From mboxrd@z Thu Jan 1 00:00:00 1970 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=-9.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=unavailable 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 C8DBAC43603 for ; Wed, 4 Dec 2019 18:23:12 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 9C7012073B for ; Wed, 4 Dec 2019 18:23:12 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1575483792; bh=kqpzJnTxRpyBYOpXv54CkIzJJid5vTn2KtSckSJ5ySM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=zw09uTcVkCeQDlvWyq2PBdkElzOK2hyd3Ax+RzBFGKuIyqNNuerFLv+NEsMiDOrB5 4C2a08YKwaisqe89uDyj1nU6BPuHQse+HnSdZwlAuykUXQiJpOYiPs1eOKtPucA4/l Y8II9qwbPZ3yitilU7MfYSqYoOsh+sknNOmseOZU= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730193AbfLDSE3 (ORCPT ); Wed, 4 Dec 2019 13:04:29 -0500 Received: from mail.kernel.org ([198.145.29.99]:49276 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730154AbfLDSEO (ORCPT ); Wed, 4 Dec 2019 13:04:14 -0500 Received: from localhost (unknown [217.68.49.72]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 8A7AF20675; Wed, 4 Dec 2019 18:04:13 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1575482653; bh=kqpzJnTxRpyBYOpXv54CkIzJJid5vTn2KtSckSJ5ySM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=FupoDx1cisAZbV9EoC2phTzbcgYX21xO/PGr+8z51Gvmr0+CwsoK/3veyc0iQIlbc HWWOdfPuJNUqoFogMYM7gTgal3ZgNGxgcqKCQydNez5mP2qjb4zuMRz8BmdqUAr3f7 4/XcDbHpN+fk8aN/OlFjyORbexRYL9JN5oUQ4MbQ= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Petr Machata , "David S. Miller" , Sasha Levin Subject: [PATCH 4.14 081/209] vxlan: Fix error path in __vxlan_dev_create() Date: Wed, 4 Dec 2019 18:54:53 +0100 Message-Id: <20191204175327.105634330@linuxfoundation.org> X-Mailer: git-send-email 2.24.0 In-Reply-To: <20191204175321.609072813@linuxfoundation.org> References: <20191204175321.609072813@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Petr Machata [ Upstream commit 6db9246871394b3a136cd52001a0763676563840 ] When a failure occurs in rtnl_configure_link(), the current code calls unregister_netdevice() to roll back the earlier call to register_netdevice(), and jumps to errout, which calls vxlan_fdb_destroy(). However unregister_netdevice() calls transitively ndo_uninit, which is vxlan_uninit(), and that already takes care of deleting the default FDB entry by calling vxlan_fdb_delete_default(). Since the entry added earlier in __vxlan_dev_create() is exactly the default entry, the cleanup code in the errout block always leads to double free and thus a panic. Besides, since vxlan_fdb_delete_default() always destroys the FDB entry with notification enabled, the deletion of the default entry is notified even before the addition was notified. Instead, move the unregister_netdevice() call after the manual destroy, which solves both problems. Fixes: 0241b836732f ("vxlan: fix default fdb entry netlink notify ordering during netdev create") Signed-off-by: Petr Machata Signed-off-by: David S. Miller Signed-off-by: Sasha Levin --- drivers/net/vxlan.c | 13 ++++++++++--- 1 file changed, 10 insertions(+), 3 deletions(-) diff --git a/drivers/net/vxlan.c b/drivers/net/vxlan.c index 6d26bbd190dd6..153a81ece9fe4 100644 --- a/drivers/net/vxlan.c +++ b/drivers/net/vxlan.c @@ -3217,6 +3217,7 @@ static int __vxlan_dev_create(struct net *net, struct net_device *dev, struct vxlan_net *vn = net_generic(net, vxlan_net_id); struct vxlan_dev *vxlan = netdev_priv(dev); struct vxlan_fdb *f = NULL; + bool unregister = false; int err; err = vxlan_dev_configure(net, dev, conf, false, extack); @@ -3242,12 +3243,11 @@ static int __vxlan_dev_create(struct net *net, struct net_device *dev, err = register_netdevice(dev); if (err) goto errout; + unregister = true; err = rtnl_configure_link(dev, NULL); - if (err) { - unregister_netdevice(dev); + if (err) goto errout; - } /* notify default fdb entry */ if (f) @@ -3255,9 +3255,16 @@ static int __vxlan_dev_create(struct net *net, struct net_device *dev, list_add(&vxlan->next, &vn->vxlan_list); return 0; + errout: + /* unregister_netdevice() destroys the default FDB entry with deletion + * notification. But the addition notification was not sent yet, so + * destroy the entry by hand here. + */ if (f) vxlan_fdb_destroy(vxlan, f, false); + if (unregister) + unregister_netdevice(dev); return err; } -- 2.20.1