[PATCH 4.2.y-ckt 204/268] mac80211: fix mgmt-tx abort cookie and leak

From: Kamal Mostafa
Date: Wed Jan 27 2016 - 15:58:38 EST

4.2.8-ckt3 -stable review patch. If anyone has any objections, please let me know.


From: Johannes Berg <johannes.berg@xxxxxxxxx>

commit e673a65952b4ab045a3e3eb200fdf408004fb4fd upstream.

If a mgmt-tx operation is aborted before it runs, the wrong
cookie is reported back to userspace, and the ack_skb gets
leaked since the frame is freed directly instead of freeing
it using ieee80211_free_txskb(). Fix that.

Fixes: 3b79af973cf4 ("mac80211: stop using pointers as userspace cookies")
Signed-off-by: Johannes Berg <johannes.berg@xxxxxxxxx>
Signed-off-by: Kamal Mostafa <kamal@xxxxxxxxxxxxx>
net/mac80211/offchannel.c | 5 ++---
1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/net/mac80211/offchannel.c b/net/mac80211/offchannel.c
index f2c75cf..0dc4291 100644
--- a/net/mac80211/offchannel.c
+++ b/net/mac80211/offchannel.c
@@ -308,11 +308,10 @@ void ieee80211_roc_notify_destroy(struct ieee80211_roc_work *roc, bool free)

/* was never transmitted */
if (roc->frame) {
- cfg80211_mgmt_tx_status(&roc->sdata->wdev,
- (unsigned long)roc->frame,
+ cfg80211_mgmt_tx_status(&roc->sdata->wdev, roc->mgmt_tx_cookie,
roc->frame->data, roc->frame->len,
false, GFP_KERNEL);
- kfree_skb(roc->frame);
+ ieee80211_free_txskb(&roc->sdata->local->hw, roc->frame);

if (!roc->mgmt_tx_cookie)