Return-path: Received: from mail-lb0-f174.google.com ([209.85.217.174]:34808 "EHLO mail-lb0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1759002AbcAUNWA (ORCPT ); Thu, 21 Jan 2016 08:22:00 -0500 Received: by mail-lb0-f174.google.com with SMTP id cl12so23080537lbc.1 for ; Thu, 21 Jan 2016 05:21:59 -0800 (PST) From: Michal Kazior To: linux-wireless@vger.kernel.org Cc: johannes@sipsolutions.net, Michal Kazior Subject: [PATCH 1/2] mac80211: fix txq queue related crashes Date: Thu, 21 Jan 2016 14:23:07 +0100 Message-Id: <1453382588-27105-1-git-send-email-michal.kazior@tieto.com> (sfid-20160121_142203_456286_FD7808D4) Sender: linux-wireless-owner@vger.kernel.org List-ID: 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 --- net/mac80211/iface.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/net/mac80211/iface.c b/net/mac80211/iface.c index 33ae3c81bfc5..0451f120746e 100644 --- a/net/mac80211/iface.c +++ b/net/mac80211/iface.c @@ -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); } -- 2.1.4