From: Arik Nemtsov Date: Mon, 5 Nov 2012 08:27:52 +0000 (+0200) Subject: mac80211: sync acccess to tx_filtered/ps_tx_buf queues X-Git-Tag: v3.4.20~168 X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=1cbc74e7edf24ac527c502e3e936bc4350ec4622;p=karo-tx-linux.git mac80211: sync acccess to tx_filtered/ps_tx_buf queues 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 --- diff --git a/net/mac80211/sta_info.c b/net/mac80211/sta_info.c index d93d39b84344..6e36aafbf5e0 100644 --- a/net/mac80211/sta_info.c +++ b/net/mac80211/sta_info.c @@ -959,6 +959,7 @@ 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); @@ -974,12 +975,16 @@ 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; }