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=-0.4 required=3.0 tests=FROM_LOCAL_HEX, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED autolearn=no 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 85890CA9EA0 for ; Fri, 25 Oct 2019 08:38:14 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 64E2B21D82 for ; Fri, 25 Oct 2019 08:38:14 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2407271AbfJYIiN (ORCPT ); Fri, 25 Oct 2019 04:38:13 -0400 Received: from mail-il1-f199.google.com ([209.85.166.199]:40562 "EHLO mail-il1-f199.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2404179AbfJYIiN (ORCPT ); Fri, 25 Oct 2019 04:38:13 -0400 Received: by mail-il1-f199.google.com with SMTP id x17so1592054ill.7 for ; Fri, 25 Oct 2019 01:38:13 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:date:message-id:subject:from:to; bh=Xx2ilS5o98N5EWeA3DS9BzkSPRq1qrT7n0PMAlOFbY8=; b=aEntqEcrgIj4/NSZEzeR4egOqZgsFZ78+SGP52/krXQaGIFldmz/0rEnEGVSvZGuZE X9Xu7ZJdnVMcwUZcGrwzOfl3nKCATS9vL7QEz5YS1L0uFuFP9FoyQ5WBD6PaVxDywJVI dNHdD/kihS/so4+q9kVTG1nooFEO5POd9mXBz+0QCwORIWlqN8Gd9DeBfiWcNarfBOrl h129+h00n0KleHZNLDvFfSZpq1lVZIZN59n7H4Mnz8sU06/s6DbmmWe/ajDM0bE34HUX T9uk9uatKo+avSHY1zxkWlYVlEwPnoxE+9kEYyQHDdODpjcDGXnIi1J6Dr0TZ8AyQcVL Iobw== X-Gm-Message-State: APjAAAXVhEbVJXSXzgh0p8Z49vccIoNYWJgvopliUKR7ItR7q91iMs6f +YiHYvsW25EtotCkraHzXjJ8ftlF70gWAVEtdZxhYXJkn6oo X-Google-Smtp-Source: APXvYqyGIgGMWwSwmp7dv/vinP8k9GbsPCnDljuS1bRDLNuHaYz7l+t+DoF01rQS0n34/MlnEOtAB3p6GxnPpYdNtOZM4CpXPBGR MIME-Version: 1.0 X-Received: by 2002:a02:a786:: with SMTP id e6mr135587jaj.29.1571992692688; Fri, 25 Oct 2019 01:38:12 -0700 (PDT) Date: Fri, 25 Oct 2019 01:38:12 -0700 X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <000000000000098bee0595b81273@google.com> Subject: KASAN: stack-out-of-bounds Read in finish_writeback_work From: syzbot To: linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, netdev@vger.kernel.org, syzkaller-bugs@googlegroups.com, viro@zeniv.linux.org.uk Content-Type: text/plain; charset="UTF-8"; format=flowed; delsp=yes Sender: linux-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org Hello, syzbot found the following crash on: HEAD commit: 05679ca6 xdp: Prevent overflow in devmap_hash cost calcula.. git tree: bpf console output: https://syzkaller.appspot.com/x/log.txt?x=12d37fcf600000 kernel config: https://syzkaller.appspot.com/x/.config?x=ebb95b9e9f5291dd dashboard link: https://syzkaller.appspot.com/bug?extid=357de617b97752833bd5 compiler: gcc (GCC) 9.0.0 20181231 (experimental) Unfortunately, I don't have any reproducer for this crash yet. IMPORTANT: if you fix the bug, please add the following tag to the commit: Reported-by: syzbot+357de617b97752833bd5@syzkaller.appspotmail.com ================================================================== BUG: KASAN: stack-out-of-bounds in finish_writeback_work.isra.0+0x11b/0x120 fs/fs-writeback.c:168 Read of size 8 at addr ffff88806f04f9c8 by task kworker/u4:2/33 CPU: 1 PID: 33 Comm: kworker/u4:2 Not tainted 5.4.0-rc1+ #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: writeback wb_workfn (flush-8:0) Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x172/0x1f0 lib/dump_stack.c:113 print_address_description.constprop.0.cold+0xd4/0x30b mm/kasan/report.c:374 __kasan_report.cold+0x1b/0x41 mm/kasan/report.c:506 kasan_report+0x12/0x20 mm/kasan/common.c:634 __asan_report_load8_noabort+0x14/0x20 mm/kasan/generic_report.c:132 finish_writeback_work.isra.0+0x11b/0x120 fs/fs-writeback.c:168 wb_do_writeback fs/fs-writeback.c:2030 [inline] wb_workfn+0x34f/0x1220 fs/fs-writeback.c:2070 process_one_work+0x9af/0x1740 kernel/workqueue.c:2269 worker_thread+0x98/0xe40 kernel/workqueue.c:2415 kthread+0x361/0x430 kernel/kthread.c:255 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352 The buggy address belongs to the page: page:ffffea0001bc13c0 refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 flags: 0x1fffc0000000000() raw: 01fffc0000000000 0000000000000000 ffffffff01bc0101 0000000000000000 raw: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff88806f04f880: 00 00 00 00 00 00 00 00 00 00 00 00 00 f1 f1 f1 ffff88806f04f900: f1 00 00 f3 f3 00 00 00 00 00 00 00 00 00 00 00 > ffff88806f04f980: 00 00 00 00 00 00 00 00 f1 f1 f1 f1 00 f3 f3 f3 ^ ffff88806f04fa00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 f1 ffff88806f04fa80: f1 f1 f1 00 f2 f2 f2 00 00 00 00 00 00 00 00 00 ================================================================== --- This bug 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 bug report. See: https://goo.gl/tpsmEJ#status for how to communicate with syzbot.