From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932864Ab2KVV6Z (ORCPT ); Thu, 22 Nov 2012 16:58:25 -0500 Received: from mail.kernel.org ([198.145.19.201]:49646 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754906Ab2KVSkN (ORCPT ); Thu, 22 Nov 2012 13:40:13 -0500 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Greg Kroah-Hartman , alan@lxorguk.ukuu.org.uk, Arik Nemtsov , Ido Yariv , Johannes Berg Subject: [ 04/83] mac80211: sync acccess to tx_filtered/ps_tx_buf queues Date: Wed, 21 Nov 2012 16:41:26 -0800 Message-Id: <20121122004212.885130637@linuxfoundation.org> X-Mailer: git-send-email 1.8.0.197.g5a90748 In-Reply-To: <20121122004212.371862690@linuxfoundation.org> References: <20121122004212.371862690@linuxfoundation.org> User-Agent: quilt/0.60-2.1.2 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.6-stable review patch. If anyone has any objections, please let me know. ------------------ From: Arik Nemtsov commit 987c285c2ae2e4e32aca3a9b3252d28171c75711 upstream. These are accessed without a lock when ending STA PSM. If the sta_cleanup timer accesses these lists at the same time, we might crash. This may fix some mysterious crashes we had during ieee80211_sta_ps_deliver_wakeup. Signed-off-by: Arik Nemtsov Signed-off-by: Ido Yariv Signed-off-by: Johannes Berg Signed-off-by: Greg Kroah-Hartman --- net/mac80211/sta_info.c | 5 +++++ 1 file changed, 5 insertions(+) --- a/net/mac80211/sta_info.c +++ b/net/mac80211/sta_info.c @@ -948,6 +948,7 @@ void ieee80211_sta_ps_deliver_wakeup(str struct ieee80211_local *local = sdata->local; struct sk_buff_head pending; int filtered = 0, buffered = 0, ac; + unsigned long flags; clear_sta_flag(sta, WLAN_STA_SP); @@ -963,12 +964,16 @@ void ieee80211_sta_ps_deliver_wakeup(str for (ac = 0; ac < IEEE80211_NUM_ACS; ac++) { int count = skb_queue_len(&pending), tmp; + spin_lock_irqsave(&sta->tx_filtered[ac].lock, flags); skb_queue_splice_tail_init(&sta->tx_filtered[ac], &pending); + spin_unlock_irqrestore(&sta->tx_filtered[ac].lock, flags); tmp = skb_queue_len(&pending); filtered += tmp - count; count = tmp; + spin_lock_irqsave(&sta->ps_tx_buf[ac].lock, flags); skb_queue_splice_tail_init(&sta->ps_tx_buf[ac], &pending); + spin_unlock_irqrestore(&sta->ps_tx_buf[ac].lock, flags); tmp = skb_queue_len(&pending); buffered += tmp - count; }