Commit d70ab4ad authored Jan 21, 2016 by Michal Kazior Committed by Greg Kroah-Hartman Apr 20, 2016

mac80211: fix txq queue related crashes



commit 2a58d42c1e018ad514d4e23fd33fb2ded95d3ee6 upstream.

The driver can access the queue simultanously
while mac80211 tears down the interface. Without
spinlock protection this could lead to corrupting
sk_buff_head and subsequently to an invalid
pointer dereference.

Fixes: ba8c3d6f ("mac80211: add an intermediate software queue implementation")
Signed-off-by: Michal Kazior <michal.kazior@tieto.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

parent 542afcb4

net/mac80211/iface.c

+3 −0

Original line number	Diff line number	Diff line
		@@ -977,7 +977,10 @@ static void ieee80211_do_stop(struct ieee80211_sub_if_data *sdata,
		if (sdata->vif.txq) {
		struct txq_info *txqi = to_txq_info(sdata->vif.txq);

		spin_lock_bh(&txqi->queue.lock);
		ieee80211_purge_tx_queue(&local->hw, &txqi->queue);
		spin_unlock_bh(&txqi->queue.lock);

		atomic_set(&sdata->txqs_len[txqi->txq.ac], 0);
		}