From patchwork Wed Jun 26 07:29:54 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Zefan Li X-Patchwork-Id: 254587 X-Patchwork-Delegate: davem@davemloft.net Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 48B1A2C0092 for ; Wed, 26 Jun 2013 17:30:29 +1000 (EST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751728Ab3FZHaI (ORCPT ); Wed, 26 Jun 2013 03:30:08 -0400 Received: from szxga01-in.huawei.com ([119.145.14.64]:4734 "EHLO szxga01-in.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750843Ab3FZHaG (ORCPT ); Wed, 26 Jun 2013 03:30:06 -0400 Received: from 172.24.2.119 (EHLO szxeml212-edg.china.huawei.com) ([172.24.2.119]) by szxrg01-dlp.huawei.com (MOS 4.3.4-GA FastPath queued) with ESMTP id BEJ39288; Wed, 26 Jun 2013 15:30:04 +0800 (CST) Received: from SZXEML412-HUB.china.huawei.com (10.82.67.91) by szxeml212-edg.china.huawei.com (172.24.2.181) with Microsoft SMTP Server (TLS) id 14.1.323.7; Wed, 26 Jun 2013 15:30:01 +0800 Received: from [10.135.68.215] (10.135.68.215) by smtpscn.huawei.com (10.82.67.91) with Microsoft SMTP Server (TLS) id 14.1.323.7; Wed, 26 Jun 2013 15:29:59 +0800 Message-ID: <51CA9872.5050700@huawei.com> Date: Wed, 26 Jun 2013 15:29:54 +0800 From: Li Zefan User-Agent: Mozilla/5.0 (Windows NT 6.1; rv:17.0) Gecko/20130509 Thunderbird/17.0.6 MIME-Version: 1.0 To: David Miller CC: LKML , Subject: [PATCH 1/2] dlci: acquire rtnl_lock before calling __dev_get_by_name() X-Originating-IP: [10.135.68.215] X-CFilter-Loop: Reflected Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org Otherwise the net device returned can be freed at anytime. Signed-off-by: Li Zefan Cc: stable@vger.kernel.org --- drivers/net/wan/dlci.c | 14 +++++++++----- 1 file changed, 9 insertions(+), 5 deletions(-) diff --git a/drivers/net/wan/dlci.c b/drivers/net/wan/dlci.c index 147614e..1f6e053 100644 --- a/drivers/net/wan/dlci.c +++ b/drivers/net/wan/dlci.c @@ -385,20 +385,24 @@ static int dlci_del(struct dlci_add *dlci) struct net_device *master, *slave; int err; + rtnl_lock(); + /* validate slave device */ master = __dev_get_by_name(&init_net, dlci->devname); - if (!master) - return -ENODEV; + if (!master) { + err = -ENODEV; + goto out; + } if (netif_running(master)) { - return -EBUSY; + err = -EBUSY; + goto out; } dlp = netdev_priv(master); slave = dlp->slave; flp = netdev_priv(slave); - rtnl_lock(); err = (*flp->deassoc)(slave, master); if (!err) { list_del(&dlp->list); @@ -407,8 +411,8 @@ static int dlci_del(struct dlci_add *dlci) dev_put(slave); } +out: rtnl_unlock(); - return err; }