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=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 7A4A0C10F14 for ; Sun, 6 Oct 2019 17:20:51 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 4D79020862 for ; Sun, 6 Oct 2019 17:20:51 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1570382451; bh=ulmBSzLUv9XyxKHcF6KYUj8glUpnldO0jiVn7QyKOig=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=Tv9TpnAtttbJMhnY0zJ+jdMkqUHoMufmWHxZhlZ4a1/xarEwe0BMdenaLgYiPgypw /mg5b6UvWM/vdkGtPKNoLUqL/b4tE/Eq3hnGgKe8K2Jpz+ZEvsbTeA3fQgqIBIFj+k 5j0rvPhNjrvEwZLyMLOMUBI8s5YABb4Zs96udv0c= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727345AbfJFRUu (ORCPT ); Sun, 6 Oct 2019 13:20:50 -0400 Received: from mail.kernel.org ([198.145.29.99]:45880 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727329AbfJFRUr (ORCPT ); Sun, 6 Oct 2019 13:20:47 -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 8BAB32080F; Sun, 6 Oct 2019 17:20:46 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1570382447; bh=ulmBSzLUv9XyxKHcF6KYUj8glUpnldO0jiVn7QyKOig=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=dasxzwizSGuQldDs1VCH51TKG237Vq7Lsl7sN1Q/Yd1/m+Lec5ZVX81kdfn5Q8eem Vv45x5RcChUK12nCTNppbx97Tvz43XZFsLyRuoeHR1yYGQPwoG9V+YQTIVDqqe5PLG lzwlfvX+zh7Z9wXjtq5eGZeAZiW43yU/imgcOkEg= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Eric Dumazet , syzbot , "David S. Miller" Subject: [PATCH 4.4 33/36] sch_cbq: validate TCA_CBQ_WRROPT to avoid crash Date: Sun, 6 Oct 2019 19:19:15 +0200 Message-Id: <20191006171100.370288203@linuxfoundation.org> X-Mailer: git-send-email 2.23.0 In-Reply-To: <20191006171038.266461022@linuxfoundation.org> References: <20191006171038.266461022@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: Eric Dumazet [ Upstream commit e9789c7cc182484fc031fd88097eb14cb26c4596 ] syzbot reported a crash in cbq_normalize_quanta() caused by an out of range cl->priority. iproute2 enforces this check, but malicious users do not. kasan: CONFIG_KASAN_INLINE enabled kasan: GPF could be caused by NULL-ptr deref or user memory access general protection fault: 0000 [#1] SMP KASAN PTI Modules linked in: CPU: 1 PID: 26447 Comm: syz-executor.1 Not tainted 5.3+ #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:cbq_normalize_quanta.part.0+0x1fd/0x430 net/sched/sch_cbq.c:902 RSP: 0018:ffff8801a5c333b0 EFLAGS: 00010206 RAX: 0000000020000003 RBX: 00000000fffffff8 RCX: ffffc9000712f000 RDX: 00000000000043bf RSI: ffffffff83be8962 RDI: 0000000100000018 RBP: ffff8801a5c33420 R08: 000000000000003a R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 00000000000002ef R13: ffff88018da95188 R14: dffffc0000000000 R15: 0000000000000015 FS: 00007f37d26b1700(0000) GS:ffff8801dad00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00000000004c7cec CR3: 00000001bcd0a006 CR4: 00000000001626f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: [] cbq_normalize_quanta include/net/pkt_sched.h:27 [inline] [] cbq_addprio net/sched/sch_cbq.c:1097 [inline] [] cbq_set_wrr+0x2d7/0x450 net/sched/sch_cbq.c:1115 [] cbq_change_class+0x987/0x225b net/sched/sch_cbq.c:1537 [] tc_ctl_tclass+0x555/0xcd0 net/sched/sch_api.c:2329 [] rtnetlink_rcv_msg+0x485/0xc10 net/core/rtnetlink.c:5248 [] netlink_rcv_skb+0x17a/0x460 net/netlink/af_netlink.c:2510 [] rtnetlink_rcv+0x1d/0x30 net/core/rtnetlink.c:5266 [] netlink_unicast_kernel net/netlink/af_netlink.c:1324 [inline] [] netlink_unicast+0x536/0x720 net/netlink/af_netlink.c:1350 [] netlink_sendmsg+0x89a/0xd50 net/netlink/af_netlink.c:1939 [] sock_sendmsg_nosec net/socket.c:673 [inline] [] sock_sendmsg+0x12e/0x170 net/socket.c:684 [] ___sys_sendmsg+0x81d/0x960 net/socket.c:2359 [] __sys_sendmsg+0x105/0x1d0 net/socket.c:2397 [] SYSC_sendmsg net/socket.c:2406 [inline] [] SyS_sendmsg+0x29/0x30 net/socket.c:2404 [] do_syscall_64+0x528/0x770 arch/x86/entry/common.c:305 [] entry_SYSCALL_64_after_hwframe+0x42/0xb7 Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Eric Dumazet Reported-by: syzbot Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- net/sched/sch_cbq.c | 27 ++++++++++++++++++++++----- 1 file changed, 22 insertions(+), 5 deletions(-) --- a/net/sched/sch_cbq.c +++ b/net/sched/sch_cbq.c @@ -1340,6 +1340,26 @@ static const struct nla_policy cbq_polic [TCA_CBQ_POLICE] = { .len = sizeof(struct tc_cbq_police) }, }; +static int cbq_opt_parse(struct nlattr *tb[TCA_CBQ_MAX + 1], struct nlattr *opt) +{ + int err; + + if (!opt) + return -EINVAL; + + err = nla_parse_nested(tb, TCA_CBQ_MAX, opt, cbq_policy); + if (err < 0) + return err; + + if (tb[TCA_CBQ_WRROPT]) { + const struct tc_cbq_wrropt *wrr = nla_data(tb[TCA_CBQ_WRROPT]); + + if (wrr->priority > TC_CBQ_MAXPRIO) + err = -EINVAL; + } + return err; +} + static int cbq_init(struct Qdisc *sch, struct nlattr *opt) { struct cbq_sched_data *q = qdisc_priv(sch); @@ -1347,7 +1367,7 @@ static int cbq_init(struct Qdisc *sch, s struct tc_ratespec *r; int err; - err = nla_parse_nested(tb, TCA_CBQ_MAX, opt, cbq_policy); + err = cbq_opt_parse(tb, opt); if (err < 0) return err; @@ -1728,10 +1748,7 @@ cbq_change_class(struct Qdisc *sch, u32 struct cbq_class *parent; struct qdisc_rate_table *rtab = NULL; - if (opt == NULL) - return -EINVAL; - - err = nla_parse_nested(tb, TCA_CBQ_MAX, opt, cbq_policy); + err = cbq_opt_parse(tb, opt); if (err < 0) return err;