From patchwork Mon Jul 12 06:10:08 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg Kroah-Hartman X-Patchwork-Id: 476305 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=-19.4 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,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 7E53EC07E99 for ; Mon, 12 Jul 2021 06:24:17 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 69662610A6 for ; Mon, 12 Jul 2021 06:24:17 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235013AbhGLG1C (ORCPT ); Mon, 12 Jul 2021 02:27:02 -0400 Received: from mail.kernel.org ([198.145.29.99]:46224 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234965AbhGLG0G (ORCPT ); Mon, 12 Jul 2021 02:26:06 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 43E9461178; Mon, 12 Jul 2021 06:23:00 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1626070980; bh=y0xC0LgeNQcMN6qT+Su5XzN9BfAy6LsTv8SsWTEvHKM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=t0NX5FalWRL8/emqaz5SVVsGKXpLUB0v1IDXksq4+lZJSvzew17Viel1gYv8ywbey ts4eyEnPDHwamnniLDXiQ3GIbwWmSiuoYiREbOSX4YV9JB4fy8P0TZB3hj3jeKtvxk aD324Tana3aLz+BC9S996mWFtvw8J+SKY9BsP/Ow= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Eric Dumazet , syzbot , "David S. Miller" , Sasha Levin Subject: [PATCH 5.4 224/348] vxlan: add missing rcu_read_lock() in neigh_reduce() Date: Mon, 12 Jul 2021 08:10:08 +0200 Message-Id: <20210712060731.566650211@linuxfoundation.org> X-Mailer: git-send-email 2.32.0 In-Reply-To: <20210712060659.886176320@linuxfoundation.org> References: <20210712060659.886176320@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Eric Dumazet [ Upstream commit 85e8b032d6ebb0f698a34dd22c2f13443d905888 ] syzbot complained in neigh_reduce(), because rcu_read_lock_bh() is treated differently than rcu_read_lock() WARNING: suspicious RCU usage 5.13.0-rc6-syzkaller #0 Not tainted ----------------------------- include/net/addrconf.h:313 suspicious rcu_dereference_check() usage! other info that might help us debug this: rcu_scheduler_active = 2, debug_locks = 1 3 locks held by kworker/0:0/5: #0: ffff888011064d38 ((wq_completion)events){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff888011064d38 ((wq_completion)events){+.+.}-{0:0}, at: atomic64_set include/asm-generic/atomic-instrumented.h:856 [inline] #0: ffff888011064d38 ((wq_completion)events){+.+.}-{0:0}, at: atomic_long_set include/asm-generic/atomic-long.h:41 [inline] #0: ffff888011064d38 ((wq_completion)events){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:617 [inline] #0: ffff888011064d38 ((wq_completion)events){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:644 [inline] #0: ffff888011064d38 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x871/0x1600 kernel/workqueue.c:2247 #1: ffffc90000ca7da8 ((work_completion)(&port->wq)){+.+.}-{0:0}, at: process_one_work+0x8a5/0x1600 kernel/workqueue.c:2251 #2: ffffffff8bf795c0 (rcu_read_lock_bh){....}-{1:2}, at: __dev_queue_xmit+0x1da/0x3130 net/core/dev.c:4180 stack backtrace: CPU: 0 PID: 5 Comm: kworker/0:0 Not tainted 5.13.0-rc6-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: events ipvlan_process_multicast Call Trace: __dump_stack lib/dump_stack.c:79 [inline] dump_stack+0x141/0x1d7 lib/dump_stack.c:120 __in6_dev_get include/net/addrconf.h:313 [inline] __in6_dev_get include/net/addrconf.h:311 [inline] neigh_reduce drivers/net/vxlan.c:2167 [inline] vxlan_xmit+0x34d5/0x4c30 drivers/net/vxlan.c:2919 __netdev_start_xmit include/linux/netdevice.h:4944 [inline] netdev_start_xmit include/linux/netdevice.h:4958 [inline] xmit_one net/core/dev.c:3654 [inline] dev_hard_start_xmit+0x1eb/0x920 net/core/dev.c:3670 __dev_queue_xmit+0x2133/0x3130 net/core/dev.c:4246 ipvlan_process_multicast+0xa99/0xd70 drivers/net/ipvlan/ipvlan_core.c:287 process_one_work+0x98d/0x1600 kernel/workqueue.c:2276 worker_thread+0x64c/0x1120 kernel/workqueue.c:2422 kthread+0x3b1/0x4a0 kernel/kthread.c:313 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294 Fixes: f564f45c4518 ("vxlan: add ipv6 proxy support") Signed-off-by: Eric Dumazet Reported-by: syzbot Signed-off-by: David S. Miller Signed-off-by: Sasha Levin --- drivers/net/vxlan.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/net/vxlan.c b/drivers/net/vxlan.c index 8443df79fabc..c5991e31c557 100644 --- a/drivers/net/vxlan.c +++ b/drivers/net/vxlan.c @@ -1995,6 +1995,7 @@ static int neigh_reduce(struct net_device *dev, struct sk_buff *skb, __be32 vni) struct neighbour *n; struct nd_msg *msg; + rcu_read_lock(); in6_dev = __in6_dev_get(dev); if (!in6_dev) goto out; @@ -2046,6 +2047,7 @@ static int neigh_reduce(struct net_device *dev, struct sk_buff *skb, __be32 vni) } out: + rcu_read_unlock(); consume_skb(skb); return NETDEV_TX_OK; }