From patchwork Tue Jun 22 03:09:29 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Di Zhu X-Patchwork-Id: 466320 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-16.7 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI, SPF_HELO_NONE, SPF_PASS, URIBL_BLOCKED, USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 54727C2B9F4 for ; Tue, 22 Jun 2021 03:09:41 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 2E7CC610EA for ; Tue, 22 Jun 2021 03:09:41 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230152AbhFVDLz (ORCPT ); Mon, 21 Jun 2021 23:11:55 -0400 Received: from szxga01-in.huawei.com ([45.249.212.187]:11077 "EHLO szxga01-in.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229904AbhFVDLy (ORCPT ); Mon, 21 Jun 2021 23:11:54 -0400 Received: from dggemv703-chm.china.huawei.com (unknown [172.30.72.56]) by szxga01-in.huawei.com (SkyGuard) with ESMTP id 4G8BBP5YG5zZgZY; Tue, 22 Jun 2021 11:06:37 +0800 (CST) Received: from dggpemm500021.china.huawei.com (7.185.36.109) by dggemv703-chm.china.huawei.com (10.3.19.46) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2176.2; Tue, 22 Jun 2021 11:09:37 +0800 Received: from DESKTOP-9883QJJ.china.huawei.com (10.136.114.155) by dggpemm500021.china.huawei.com (7.185.36.109) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2176.2; Tue, 22 Jun 2021 11:09:37 +0800 From: zhudi To: , , , CC: , , Subject: [PATCH] bonding: avoid adding slave device with IFF_MASTER flag Date: Tue, 22 Jun 2021 11:09:29 +0800 Message-ID: <20210622030929.51295-1-zhudi21@huawei.com> X-Mailer: git-send-email 2.27.0 MIME-Version: 1.0 X-Originating-IP: [10.136.114.155] X-ClientProxiedBy: dggems706-chm.china.huawei.com (10.3.19.183) To dggpemm500021.china.huawei.com (7.185.36.109) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org From: Di Zhu The following steps will definitely cause the kernel to crash: ip link add vrf1 type vrf table 1 modprobe bonding.ko max_bonds=1 echo "+vrf1" >/sys/class/net/bond0/bonding/slaves rmmod bonding The root cause is that: When the VRF is added to the slave device, it will fail, and some cleaning work will be done. because VRF device has IFF_MASTER flag, cleanup process will not clear the IFF_BONDING flag. Then, when we unload the bonding module, unregister_netdevice_notifier() will treat the VRF device as a bond master device and treat netdev_priv() as struct bonding{} which actually is struct net_vrf{}. By analyzing the processing logic of bond_enslave(), it seems that it is not allowed to add the slave device with the IFF_MASTER flag, so we need to add a code check for this situation. Signed-off-by: Di Zhu --- drivers/net/bonding/bond_main.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/drivers/net/bonding/bond_main.c b/drivers/net/bonding/bond_main.c index c5a646d06102..16840c9bc00d 100644 --- a/drivers/net/bonding/bond_main.c +++ b/drivers/net/bonding/bond_main.c @@ -1601,6 +1601,12 @@ int bond_enslave(struct net_device *bond_dev, struct net_device *slave_dev, int link_reporting; int res = 0, i; + if (slave_dev->flags & IFF_MASTER) { + netdev_err(bond_dev, + "Error: Device with IFF_MASTER cannot be enslaved\n"); + return -EPERM; + } + if (!bond->params.use_carrier && slave_dev->ethtool_ops->get_link == NULL && slave_ops->ndo_do_ioctl == NULL) {