Return-path: Received: from mail.toke.dk ([52.28.52.200]:60725 "EHLO mail.toke.dk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728509AbeHMO6s (ORCPT ); Mon, 13 Aug 2018 10:58:48 -0400 From: =?UTF-8?q?Toke=20H=C3=B8iland-J=C3=B8rgensen?= To: linux-wireless@vger.kernel.org Cc: Ben Greear , =?UTF-8?q?Toke=20H=C3=B8iland-J=C3=B8rgensen?= Subject: [PATCH] mac80211: Run TXQ teardown code before de-registering interfaces Date: Mon, 13 Aug 2018 14:16:25 +0200 Message-Id: <20180813121625.18367-1-toke@toke.dk> (sfid-20180813_141753_865995_53B23CAB) MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-wireless-owner@vger.kernel.org List-ID: The TXQ teardown code can reference the vif data structures that are stored in the netdev private memory area if there are still packets on the queue when it is being freed. Since the TXQ teardown code is run after the netdevs are freed, this can lead to a use-after-free. Fix this by moving the TXQ teardown code to earlier in ieee80211_unregister_hw(). Reported-by: Ben Greear Tested-by: Ben Greear Signed-off-by: Toke Høiland-Jørgensen --- net/mac80211/main.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/net/mac80211/main.c b/net/mac80211/main.c index e054a2fd8d38..98a5c15e8db1 100644 --- a/net/mac80211/main.c +++ b/net/mac80211/main.c @@ -1170,6 +1170,7 @@ void ieee80211_unregister_hw(struct ieee80211_hw *hw) #if IS_ENABLED(CONFIG_IPV6) unregister_inet6addr_notifier(&local->ifa6_notifier); #endif + ieee80211_txq_teardown_flows(local); rtnl_lock(); @@ -1198,7 +1199,6 @@ void ieee80211_unregister_hw(struct ieee80211_hw *hw) skb_queue_purge(&local->skb_queue); skb_queue_purge(&local->skb_queue_unreliable); skb_queue_purge(&local->skb_queue_tdls_chsw); - ieee80211_txq_teardown_flows(local); destroy_workqueue(local->workqueue); wiphy_unregister(local->hw.wiphy); -- 2.18.0