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=-3.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED 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 94839C7112A for ; Sun, 14 Oct 2018 15:48:28 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 693B120645 for ; Sun, 14 Oct 2018 15:48:28 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 693B120645 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=decadent.org.uk Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729522AbeJNX3u (ORCPT ); Sun, 14 Oct 2018 19:29:50 -0400 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:37327 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728128AbeJNX3t (ORCPT ); Sun, 14 Oct 2018 19:29:49 -0400 Received: from [2a02:8011:400e:2:cbab:f00:c93f:614] (helo=deadeye) by shadbolt.decadent.org.uk with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.84_2) (envelope-from ) id 1gBiM6-0004cf-9R; Sun, 14 Oct 2018 16:30:58 +0100 Received: from ben by deadeye with local (Exim 4.91) (envelope-from ) id 1gBiLR-0000J3-KN; Sun, 14 Oct 2018 16:30:17 +0100 Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, "Eric Dumazet" , "David S. Miller" , "syzbot" Date: Sun, 14 Oct 2018 16:25:41 +0100 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) Subject: [PATCH 3.16 122/366] net: fix uninit-value in __hw_addr_add_ex() In-Reply-To: X-SA-Exim-Connect-IP: 2a02:8011:400e:2:cbab:f00:c93f:614 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.16.60-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Eric Dumazet commit 77d36398d99f2565c0a8d43a86fd520a82e64bb8 upstream. syzbot complained : BUG: KMSAN: uninit-value in memcmp+0x119/0x180 lib/string.c:861 CPU: 0 PID: 3 Comm: kworker/0:0 Not tainted 4.16.0+ #82 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: ipv6_addrconf addrconf_dad_work Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0x185/0x1d0 lib/dump_stack.c:53 kmsan_report+0x142/0x240 mm/kmsan/kmsan.c:1067 __msan_warning_32+0x6c/0xb0 mm/kmsan/kmsan_instr.c:676 memcmp+0x119/0x180 lib/string.c:861 __hw_addr_add_ex net/core/dev_addr_lists.c:60 [inline] __dev_mc_add+0x1c2/0x8e0 net/core/dev_addr_lists.c:670 dev_mc_add+0x6d/0x80 net/core/dev_addr_lists.c:687 igmp6_group_added+0x2db/0xa00 net/ipv6/mcast.c:662 ipv6_dev_mc_inc+0xe9e/0x1130 net/ipv6/mcast.c:914 addrconf_join_solict net/ipv6/addrconf.c:2078 [inline] addrconf_dad_begin net/ipv6/addrconf.c:3828 [inline] addrconf_dad_work+0x427/0x2150 net/ipv6/addrconf.c:3954 process_one_work+0x12c6/0x1f60 kernel/workqueue.c:2113 worker_thread+0x113c/0x24f0 kernel/workqueue.c:2247 kthread+0x539/0x720 kernel/kthread.c:239 Fixes: f001fde5eadd ("net: introduce a list of device addresses dev_addr_list (v6)") Signed-off-by: Eric Dumazet Reported-by: syzbot Signed-off-by: David S. Miller Signed-off-by: Ben Hutchings --- net/core/dev_addr_lists.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) --- a/net/core/dev_addr_lists.c +++ b/net/core/dev_addr_lists.c @@ -57,8 +57,8 @@ static int __hw_addr_add_ex(struct netde return -EINVAL; list_for_each_entry(ha, &list->list, list) { - if (!memcmp(ha->addr, addr, addr_len) && - ha->type == addr_type) { + if (ha->type == addr_type && + !memcmp(ha->addr, addr, addr_len)) { if (global) { /* check if addr is already used as global */ if (ha->global_use)