From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752704AbcHKKQE (ORCPT ); Thu, 11 Aug 2016 06:16:04 -0400 Received: from mx1.redhat.com ([209.132.183.28]:46664 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752590AbcHKKQC (ORCPT ); Thu, 11 Aug 2016 06:16:02 -0400 From: Jason Wang To: netdev@vger.kernel.org, linux-kernel@vger.kernel.org, davem@davemloft.net Cc: borntraeger@de.ibm.com, cornelia.huck@de.ibm.com, mst@redhat.com, Jason Wang Subject: [PATCH net] macvtap: fix use after free for skb_array during release Date: Thu, 11 Aug 2016 18:15:56 +0800 Message-Id: <1470910556-11872-1-git-send-email-jasowang@redhat.com> X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.30]); Thu, 11 Aug 2016 10:16:01 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org We've clean skb_array in macvtap_put_queue() but still try to pop from it during macvtap_sock_destruct(). Fix this use after free by moving the skb array cleanup to macvtap_sock_destruct() instead. Fixes: 362899b8725b ("macvtap: switch to use skb array") Reported-by: Cornelia Huck Tested-by: Cornelia Huck Signed-off-by: Jason Wang --- drivers/net/macvtap.c | 5 +---- 1 file changed, 1 insertion(+), 4 deletions(-) diff --git a/drivers/net/macvtap.c b/drivers/net/macvtap.c index a38c0da..070e329 100644 --- a/drivers/net/macvtap.c +++ b/drivers/net/macvtap.c @@ -275,7 +275,6 @@ static void macvtap_put_queue(struct macvtap_queue *q) rtnl_unlock(); synchronize_rcu(); - skb_array_cleanup(&q->skb_array); sock_put(&q->sk); } @@ -533,10 +532,8 @@ static void macvtap_sock_write_space(struct sock *sk) static void macvtap_sock_destruct(struct sock *sk) { struct macvtap_queue *q = container_of(sk, struct macvtap_queue, sk); - struct sk_buff *skb; - while ((skb = skb_array_consume(&q->skb_array)) != NULL) - kfree_skb(skb); + skb_array_cleanup(&q->skb_array); } static int macvtap_open(struct inode *inode, struct file *file) -- 2.7.4