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=-7.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 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 A6F12C433E0 for ; Mon, 8 Jun 2020 08:02:49 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 85ED4206D5 for ; Mon, 8 Jun 2020 08:02:49 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729087AbgFHICs (ORCPT ); Mon, 8 Jun 2020 04:02:48 -0400 Received: from foss.arm.com ([217.140.110.172]:49430 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729070AbgFHICs (ORCPT ); Mon, 8 Jun 2020 04:02:48 -0400 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 68D1F1F1; Mon, 8 Jun 2020 01:02:47 -0700 (PDT) Received: from [192.168.1.84] (unknown [172.31.20.19]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id B17873F6CF; Mon, 8 Jun 2020 01:02:44 -0700 (PDT) Subject: Re: [x86] 24256c140e: dmesg.UBSAN:array-index-out-of-bounds_in_arch/x86/mm/dump_pagetables.c To: kernel test robot Cc: Stephen Rothwell , Jan Beulich , Andy Lutomirski , Borislav Petkov , Dave Hansen , Ingo Molnar , Peter Zijlstra , Thomas Gleixner , Andrew Morton , LKML , lkp@lists.01.org References: <20200607072749.GW12456@shao2-debian> From: Steven Price Message-ID: <2a7426e7-1331-4836-ddcc-5e117fe79b08@arm.com> Date: Mon, 8 Jun 2020 09:02:43 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.8.0 MIME-Version: 1.0 In-Reply-To: <20200607072749.GW12456@shao2-debian> Content-Type: text/plain; charset=windows-1252; format=flowed Content-Language: en-GB Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 07/06/2020 08:27, kernel test robot wrote: > Greeting, > > FYI, we noticed the following commit (built with gcc-9): > > commit: 24256c140e59c3431af4918fd4ec892102cbc2f3 ("x86: mm: ptdump: calculate effective permissions correctly") > https://git.kernel.org/cgit/linux/kernel/git/next/linux-next.git master This was reported earlier[1] by Qian Cai and I posted a fix[2]. Linus' tree has the fixed commit[3]. Steve [1] https://lore.kernel.org/lkml/20200522180741.GB1337@Qians-MacBook-Air.local/ [2] https://lore.kernel.org/linux-mm/430c8ab4-e7cd-6933-dde6-087fac6db872@arm.com/ [3] 1494e0c38ee9 ("x86: mm: ptdump: calculate effective permissions correctly") > > in testcase: boot > > on test machine: qemu-system-x86_64 -enable-kvm -cpu SandyBridge -smp 2 -m 8G > > caused below changes (please refer to attached dmesg/kmsg for entire log/backtrace): > > > > > If you fix the issue, kindly add following tag > Reported-by: kernel test robot > > > [ 8.785395] UBSAN: array-index-out-of-bounds in arch/x86/mm/dump_pagetables.c:285:27 > [ 8.787718] index -1 is out of range for type 'pgprotval_t [5]' > [ 8.789278] CPU: 1 PID: 1 Comm: swapper/0 Not tainted 5.7.0-rc7-00027-g24256c140e59c #1 > [ 8.791350] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-1 04/01/2014 > [ 8.793505] Call Trace: > [ 8.794221] dump_stack+0x6c/0x94 > [ 8.795140] ubsan_epilogue+0x8/0x3e > [ 8.796132] __ubsan_handle_out_of_bounds+0x48/0x53 > [ 8.797362] ? is_visible+0x2b/0x32 > [ 8.798231] ? atomic_try_cmpxchg+0x4c/0x57 > [ 8.799203] note_page+0x37/0x80b > [ 8.800138] ? __up_read+0x352/0x37b > [ 8.801124] ptdump_walk_pgd+0x57/0x60 > [ 8.802145] ptdump_walk_pgd_level_core+0x72/0x9f > [ 8.803369] ? ptdump_walk_pgd_level_debugfs+0x18/0x18 > [ 8.804613] ? ptdump_walk_pgd_level_core+0x9f/0x9f > [ 8.805779] ptdump_walk_pgd_level_checkwx+0x1d/0x21 > [ 8.806873] mark_rodata_ro+0x9f/0xa6 > [ 8.807821] ? rest_init+0x7f/0x164 > [ 8.808808] kernel_init+0x44/0xf7 > [ 8.809735] ? rest_init+0x164/0x164 > [ 8.810708] ret_from_fork+0x19/0x24 > > > To reproduce: > > # build kernel > cd linux > cp config-5.7.0-rc7-00027-g24256c140e59c .config > make HOSTCC=gcc-9 CC=gcc-9 ARCH=i386 olddefconfig prepare modules_prepare bzImage > > git clone https://github.com/intel/lkp-tests.git > cd lkp-tests > bin/lkp qemu -k job-script # job-script is attached in this email > > > > Thanks, > Rong Chen >