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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 621ACC433EF for ; Mon, 14 Feb 2022 07:24:32 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237081AbiBNHYh (ORCPT ); Mon, 14 Feb 2022 02:24:37 -0500 Received: from mxb-00190b01.gslb.pphosted.com ([23.128.96.19]:38886 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231745AbiBNHYg (ORCPT ); Mon, 14 Feb 2022 02:24:36 -0500 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C6E9B593A2 for ; Sun, 13 Feb 2022 23:24:28 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 6270960ECF for ; Mon, 14 Feb 2022 07:24:28 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 1E092C340EB; Mon, 14 Feb 2022 07:24:26 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1644823467; bh=ihiHL4HtfuSUBp0VdUxx6+K095fAbXZW+UizYEOFCO4=; h=Subject:To:Cc:From:Date:From; b=VpTrpzNBQcL2lyDywNtP6zChvkZWeM+Qaxg3lvxbq4LwxmLEiIU68c+v2FY9Z6u5u utfB698AtZFjFaAXHTUAb/izCxEOHQAXdTmgNgwv7n8nkhAgiNRIOAmkjcg9e/O714 UhHKvITCtq8ZaFx+ZnB08dCEJPiq3xjinHEcgJcg= Subject: FAILED: patch "[PATCH] vlan: move dev_put into vlan_dev_uninit" failed to apply to 5.16-stable tree To: lucien.xin@gmail.com, davem@davemloft.net, shuali@redhat.com Cc: From: Date: Mon, 14 Feb 2022 08:24:12 +0100 Message-ID: <164482345221066@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=ANSI_X3.4-1968 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org The patch below does not apply to the 5.16-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to . thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From d6ff94afd90b0ce8d1715f8ef77d4347d7a7f2c0 Mon Sep 17 00:00:00 2001 From: Xin Long Date: Wed, 9 Feb 2022 03:19:56 -0500 Subject: [PATCH] vlan: move dev_put into vlan_dev_uninit Shuang Li reported an QinQ issue by simply doing: # ip link add dummy0 type dummy # ip link add link dummy0 name dummy0.1 type vlan id 1 # ip link add link dummy0.1 name dummy0.1.2 type vlan id 2 # rmmod 8021q unregister_netdevice: waiting for dummy0.1 to become free. Usage count = 1 When rmmods 8021q, all vlan devs are deleted from their real_dev's vlan grp and added into list_kill by unregister_vlan_dev(). dummy0.1 is unregistered before dummy0.1.2, as it's using for_each_netdev() in __rtnl_kill_links(). When unregisters dummy0.1, dummy0.1.2 is not unregistered in the event of NETDEV_UNREGISTER, as it's been deleted from dummy0.1's vlan grp. However, due to dummy0.1.2 still holding dummy0.1, dummy0.1 will keep waiting in netdev_wait_allrefs(), while dummy0.1.2 will never get unregistered and release dummy0.1, as it delays dev_put until calling dev->priv_destructor, vlan_dev_free(). This issue was introduced by Commit 563bcbae3ba2 ("net: vlan: fix a UAF in vlan_dev_real_dev()"), and this patch is to fix it by moving dev_put() into vlan_dev_uninit(), which is called after NETDEV_UNREGISTER event but before netdev_wait_allrefs(). Fixes: 563bcbae3ba2 ("net: vlan: fix a UAF in vlan_dev_real_dev()") Reported-by: Shuang Li Signed-off-by: Xin Long Signed-off-by: David S. Miller diff --git a/net/8021q/vlan_dev.c b/net/8021q/vlan_dev.c index e5d23e75572a..d1902828a18a 100644 --- a/net/8021q/vlan_dev.c +++ b/net/8021q/vlan_dev.c @@ -638,7 +638,12 @@ void vlan_dev_free_egress_priority(const struct net_device *dev) static void vlan_dev_uninit(struct net_device *dev) { + struct vlan_dev_priv *vlan = vlan_dev_priv(dev); + vlan_dev_free_egress_priority(dev); + + /* Get rid of the vlan's reference to real_dev */ + dev_put_track(vlan->real_dev, &vlan->dev_tracker); } static netdev_features_t vlan_dev_fix_features(struct net_device *dev, @@ -851,9 +856,6 @@ static void vlan_dev_free(struct net_device *dev) free_percpu(vlan->vlan_pcpu_stats); vlan->vlan_pcpu_stats = NULL; - - /* Get rid of the vlan's reference to real_dev */ - dev_put_track(vlan->real_dev, &vlan->dev_tracker); } void vlan_setup(struct net_device *dev)