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=-6.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,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 7A377C433DF for ; Mon, 18 May 2020 17:42:50 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 5A98920657 for ; Mon, 18 May 2020 17:42:50 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1589823770; bh=P0lxkl9s3GlC3cewuWXxg05Kz+tb30Ge+n4wF50XGi4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=Q4JK/jxaWiPVX0/q7svAq0sNfUaJp2BlftD5Reiv/RmkuIn09TYgiDa1XWAOXQYeS Y1XURtd1SIvtRZ9HFLYO9f/WIOr3lWXf1b3Ba1stXTljy/vK59L43f4LQG4w1O6/+y 5R1c/D8MrWzqpZCoiZhDYNPF5P/H4oGF/ycCtVho= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729474AbgERRmt (ORCPT ); Mon, 18 May 2020 13:42:49 -0400 Received: from mail.kernel.org ([198.145.29.99]:39890 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728943AbgERRmq (ORCPT ); Mon, 18 May 2020 13:42:46 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (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 80FFC20657; Mon, 18 May 2020 17:42:45 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1589823766; bh=P0lxkl9s3GlC3cewuWXxg05Kz+tb30Ge+n4wF50XGi4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=sjuPYOiMkAcmdkcz3lvrPdnoY/8Kw1BXTIK8BRtJDPERlQetHym2Mq+ivo1idniLB EWeOoVPbC1Ck2cSG1eha2FjwuZtp45hGhE0kuP1cz7Ltw6m8ceSShLMrQbmpV2r4zz QyUqVQZYupJk2ZCoDrI6O6BY2VF6a05SLoUGt1/M= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Eric Dumazet , syzbot , Cong Wang , "David S. Miller" Subject: [PATCH 4.9 07/90] sch_choke: avoid potential panic in choke_reset() Date: Mon, 18 May 2020 19:35:45 +0200 Message-Id: <20200518173452.682172408@linuxfoundation.org> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20200518173450.930655662@linuxfoundation.org> References: <20200518173450.930655662@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Eric Dumazet [ Upstream commit 8738c85c72b3108c9b9a369a39868ba5f8e10ae0 ] If choke_init() could not allocate q->tab, we would crash later in choke_reset(). BUG: KASAN: null-ptr-deref in memset include/linux/string.h:366 [inline] BUG: KASAN: null-ptr-deref in choke_reset+0x208/0x340 net/sched/sch_choke.c:326 Write of size 8 at addr 0000000000000000 by task syz-executor822/7022 CPU: 1 PID: 7022 Comm: syz-executor822 Not tainted 5.7.0-rc1-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x188/0x20d lib/dump_stack.c:118 __kasan_report.cold+0x5/0x4d mm/kasan/report.c:515 kasan_report+0x33/0x50 mm/kasan/common.c:625 check_memory_region_inline mm/kasan/generic.c:187 [inline] check_memory_region+0x141/0x190 mm/kasan/generic.c:193 memset+0x20/0x40 mm/kasan/common.c:85 memset include/linux/string.h:366 [inline] choke_reset+0x208/0x340 net/sched/sch_choke.c:326 qdisc_reset+0x6b/0x520 net/sched/sch_generic.c:910 dev_deactivate_queue.constprop.0+0x13c/0x240 net/sched/sch_generic.c:1138 netdev_for_each_tx_queue include/linux/netdevice.h:2197 [inline] dev_deactivate_many+0xe2/0xba0 net/sched/sch_generic.c:1195 dev_deactivate+0xf8/0x1c0 net/sched/sch_generic.c:1233 qdisc_graft+0xd25/0x1120 net/sched/sch_api.c:1051 tc_modify_qdisc+0xbab/0x1a00 net/sched/sch_api.c:1670 rtnetlink_rcv_msg+0x44e/0xad0 net/core/rtnetlink.c:5454 netlink_rcv_skb+0x15a/0x410 net/netlink/af_netlink.c:2469 netlink_unicast_kernel net/netlink/af_netlink.c:1303 [inline] netlink_unicast+0x537/0x740 net/netlink/af_netlink.c:1329 netlink_sendmsg+0x882/0xe10 net/netlink/af_netlink.c:1918 sock_sendmsg_nosec net/socket.c:652 [inline] sock_sendmsg+0xcf/0x120 net/socket.c:672 ____sys_sendmsg+0x6bf/0x7e0 net/socket.c:2362 ___sys_sendmsg+0x100/0x170 net/socket.c:2416 __sys_sendmsg+0xec/0x1b0 net/socket.c:2449 do_syscall_64+0xf6/0x7d0 arch/x86/entry/common.c:295 Fixes: 77e62da6e60c ("sch_choke: drop all packets in queue during reset") Signed-off-by: Eric Dumazet Reported-by: syzbot Cc: Cong Wang Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- net/sched/sch_choke.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) --- a/net/sched/sch_choke.c +++ b/net/sched/sch_choke.c @@ -382,7 +382,8 @@ static void choke_reset(struct Qdisc *sc sch->q.qlen = 0; sch->qstats.backlog = 0; - memset(q->tab, 0, (q->tab_mask + 1) * sizeof(struct sk_buff *)); + if (q->tab) + memset(q->tab, 0, (q->tab_mask + 1) * sizeof(struct sk_buff *)); q->head = q->tail = 0; red_restart(&q->vars); }