mac80211: fix txq queue related crashes
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: ba8c3d6f16a1 ("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>
diff --git a/net/mac80211/iface.c b/net/mac80211/iface.c
index 33ae3c8..0451f12 100644
--- a/net/mac80211/iface.c
+++ b/net/mac80211/iface.c
@@ -977,7 +977,10 @@
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);
}