From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753194AbdEAVxg (ORCPT ); Mon, 1 May 2017 17:53:36 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:58034 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752658AbdEAVci (ORCPT ); Mon, 1 May 2017 17:32:38 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Joe Ghalam , Herbert Xu , "David S. Miller" Subject: [PATCH 4.9 31/54] macvlan: Fix device ref leak when purging bc_queue Date: Mon, 1 May 2017 14:31:38 -0700 Message-Id: <20170501212632.997105182@linuxfoundation.org> X-Mailer: git-send-email 2.12.2 In-Reply-To: <20170501212631.798128131@linuxfoundation.org> References: <20170501212631.798128131@linuxfoundation.org> User-Agent: quilt/0.65 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 4.9-stable review patch. If anyone has any objections, please let me know. ------------------ From: Herbert Xu [ Upstream commit f6478218e6edc2a587b8f132f66373baa7b2497c ] When a parent macvlan device is destroyed we end up purging its broadcast queue without dropping the device reference count on the packet source device. This causes the source device to linger. This patch drops that reference count. Fixes: 260916dfb48c ("macvlan: Fix potential use-after free for...") Reported-by: Joe Ghalam Signed-off-by: Herbert Xu Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- drivers/net/macvlan.c | 11 ++++++++++- 1 file changed, 10 insertions(+), 1 deletion(-) --- a/drivers/net/macvlan.c +++ b/drivers/net/macvlan.c @@ -1140,6 +1140,7 @@ static int macvlan_port_create(struct ne static void macvlan_port_destroy(struct net_device *dev) { struct macvlan_port *port = macvlan_port_get_rtnl(dev); + struct sk_buff *skb; dev->priv_flags &= ~IFF_MACVLAN_PORT; netdev_rx_handler_unregister(dev); @@ -1148,7 +1149,15 @@ static void macvlan_port_destroy(struct * but we need to cancel it and purge left skbs if any. */ cancel_work_sync(&port->bc_work); - __skb_queue_purge(&port->bc_queue); + + while ((skb = __skb_dequeue(&port->bc_queue))) { + const struct macvlan_dev *src = MACVLAN_SKB_CB(skb)->src; + + if (src) + dev_put(src->dev); + + kfree_skb(skb); + } kfree_rcu(port, rcu); }