From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from xc.sipsolutions.net ([83.246.72.84]:44880 "EHLO sipsolutions.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755233AbZG0Idb (ORCPT ); Mon, 27 Jul 2009 04:33:31 -0400 Subject: [PATCH] mac80211: verify info->control.vif is not NULL From: Johannes Berg To: John Linville Cc: Pavel Roskin , linux-wireless Content-Type: text/plain Date: Mon, 27 Jul 2009 10:33:31 +0200 Message-Id: <1248683611.19945.32.camel@johannes.local> Mime-Version: 1.0 Sender: linux-wireless-owner@vger.kernel.org List-ID: 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 --- net/mac80211/tx.c | 5 +++++ net/mac80211/util.c | 13 +++++++++++++ 2 files changed, 18 insertions(+) --- wireless-testing.orig/net/mac80211/util.c 2009-07-27 10:24:01.000000000 +0200 +++ wireless-testing/net/mac80211/util.c 2009-07-27 10:25:14.000000000 +0200 @@ -336,6 +336,12 @@ void ieee80211_add_pending_skb(struct ie 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 ie 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); --- wireless-testing.orig/net/mac80211/tx.c 2009-07-27 10:23:12.000000000 +0200 +++ wireless-testing/net/mac80211/tx.c 2009-07-27 10:26:55.000000000 +0200 @@ -1889,6 +1889,11 @@ void ieee80211_tx_pending(unsigned long 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,