johannes.berg at intel.com>
Signed-off-by: Luis Henriques <luis.henriques at canonical.com>
---
 net/wireless/scan.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/net/wireless/scan.c b/net/wireless/scan.c
index ae8c186..7811f81 100644
--- a/net/wireless/scan.c
+++ b/net/wireless/scan.c
@@ -254,10 +254,10 @@ void __cfg80211_sched_scan_results(struct work_struct *wk)
 	rdev = container_of(wk, struct cfg80211_registered_device,
 			    sched_scan_results_wk);

-	request = rdev->sched_scan_req;
-
 	rtnl_lock();

+	request = rdev->sched_scan_req;
+
 	/* we don't have sched_scan_req anymore if the scan is stopping */
 	if (request) {
 		if (request->flags & NL80211_SCAN_FLAG_FLUSH) {
--
1.8.3.2