linux-kernel - [ 04/89] mac80211: sync acccess to tx_filtered/ps_tx

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <20121203143147.274474404@decadent.org.uk>
Date:	Mon, 03 Dec 2012 14:31:50 +0000
From:	Ben Hutchings <ben@...adent.org.uk>
To:	linux-kernel@...r.kernel.org, stable@...r.kernel.org
Cc:	akpm@...ux-foundation.org, alan@...rguk.ukuu.org.uk,
	Arik Nemtsov <arik@...ery.com>, Ido Yariv <ido@...ery.com>,
	Johannes Berg <johannes.berg@...el.com>
Subject: [ 04/89] mac80211: sync acccess to tx_filtered/ps_tx_buf queues

3.2-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Arik Nemtsov <arik@...ery.com>

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 <arik@...ery.com>
Signed-off-by: Ido Yariv <ido@...ery.com>
Signed-off-by: Johannes Berg <johannes.berg@...el.com>
Signed-off-by: Ben Hutchings <ben@...adent.org.uk>
---
 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 797dd36..89ccd3e 100644
--- a/net/mac80211/sta_info.c
+++ b/net/mac80211/sta_info.c
@@ -961,6 +961,7 @@ 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);
 
@@ -976,12 +977,16 @@ 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;
 	}


--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/