From a7bc376c858e0e724b8cb2db09b6874562d377ca Mon Sep 17 00:00:00 2001 From: Johannes Berg Date: Mon, 27 Jul 2009 10:33:31 +0200 Subject: [PATCH] mac80211: verify info->control.vif is not NULL When enqueuing packets on the internal packet queue, we need to ensure that we have a valid vif pointer since that is required since the net namespace work. Add some assertions to verify this, but also don't crash is for some reason we don't end up with a vif pointer -- warn and drop the packet in all these cases. Since this code touches a number of hotpaths, it is intended to be temporary, or maybe configurable in the future, at least the bit that is in the path that gets hit for every packet, ieee80211_tx_pending(). Signed-off-by: Johannes Berg Signed-off-by: John W. Linville --- net/mac80211/tx.c | 5 +++++ net/mac80211/util.c | 13 +++++++++++++ 2 files changed, 18 insertions(+) diff --git a/net/mac80211/tx.c b/net/mac80211/tx.c index 9e5dff1c8f27..4e1b2ba122cd 100644 --- a/net/mac80211/tx.c +++ b/net/mac80211/tx.c @@ -1889,6 +1889,11 @@ void ieee80211_tx_pending(unsigned long data) struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); struct ieee80211_sub_if_data *sdata; + if (WARN_ON(!info->control.vif)) { + kfree_skb(skb); + continue; + } + sdata = vif_to_sdata(info->control.vif); dev_hold(sdata->dev); spin_unlock_irqrestore(&local->queue_stop_reason_lock, diff --git a/net/mac80211/util.c b/net/mac80211/util.c index 7fc55846d601..8502936e5314 100644 --- a/net/mac80211/util.c +++ b/net/mac80211/util.c @@ -336,6 +336,12 @@ void ieee80211_add_pending_skb(struct ieee80211_local *local, struct ieee80211_hw *hw = &local->hw; unsigned long flags; int queue = skb_get_queue_mapping(skb); + struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); + + if (WARN_ON(!info->control.vif)) { + kfree(skb); + return; + } spin_lock_irqsave(&local->queue_stop_reason_lock, flags); __ieee80211_stop_queue(hw, queue, IEEE80211_QUEUE_STOP_REASON_SKB_ADD); @@ -358,6 +364,13 @@ int ieee80211_add_pending_skbs(struct ieee80211_local *local, IEEE80211_QUEUE_STOP_REASON_SKB_ADD); while ((skb = skb_dequeue(skbs))) { + struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); + + if (WARN_ON(!info->control.vif)) { + kfree(skb); + continue; + } + ret++; queue = skb_get_queue_mapping(skb); __skb_queue_tail(&local->pending[queue], skb); -- 2.39.5