From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Ignacy Gawedzki , Cong Wang , "David S. Miller" Subject: [PATCH 3.10 03/62] rtnetlink: call ->dellink on failure when ->newlink exists Date: Mon, 16 Mar 2015 15:09:20 +0100 Message-Id: <20150316140933.318957293@linuxfoundation.org> In-Reply-To: <20150316140933.139548981@linuxfoundation.org> References: <20150316140933.139548981@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-15 Sender: linux-kernel-owner@vger.kernel.org List-ID: 3.10-stable review patch. If anyone has any objections, please let me know. ------------------ From: WANG Cong [ Upstream commit 7afb8886a05be68e376655539a064ec672de8a8e ] Ignacy reported that when eth0 is down and add a vlan device on top of it like: ip link add link eth0 name eth0.1 up type vlan id 1 We will get a refcount leak: unregister_netdevice: waiting for eth0.1 to become free. Usage count = 2 The problem is when rtnl_configure_link() fails in rtnl_newlink(), we simply call unregister_device(), but for stacked device like vlan, we almost do nothing when we unregister the upper device, more work is done when we unregister the lower device, so call its ->dellink(). Reported-by: Ignacy Gawedzki Signed-off-by: Cong Wang Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- net/core/rtnetlink.c | 12 ++++++++++-- 1 file changed, 10 insertions(+), 2 deletions(-) --- a/net/core/rtnetlink.c +++ b/net/core/rtnetlink.c @@ -1851,8 +1851,16 @@ replay: goto out; err = rtnl_configure_link(dev, ifm); - if (err < 0) - unregister_netdevice(dev); + if (err < 0) { + if (ops->newlink) { + LIST_HEAD(list_kill); + + ops->dellink(dev, &list_kill); + unregister_netdevice_many(&list_kill); + } else { + unregister_netdevice(dev); + } + } out: put_net(dest_net); return err;