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 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 E965FCA9EB9 for ; Sun, 27 Oct 2019 02:36:10 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id C1B062084C for ; Sun, 27 Oct 2019 02:36:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726605AbfJ0CgK (ORCPT ); Sat, 26 Oct 2019 22:36:10 -0400 Received: from mail-io1-f72.google.com ([209.85.166.72]:43122 "EHLO mail-io1-f72.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726592AbfJ0CgK (ORCPT ); Sat, 26 Oct 2019 22:36:10 -0400 Received: by mail-io1-f72.google.com with SMTP id i2so5394028ioo.10 for ; Sat, 26 Oct 2019 19:36:09 -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:in-reply-to:message-id:subject :from:to; bh=yCx8cEP9LpJ4m50eMQ5ykCVi6OurwW26hlxrBSgzIkc=; b=dfbJmUUm6ztstPz08ceN38lQ/tzlD5xi4cvxGylXYE4GyZLn4VWw2DBdVcIi7Qe0/P 0sax1k0P4j2nrQWgBovT/nrGZKlOSp/fwEty49JYdgP465ijopdkPe4db3kRKJIwDSNU Dj/97D/0OJ/xOX8t7q/ihigYMpV18N17OWZsYxmq7YcAxMFFy5efDt0SOEVkHNGgEDu6 ar8RHm38txo3YblNN49raMTitxGJMlxSdIww11SIxbnLZC7u9e40z5TDl/ZN2nTOGVqd ESSM9A/MooQVWhrqdmv/rXw6VHV7tG11Fm5fRlMiY/MTGWeuiP6A57LRxDr+xjTNP3RV GIyA== X-Gm-Message-State: APjAAAXP6XEbrOQ4huB4IQYA0xl2oHypMMPVqwYcGXiu4l/AiOzWD3w4 ODGUtlsvjm3CAJmb/WAbf9ie619n6INyg3ejTrK23RTzXby4 X-Google-Smtp-Source: APXvYqwgZBh1WoBbz1CdFayyooQPEDzAySNCiRpQRVGPlm1srTgOFJl4hk7hmSSXBUduywkG70WG6ZWJwZ7LvqdCNKQ5C5bBEPX0 MIME-Version: 1.0 X-Received: by 2002:a5d:814c:: with SMTP id f12mr12008236ioo.174.1572143769334; Sat, 26 Oct 2019 19:36:09 -0700 (PDT) Date: Sat, 26 Oct 2019 19:36:09 -0700 In-Reply-To: <000000000000fbbe1e0595bac322@google.com> X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <000000000000e83aa20595db3e33@google.com> Subject: Re: KASAN: null-ptr-deref Write in io_wq_cancel_all From: syzbot To: axboe@kernel.dk, dvyukov@google.com, linux-fsdevel@vger.kernel.org, linux-kernel@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 syzbot has found a reproducer for the following crash on: HEAD commit: 139c2d13 Add linux-next specific files for 20191025 git tree: linux-next console output: https://syzkaller.appspot.com/x/log.txt?x=12888a00e00000 kernel config: https://syzkaller.appspot.com/x/.config?x=28fd7a693df38d29 dashboard link: https://syzkaller.appspot.com/bug?extid=d958a65633ea70280b23 compiler: gcc (GCC) 9.0.0 20181231 (experimental) syz repro: https://syzkaller.appspot.com/x/repro.syz?x=160573c0e00000 IMPORTANT: if you fix the bug, please add the following tag to the commit: Reported-by: syzbot+d958a65633ea70280b23@syzkaller.appspotmail.com ================================================================== BUG: KASAN: null-ptr-deref in set_bit include/asm-generic/bitops-instrumented.h:28 [inline] BUG: KASAN: null-ptr-deref in io_wq_cancel_all+0x28/0x2a0 fs/io-wq.c:574 Write of size 8 at addr 0000000000000004 by task syz-executor.2/9365 CPU: 1 PID: 9365 Comm: syz-executor.2 Not tainted 5.4.0-rc4-next-20191025 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x172/0x1f0 lib/dump_stack.c:113 __kasan_report.cold+0x5/0x41 mm/kasan/report.c:510 kasan_report+0x12/0x20 mm/kasan/common.c:634 check_memory_region_inline mm/kasan/generic.c:185 [inline] check_memory_region+0x134/0x1a0 mm/kasan/generic.c:192 __kasan_check_write+0x14/0x20 mm/kasan/common.c:98 set_bit include/asm-generic/bitops-instrumented.h:28 [inline] io_wq_cancel_all+0x28/0x2a0 fs/io-wq.c:574 io_ring_ctx_wait_and_kill+0x1e2/0x710 fs/io_uring.c:3679 io_uring_release+0x42/0x50 fs/io_uring.c:3691 __fput+0x2ff/0x890 fs/file_table.c:280 ____fput+0x16/0x20 fs/file_table.c:313 task_work_run+0x145/0x1c0 kernel/task_work.c:113 exit_task_work include/linux/task_work.h:22 [inline] do_exit+0x904/0x2e60 kernel/exit.c:817 do_group_exit+0x135/0x360 kernel/exit.c:921 get_signal+0x47c/0x24f0 kernel/signal.c:2734 do_signal+0x87/0x1700 arch/x86/kernel/signal.c:815 exit_to_usermode_loop+0x286/0x380 arch/x86/entry/common.c:159 prepare_exit_to_usermode arch/x86/entry/common.c:194 [inline] syscall_return_slowpath+0x47a/0x530 arch/x86/entry/common.c:274 ret_from_fork+0x15/0x30 arch/x86/entry/entry_64.S:344 RIP: 0033:0x45c909 Code: ff 48 85 f6 0f 84 d7 8c fb ff 48 83 ee 10 48 89 4e 08 48 89 3e 48 89 d7 4c 89 c2 4d 89 c8 4c 8b 54 24 08 b8 38 00 00 00 0f 05 <48> 85 c0 0f 8c ae 8c fb ff 74 01 c3 31 ed 48 f7 c7 00 00 01 00 75 RSP: 002b:00007fe3de137db0 EFLAGS: 00000202 ORIG_RAX: 0000000000000038 RAX: 0000000000000000 RBX: 00007fe3de138700 RCX: 000000000045c909 RDX: 00007fe3de1389d0 RSI: 00007fe3de137db0 RDI: 00000000003d0f00 RBP: 00007ffff688f6a0 R08: 00007fe3de138700 R09: 00007fe3de138700 R10: 00007fe3de1389d0 R11: 0000000000000202 R12: 0000000000000000 R13: 00007ffff688f53f R14: 00007fe3de1389c0 R15: 000000000075bfd4 ==================================================================