[PATCH 3.12 040/212] cfg80211: fix scheduled scan pointer access

[Greg Kroah-Hartman]

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

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

From: Johannes Berg <johannes.berg@xxxxxxxxx>

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@xxxxxxxxx>
Signed-off-by: Johannes Berg <johannes.berg@xxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
 net/wireless/scan.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

--- a/net/wireless/scan.c
+++ b/net/wireless/scan.c
@@ -254,10 +254,10 @@ void __cfg80211_sched_scan_results(struc
 	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) {


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