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 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id D4892C433F5 for ; Mon, 25 Oct 2021 06:59:30 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id AF6DF61002 for ; Mon, 25 Oct 2021 06:59:30 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231432AbhJYHBv (ORCPT ); Mon, 25 Oct 2021 03:01:51 -0400 Received: from out30-42.freemail.mail.aliyun.com ([115.124.30.42]:55792 "EHLO out30-42.freemail.mail.aliyun.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231419AbhJYHBt (ORCPT ); Mon, 25 Oct 2021 03:01:49 -0400 X-Alimail-AntiSpam: AC=PASS;BC=-1|-1;BR=01201311R121e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=e01e04394;MF=hsiangkao@linux.alibaba.com;NM=1;PH=DS;RN=7;SR=0;TI=SMTPD_---0UtYQvGX_1635145164; Received: from B-P7TQMD6M-0146.local(mailfrom:hsiangkao@linux.alibaba.com fp:SMTPD_---0UtYQvGX_1635145164) by smtp.aliyun-inc.com(127.0.0.1); Mon, 25 Oct 2021 14:59:25 +0800 Date: Mon, 25 Oct 2021 14:59:23 +0800 From: Gao Xiang To: Dmitry Vyukov Cc: syzbot , chao@kernel.org, linux-erofs@lists.ozlabs.org, linux-kernel@vger.kernel.org, syzkaller-bugs@googlegroups.com, xiang@kernel.org Subject: Re: [syzbot] WARNING in z_erofs_lz4_decompress Message-ID: References: <000000000000b3586105cf0ff45e@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Dmitry, On Mon, Oct 25, 2021 at 08:55:51AM +0200, Dmitry Vyukov wrote: > On Mon, 25 Oct 2021 at 02:17, Gao Xiang wrote: > > > > Hi, > > > > On Sat, Oct 23, 2021 at 07:25:20PM -0700, syzbot wrote: > > > Hello, > > > > > > syzbot found the following issue on: > > > > > > HEAD commit: 60e8840126bd Add linux-next specific files for 20211018 > > > git tree: linux-next > > > console output: https://syzkaller.appspot.com/x/log.txt?x=125932af300000 > > > kernel config: https://syzkaller.appspot.com/x/.config?x=4bd44cafcda7632e > > > dashboard link: https://syzkaller.appspot.com/bug?extid=d8aaffc3719597e8cfb4 > > > compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2 > > > > > > Unfortunately, I don't have any reproducer for this issue yet. > > > > > > IMPORTANT: if you fix the issue, please add the following tag to the commit: > > > Reported-by: syzbot+d8aaffc3719597e8cfb4@syzkaller.appspotmail.com > > > > > > erofs: (device loop4): z_erofs_lz4_decompress_mem: failed to decompress -4100 in[4096, 0] out[9000] > > > ------------[ cut here ]------------ > > > WARNING: CPU: 1 PID: 9895 at fs/erofs/decompressor.c:230 z_erofs_lz4_decompress_mem fs/erofs/decompressor.c:227 [inline] > > > WARNING: CPU: 1 PID: 9895 at fs/erofs/decompressor.c:230 z_erofs_lz4_decompress+0x841/0x1400 fs/erofs/decompressor.c:289 > > > > If you fuzz compressed data, that is what you'd expect.. > > Hi Gao, > > If you mean this is not a kernel bug, then the code should not use WARN. > WARN if for kernel bugs and is recognized as such by all testing > systems and humans. > > Please fix it to use pr_err. If it's intended for the end user, pr_err > can also give a meaningful message and no stack trace (which is I > assume only huge clutter in this case). Thanks, I will submit a patch to address that. Thanks, Gao Xiang > > > > Thanks, > > Gao Xiang > > > > > Modules linked in: > > > CPU: 1 PID: 9895 Comm: kworker/u5:3 Not tainted 5.15.0-rc5-next-20211018-syzkaller #0 > > > Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 > > > Workqueue: erofs_unzipd z_erofs_decompressqueue_work > > > RIP: 0010:z_erofs_lz4_decompress_mem fs/erofs/decompressor.c:230 [inline] > > > RIP: 0010:z_erofs_lz4_decompress+0x841/0x1400 fs/erofs/decompressor.c:289 > > > Code: e9 03 80 3c 11 00 0f 85 8c 0a 00 00 41 56 48 8b 7d 00 45 89 e9 89 d9 48 c7 c2 20 eb fb 89 48 c7 c6 40 ed fb 89 e8 ee 5d 85 05 <0f> 0b 48 b8 00 00 00 00 00 fc ff df 48 8b 4c 24 08 5f 48 89 ca 48 > > > RSP: 0018:ffffc90001b3f718 EFLAGS: 00010286 > > > RAX: 0000000000000000 RBX: ffffffffffffeffc RCX: 0000000000000000 > > > RDX: ffff8880795b3a00 RSI: ffffffff815ef308 RDI: fffff52000367ed3 > > > RBP: ffffc90001b3f858 R08: 0000000000000063 R09: 0000000000000000 > > > R10: ffffffff815e90de R11: 0000000000000000 R12: 0000000000000000 > > > R13: 0000000000000000 R14: 0000000000002328 R15: 0000000000000000 > > > FS: 0000000000000000(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000 > > > CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 > > > CR2: 0000001b2ef25000 CR3: 000000002b3f7000 CR4: 00000000003506e0 > > > DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 > > > DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 > > > Call Trace: > > > > > > z_erofs_decompress_pcluster.isra.0+0x1389/0x2450 fs/erofs/zdata.c:977 > > > z_erofs_decompress_queue fs/erofs/zdata.c:1055 [inline] > > > z_erofs_decompressqueue_work+0xe0/0x170 fs/erofs/zdata.c:1066 > > > process_one_work+0x9b2/0x1690 kernel/workqueue.c:2297 > > > worker_thread+0x658/0x11f0 kernel/workqueue.c:2444 > > > kthread+0x405/0x4f0 kernel/kthread.c:327 > > > ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 > > > > > > > > > > > > --- > > > This report is generated by a bot. It may contain errors. > > > See https://goo.gl/tpsmEJ for more information about syzbot. > > > syzbot engineers can be reached at syzkaller@googlegroups.com. > > > > > > syzbot will keep track of this issue. See: > > > https://goo.gl/tpsmEJ#status for how to communicate with syzbot. 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 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8E63AC433F5 for ; Mon, 25 Oct 2021 06:59:56 +0000 (UTC) Received: from lists.ozlabs.org (lists.ozlabs.org [112.213.38.117]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id E4F7960FDC for ; Mon, 25 Oct 2021 06:59:55 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org E4F7960FDC Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linux.alibaba.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=lists.ozlabs.org Received: from boromir.ozlabs.org (localhost [IPv6:::1]) by lists.ozlabs.org (Postfix) with ESMTP id 4Hd5Rt3Htlz2yHJ for ; Mon, 25 Oct 2021 17:59:54 +1100 (AEDT) Authentication-Results: lists.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=linux.alibaba.com (client-ip=115.124.30.45; helo=out30-45.freemail.mail.aliyun.com; envelope-from=hsiangkao@linux.alibaba.com; receiver=) Received: from out30-45.freemail.mail.aliyun.com (out30-45.freemail.mail.aliyun.com [115.124.30.45]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 4Hd5Rm01G5z2xX5 for ; Mon, 25 Oct 2021 17:59:43 +1100 (AEDT) X-Alimail-AntiSpam: AC=PASS; BC=-1|-1; BR=01201311R121e4; CH=green; DM=||false|; DS=||; FP=0|-1|-1|-1|0|-1|-1|-1; HT=e01e04394; MF=hsiangkao@linux.alibaba.com; NM=1; PH=DS; RN=7; SR=0; TI=SMTPD_---0UtYQvGX_1635145164; Received: from B-P7TQMD6M-0146.local(mailfrom:hsiangkao@linux.alibaba.com fp:SMTPD_---0UtYQvGX_1635145164) by smtp.aliyun-inc.com(127.0.0.1); Mon, 25 Oct 2021 14:59:25 +0800 Date: Mon, 25 Oct 2021 14:59:23 +0800 From: Gao Xiang To: Dmitry Vyukov Subject: Re: [syzbot] WARNING in z_erofs_lz4_decompress Message-ID: References: <000000000000b3586105cf0ff45e@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: X-BeenThere: linux-erofs@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Development of Linux EROFS file system List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: syzbot , syzkaller-bugs@googlegroups.com, linux-kernel@vger.kernel.org, linux-erofs@lists.ozlabs.org Errors-To: linux-erofs-bounces+linux-erofs=archiver.kernel.org@lists.ozlabs.org Sender: "Linux-erofs" Hi Dmitry, On Mon, Oct 25, 2021 at 08:55:51AM +0200, Dmitry Vyukov wrote: > On Mon, 25 Oct 2021 at 02:17, Gao Xiang wrote: > > > > Hi, > > > > On Sat, Oct 23, 2021 at 07:25:20PM -0700, syzbot wrote: > > > Hello, > > > > > > syzbot found the following issue on: > > > > > > HEAD commit: 60e8840126bd Add linux-next specific files for 20211018 > > > git tree: linux-next > > > console output: https://syzkaller.appspot.com/x/log.txt?x=125932af300000 > > > kernel config: https://syzkaller.appspot.com/x/.config?x=4bd44cafcda7632e > > > dashboard link: https://syzkaller.appspot.com/bug?extid=d8aaffc3719597e8cfb4 > > > compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2 > > > > > > Unfortunately, I don't have any reproducer for this issue yet. > > > > > > IMPORTANT: if you fix the issue, please add the following tag to the commit: > > > Reported-by: syzbot+d8aaffc3719597e8cfb4@syzkaller.appspotmail.com > > > > > > erofs: (device loop4): z_erofs_lz4_decompress_mem: failed to decompress -4100 in[4096, 0] out[9000] > > > ------------[ cut here ]------------ > > > WARNING: CPU: 1 PID: 9895 at fs/erofs/decompressor.c:230 z_erofs_lz4_decompress_mem fs/erofs/decompressor.c:227 [inline] > > > WARNING: CPU: 1 PID: 9895 at fs/erofs/decompressor.c:230 z_erofs_lz4_decompress+0x841/0x1400 fs/erofs/decompressor.c:289 > > > > If you fuzz compressed data, that is what you'd expect.. > > Hi Gao, > > If you mean this is not a kernel bug, then the code should not use WARN. > WARN if for kernel bugs and is recognized as such by all testing > systems and humans. > > Please fix it to use pr_err. If it's intended for the end user, pr_err > can also give a meaningful message and no stack trace (which is I > assume only huge clutter in this case). Thanks, I will submit a patch to address that. Thanks, Gao Xiang > > > > Thanks, > > Gao Xiang > > > > > Modules linked in: > > > CPU: 1 PID: 9895 Comm: kworker/u5:3 Not tainted 5.15.0-rc5-next-20211018-syzkaller #0 > > > Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 > > > Workqueue: erofs_unzipd z_erofs_decompressqueue_work > > > RIP: 0010:z_erofs_lz4_decompress_mem fs/erofs/decompressor.c:230 [inline] > > > RIP: 0010:z_erofs_lz4_decompress+0x841/0x1400 fs/erofs/decompressor.c:289 > > > Code: e9 03 80 3c 11 00 0f 85 8c 0a 00 00 41 56 48 8b 7d 00 45 89 e9 89 d9 48 c7 c2 20 eb fb 89 48 c7 c6 40 ed fb 89 e8 ee 5d 85 05 <0f> 0b 48 b8 00 00 00 00 00 fc ff df 48 8b 4c 24 08 5f 48 89 ca 48 > > > RSP: 0018:ffffc90001b3f718 EFLAGS: 00010286 > > > RAX: 0000000000000000 RBX: ffffffffffffeffc RCX: 0000000000000000 > > > RDX: ffff8880795b3a00 RSI: ffffffff815ef308 RDI: fffff52000367ed3 > > > RBP: ffffc90001b3f858 R08: 0000000000000063 R09: 0000000000000000 > > > R10: ffffffff815e90de R11: 0000000000000000 R12: 0000000000000000 > > > R13: 0000000000000000 R14: 0000000000002328 R15: 0000000000000000 > > > FS: 0000000000000000(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000 > > > CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 > > > CR2: 0000001b2ef25000 CR3: 000000002b3f7000 CR4: 00000000003506e0 > > > DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 > > > DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 > > > Call Trace: > > > > > > z_erofs_decompress_pcluster.isra.0+0x1389/0x2450 fs/erofs/zdata.c:977 > > > z_erofs_decompress_queue fs/erofs/zdata.c:1055 [inline] > > > z_erofs_decompressqueue_work+0xe0/0x170 fs/erofs/zdata.c:1066 > > > process_one_work+0x9b2/0x1690 kernel/workqueue.c:2297 > > > worker_thread+0x658/0x11f0 kernel/workqueue.c:2444 > > > kthread+0x405/0x4f0 kernel/kthread.c:327 > > > ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 > > > > > > > > > > > > --- > > > This report is generated by a bot. It may contain errors. > > > See https://goo.gl/tpsmEJ for more information about syzbot. > > > syzbot engineers can be reached at syzkaller@googlegroups.com. > > > > > > syzbot will keep track of this issue. See: > > > https://goo.gl/tpsmEJ#status for how to communicate with syzbot.