From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.kernel.org ([198.145.29.99]:54480 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S966408AbeEXJm4 (ORCPT ); Thu, 24 May 2018 05:42:56 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, syzbot+de73361ee4971b6e6f75@syzkaller.appspotmail.com, Hangbin Liu , Nikolay Aleksandrov , "David S. Miller" Subject: [PATCH 4.4 02/92] bridge: check iface upper dev when setting master via ioctl Date: Thu, 24 May 2018 11:37:39 +0200 Message-Id: <20180524093159.476457655@linuxfoundation.org> In-Reply-To: <20180524093159.286472249@linuxfoundation.org> References: <20180524093159.286472249@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: stable-owner@vger.kernel.org List-ID: 4.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Hangbin Liu [ Upstream commit e8238fc2bd7b4c3c7554fa2df067e796610212fc ] When we set a bond slave's master to bridge via ioctl, we only check the IFF_BRIDGE_PORT flag. Although we will find the slave's real master at netdev_master_upper_dev_link() later, it already does some settings and allocates some resources. It would be better to return as early as possible. v1 -> v2: use netdev_master_upper_dev_get() instead of netdev_has_any_upper_dev() to check if we have a master, because not all upper devs are masters, e.g. vlan device. Reported-by: syzbot+de73361ee4971b6e6f75@syzkaller.appspotmail.com Signed-off-by: Hangbin Liu Acked-by: Nikolay Aleksandrov Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- net/bridge/br_if.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) --- a/net/bridge/br_if.c +++ b/net/bridge/br_if.c @@ -456,8 +456,8 @@ int br_add_if(struct net_bridge *br, str if (dev->netdev_ops->ndo_start_xmit == br_dev_xmit) return -ELOOP; - /* Device is already being bridged */ - if (br_port_exists(dev)) + /* Device has master upper dev */ + if (netdev_master_upper_dev_get(dev)) return -EBUSY; /* No bridging devices that dislike that (e.g. wireless) */