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 2A4E4E7C4E7 for ; Wed, 4 Oct 2023 18:13:31 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S243945AbjJDSNd (ORCPT ); Wed, 4 Oct 2023 14:13:33 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58974 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S243982AbjJDSNb (ORCPT ); Wed, 4 Oct 2023 14:13:31 -0400 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 7F200C1 for ; Wed, 4 Oct 2023 11:13:28 -0700 (PDT) Received: by smtp.kernel.org (Postfix) with ESMTPSA id C4D43C433C8; Wed, 4 Oct 2023 18:13:27 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1696443208; bh=jW8WcbdaQVeddCVh2Q7WT2U5b0rqxkGhFdj+dtu8m4E=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=w9LKC8hMF8YuaAgLOABpW59ygjsbaB52p0Sucwak7Kqvi8cFrbvit+cuL5Ase/VKS fdz8TZoSkWWaaRqzmg1JtajrFqIxPzjswZ6bnnLNH+dGD07J+53rU9F59igVR+FTVX gQkTUuEPVIQPctFcyePX8fROdIhAjCw0dvvmjuHM= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Hangbin Liu , Ziyang Xuan , Jiri Pirko , Eric Dumazet , Paolo Abeni , Sasha Levin Subject: [PATCH 6.1 075/259] team: fix null-ptr-deref when team device type is changed Date: Wed, 4 Oct 2023 19:54:08 +0200 Message-ID: <20231004175220.824969298@linuxfoundation.org> X-Mailer: git-send-email 2.42.0 In-Reply-To: <20231004175217.404851126@linuxfoundation.org> References: <20231004175217.404851126@linuxfoundation.org> User-Agent: quilt/0.67 X-stable: review X-Patchwork-Hint: ignore MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org 6.1-stable review patch. If anyone has any objections, please let me know. ------------------ From: Ziyang Xuan [ Upstream commit 492032760127251e5540a5716a70996bacf2a3fd ] Get a null-ptr-deref bug as follows with reproducer [1]. BUG: kernel NULL pointer dereference, address: 0000000000000228 ... RIP: 0010:vlan_dev_hard_header+0x35/0x140 [8021q] ... Call Trace: ? __die+0x24/0x70 ? page_fault_oops+0x82/0x150 ? exc_page_fault+0x69/0x150 ? asm_exc_page_fault+0x26/0x30 ? vlan_dev_hard_header+0x35/0x140 [8021q] ? vlan_dev_hard_header+0x8e/0x140 [8021q] neigh_connected_output+0xb2/0x100 ip6_finish_output2+0x1cb/0x520 ? nf_hook_slow+0x43/0xc0 ? ip6_mtu+0x46/0x80 ip6_finish_output+0x2a/0xb0 mld_sendpack+0x18f/0x250 mld_ifc_work+0x39/0x160 process_one_work+0x1e6/0x3f0 worker_thread+0x4d/0x2f0 ? __pfx_worker_thread+0x10/0x10 kthread+0xe5/0x120 ? __pfx_kthread+0x10/0x10 ret_from_fork+0x34/0x50 ? __pfx_kthread+0x10/0x10 ret_from_fork_asm+0x1b/0x30 [1] $ teamd -t team0 -d -c '{"runner": {"name": "loadbalance"}}' $ ip link add name t-dummy type dummy $ ip link add link t-dummy name t-dummy.100 type vlan id 100 $ ip link add name t-nlmon type nlmon $ ip link set t-nlmon master team0 $ ip link set t-nlmon nomaster $ ip link set t-dummy up $ ip link set team0 up $ ip link set t-dummy.100 down $ ip link set t-dummy.100 master team0 When enslave a vlan device to team device and team device type is changed from non-ether to ether, header_ops of team device is changed to vlan_header_ops. That is incorrect and will trigger null-ptr-deref for vlan->real_dev in vlan_dev_hard_header() because team device is not a vlan device. Cache eth_header_ops in team_setup(), then assign cached header_ops to header_ops of team net device when its type is changed from non-ether to ether to fix the bug. Fixes: 1d76efe1577b ("team: add support for non-ethernet devices") Suggested-by: Hangbin Liu Reviewed-by: Hangbin Liu Signed-off-by: Ziyang Xuan Reviewed-by: Jiri Pirko Reviewed-by: Eric Dumazet Link: https://lore.kernel.org/r/20230918123011.1884401-1-william.xuanziyang@huawei.com Signed-off-by: Paolo Abeni Signed-off-by: Sasha Levin --- drivers/net/team/team.c | 10 +++++++++- include/linux/if_team.h | 2 ++ 2 files changed, 11 insertions(+), 1 deletion(-) diff --git a/drivers/net/team/team.c b/drivers/net/team/team.c index 921ca59822b0f..556b2d1cd2aca 100644 --- a/drivers/net/team/team.c +++ b/drivers/net/team/team.c @@ -2127,7 +2127,12 @@ static const struct ethtool_ops team_ethtool_ops = { static void team_setup_by_port(struct net_device *dev, struct net_device *port_dev) { - dev->header_ops = port_dev->header_ops; + struct team *team = netdev_priv(dev); + + if (port_dev->type == ARPHRD_ETHER) + dev->header_ops = team->header_ops_cache; + else + dev->header_ops = port_dev->header_ops; dev->type = port_dev->type; dev->hard_header_len = port_dev->hard_header_len; dev->needed_headroom = port_dev->needed_headroom; @@ -2174,8 +2179,11 @@ static int team_dev_type_check_change(struct net_device *dev, static void team_setup(struct net_device *dev) { + struct team *team = netdev_priv(dev); + ether_setup(dev); dev->max_mtu = ETH_MAX_MTU; + team->header_ops_cache = dev->header_ops; dev->netdev_ops = &team_netdev_ops; dev->ethtool_ops = &team_ethtool_ops; diff --git a/include/linux/if_team.h b/include/linux/if_team.h index 8de6b6e678295..34bcba5a70677 100644 --- a/include/linux/if_team.h +++ b/include/linux/if_team.h @@ -189,6 +189,8 @@ struct team { struct net_device *dev; /* associated netdevice */ struct team_pcpu_stats __percpu *pcpu_stats; + const struct header_ops *header_ops_cache; + struct mutex lock; /* used for overall locking, e.g. port lists write */ /* -- 2.40.1