Patch "cfg80211: wext: clear sinfo struct before calling driver" has been added to the 3.14-stable tree

This is a note to let you know that I've just added the patch titled

cfg80211: wext: clear sinfo struct before calling driver

to the 3.14-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
cfg80211-wext-clear-sinfo-struct-before-calling-driver.patch
and it can be found in the queue-3.14 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let <[email protected]> know about it.

From: Johannes Berg <[email protected]>
Date: Tue, 9 Jun 2015 21:35:44 +0200
Subject: cfg80211: wext: clear sinfo struct before calling driver

From: Johannes Berg <[email protected]>

commit 9c5a18a31b321f120efda412281bb9f610f84aa0 upstream.

Until recently, mac80211 overwrote all the statistics it could provide when getting called, but it now relies on the struct having been zeroed by the caller. This was always the case in nl80211, but wext used a static struct which could even cause values from one device leak to another.

Using a static struct is OK (as even documented in a comment) since the whole usage of this function and its return value is always locked under RTNL. Not clearing the struct for calling the driver has always been wrong though, since drivers were free to only fill values they could report, so calling this for one device and then for another would always have leaked values from one to the other.

Fix this by initializing the structure in question before the driver method call.

This fixes https://bugzilla.kernel.org/show_bug.cgi?id=99691

---
 net/wireless/wext-compat.c |    2 ++
 1 file changed, 2 insertions(+)

@@ -1331,6 +1331,8 @@ static struct iw_statistics *cfg80211_wi
 	memcpy(bssid, wdev->current_bss->pub.bssid, ETH_ALEN);
 	wdev_unlock(wdev);
 
+	memset(&sinfo, 0, sizeof(sinfo));
+
 	if (rdev_get_station(rdev, dev, bssid, &sinfo))
 		return NULL;
 

Patches currently in stable-queue which might be from [email protected] are

queue-3.14/cfg80211-wext-clear-sinfo-struct-before-calling-driver.patch --
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