[3.13.y.z extended stable] Patch "mac80211: fix potential use-after-free" has been added to staging queue

[Kamal Mostafa]

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

    mac80211: fix potential use-after-free

to the linux-3.13.y-queue branch of the 3.13.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-3.13.y-queue

This patch is scheduled to be released in version 3.13.11.1.

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

For more information about the 3.13.y.z tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable

Thanks.
-Kamal

------

>From d9b1a8856ff603b45266b4e1c58fbf5b7c74979c Mon Sep 17 00:00:00 2001
From: Johannes Berg <johannes.berg at intel.com>
Date: Tue, 4 Mar 2014 11:43:28 +0100
Subject: mac80211: fix potential use-after-free

commit d2722f8b87fb172ff2f31d3a2816b31d58678d40 upstream.

The bss struct might be freed in ieee80211_rx_bss_put(),
so we shouldn't use it afterwards.

Fixes: 817cee7675237 ("mac80211: track AP's beacon rate and give it to the driver")
Signed-off-by: Johannes Berg <johannes.berg at intel.com>
Signed-off-by: Kamal Mostafa <kamal at canonical.com>
---
 net/mac80211/mlme.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/net/mac80211/mlme.c b/net/mac80211/mlme.c
index 72ad37d..90ee798 100644
--- a/net/mac80211/mlme.c
+++ b/net/mac80211/mlme.c
@@ -2691,8 +2691,8 @@ static void ieee80211_rx_bss_info(struct ieee80211_sub_if_data *sdata,
 	bss = ieee80211_bss_info_update(local, rx_status, mgmt, len, elems,
 					channel);
 	if (bss) {
-		ieee80211_rx_bss_put(local, bss);
 		sdata->vif.bss_conf.beacon_rate = bss->beacon_rate;
+		ieee80211_rx_bss_put(local, bss);
 	}
 }

--
1.9.1