lkml.org 
[lkml]   [2012]   [Dec]   [3]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
Date
From
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@wizery.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@wizery.com>
Signed-off-by: Ido Yariv <ido@wizery.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Ben Hutchings <ben@decadent.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;
}



\
 
 \ /
  Last update: 2012-12-03 18:01    [W:0.380 / U:0.532 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site