Return-path: Received: from mail-wi0-f172.google.com ([209.85.212.172]:42864 "EHLO mail-wi0-f172.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751032Ab2KEIZp (ORCPT ); Mon, 5 Nov 2012 03:25:45 -0500 Received: by mail-wi0-f172.google.com with SMTP id hq12so2884341wib.1 for ; Mon, 05 Nov 2012 00:25:43 -0800 (PST) From: Arik Nemtsov To: Cc: Johannes Berg , Arik Nemtsov , stable@kernel.org Subject: [PATCH] mac80211: sync acccess to tx_filtered/ps_tx_buf queues Date: Mon, 5 Nov 2012 10:25:39 +0200 Message-Id: <1352103939-7126-1-git-send-email-arik@wizery.com> (sfid-20121105_092558_881354_A497A926) Sender: linux-wireless-owner@vger.kernel.org List-ID: 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. Cc: stable@kernel.org Signed-off-by: Arik Nemtsov Signed-off-by: Ido Yariv --- net/mac80211/sta_info.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/net/mac80211/sta_info.c b/net/mac80211/sta_info.c index f7bb54f..f14655f 100644 --- a/net/mac80211/sta_info.c +++ b/net/mac80211/sta_info.c @@ -982,6 +982,7 @@ void ieee80211_sta_ps_deliver_wakeup(struct sta_info *sta) 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); @@ -997,12 +998,16 @@ void ieee80211_sta_ps_deliver_wakeup(struct sta_info *sta) 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; } -- 1.7.9.5