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 56D87ECE58E for ; Mon, 14 Oct 2019 02:49:17 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 3A7B52067B for ; Mon, 14 Oct 2019 02:49:17 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729843AbfJNCtL (ORCPT ); Sun, 13 Oct 2019 22:49:11 -0400 Received: from mail-io1-f70.google.com ([209.85.166.70]:46422 "EHLO mail-io1-f70.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729776AbfJNCtK (ORCPT ); Sun, 13 Oct 2019 22:49:10 -0400 Received: by mail-io1-f70.google.com with SMTP id t11so24616477ioc.13 for ; Sun, 13 Oct 2019 19:49:08 -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=9V4klit+hozv+mbRrTrN0UpLT9Ett4RqcQ2DA9o6Nvo=; b=SiC6/TFcOC4e5J5sfclxH/KGzSngf5jD20Mkx33wHDDvPdD6rhEPtojLh8Drc8iOlH xBY5iRp/X55D2nLoaP++fj6cnRnl+zFvYBwSu3sfveKOXlo0Bac2wFAB4syi/49zxa0x 7JqMsFiCQdXtmiJtJBngeNYf1qha4xE+D8/nBg08jpLbg58S0EXamt63UVTqa9mwNK3L r2fz+uFYnkQ3z+U6lODpfMKjpx4397LjNNJjqWi1/GazHj8Jv/OGo3TuRL1ZI6F9FWDa yhCl63ecbl8GslhhfvniuMOavF0f8wRkhiTbXDGPswe7EDvqEpWcYrdZWeGk2o82JLHB vFpA== X-Gm-Message-State: APjAAAWEdwF6hKQXN5/do7X1CjSnUOOkDH+o9ef5DkgCdfRRX0ULNA19 2RvS1fKljec9gC0X439p9rznIOnj11FaW6DUhi0qOk6tNvhu X-Google-Smtp-Source: APXvYqz5uT/zj8pn24FxdfXVgsaToFpZju09zN4x5T7bBvOevF5cYViVd4CO+zGOaNNnkRSmA46DEeA2usVGaNUrbQMHcrFcwMcf MIME-Version: 1.0 X-Received: by 2002:a5e:d718:: with SMTP id v24mr14423069iom.24.1571021348408; Sun, 13 Oct 2019 19:49:08 -0700 (PDT) Date: Sun, 13 Oct 2019 19:49:08 -0700 X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <0000000000006819150594d5e956@google.com> Subject: WARNING: refcount bug in sock_wfree (2) From: syzbot To: axboe@kernel.dk, davem@davemloft.net, hare@suse.com, jmoyer@redhat.com, linux-block@vger.kernel.org, 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: 442630f6 Add linux-next specific files for 20191008 git tree: linux-next console output: https://syzkaller.appspot.com/x/log.txt?x=158fa6bf600000 kernel config: https://syzkaller.appspot.com/x/.config?x=af1bfeef713eefdd dashboard link: https://syzkaller.appspot.com/bug?extid=c0ba5b9e742f049a2edf compiler: gcc (GCC) 9.0.0 20181231 (experimental) syz repro: https://syzkaller.appspot.com/x/repro.syz?x=15a861b3600000 C reproducer: https://syzkaller.appspot.com/x/repro.c?x=1769f48b600000 The bug was bisected to: commit 6c080ff07363389cb4092193eb333639f0392b8c Author: Jens Axboe Date: Thu Oct 3 14:11:03 2019 +0000 io_uring: allow sparse fixed file sets bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=1344b993600000 final crash: https://syzkaller.appspot.com/x/report.txt?x=10c4b993600000 console output: https://syzkaller.appspot.com/x/log.txt?x=1744b993600000 IMPORTANT: if you fix the bug, please add the following tag to the commit: Reported-by: syzbot+c0ba5b9e742f049a2edf@syzkaller.appspotmail.com Fixes: 6c080ff07363 ("io_uring: allow sparse fixed file sets") ------------[ cut here ]------------ refcount_t: underflow; use-after-free. WARNING: CPU: 0 PID: 8691 at lib/refcount.c:190 refcount_sub_and_test_checked lib/refcount.c:190 [inline] WARNING: CPU: 0 PID: 8691 at lib/refcount.c:190 refcount_sub_and_test_checked+0x1d0/0x200 lib/refcount.c:180 Kernel panic - not syncing: panic_on_warn set ... CPU: 0 PID: 8691 Comm: syz-executor322 Not tainted 5.4.0-rc2-next-20191008 #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 panic+0x2e3/0x75c kernel/panic.c:221 __warn.cold+0x2f/0x35 kernel/panic.c:582 report_bug+0x289/0x300 lib/bug.c:195 fixup_bug arch/x86/kernel/traps.c:174 [inline] fixup_bug arch/x86/kernel/traps.c:169 [inline] do_error_trap+0x11b/0x200 arch/x86/kernel/traps.c:267 do_invalid_op+0x37/0x50 arch/x86/kernel/traps.c:286 invalid_op+0x23/0x30 arch/x86/entry/entry_64.S:1028 RIP: 0010:refcount_sub_and_test_checked lib/refcount.c:190 [inline] RIP: 0010:refcount_sub_and_test_checked+0x1d0/0x200 lib/refcount.c:180 Code: 1d b0 f0 7f 06 31 ff 89 de e8 6c d7 30 fe 84 db 75 94 e8 23 d6 30 fe 48 c7 c7 20 81 e6 87 c6 05 90 f0 7f 06 01 e8 e8 15 02 fe <0f> 0b e9 75 ff ff ff e8 04 d6 30 fe e9 6e ff ff ff 48 89 df e8 e7 RSP: 0018:ffff8880a8267a28 EFLAGS: 00010282 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000 RDX: 0000000000000000 RSI: ffffffff815cb676 RDI: ffffed101504cf37 RBP: ffff8880a8267ac0 R08: ffff888090e363c0 R09: fffffbfff14eeb42 R10: fffffbfff14eeb41 R11: ffffffff8a775a0f R12: 00000000fffffd02 R13: 0000000000000001 R14: ffff8880a8267a98 R15: 0000000000000001 sock_wfree+0x10c/0x190 net/core/sock.c:1958 unix_destruct_scm+0x115/0x170 net/unix/scm.c:149 io_destruct_skb+0x62/0x80 fs/io_uring.c:2995 skb_release_head_state+0xeb/0x260 net/core/skbuff.c:652 skb_release_all+0x16/0x60 net/core/skbuff.c:663 __kfree_skb net/core/skbuff.c:679 [inline] kfree_skb net/core/skbuff.c:697 [inline] kfree_skb+0x101/0x3c0 net/core/skbuff.c:691 __io_sqe_files_scm+0x429/0x640 fs/io_uring.c:3049 io_sqe_files_scm fs/io_uring.c:3071 [inline] io_sqe_files_register fs/io_uring.c:3154 [inline] __io_uring_register+0x1f69/0x2d70 fs/io_uring.c:4152 __do_sys_io_uring_register fs/io_uring.c:4204 [inline] __se_sys_io_uring_register fs/io_uring.c:4186 [inline] __x64_sys_io_uring_register+0x193/0x1f0 fs/io_uring.c:4186 do_syscall_64+0xfa/0x760 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x440279 Code: 18 89 d0 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 fb 13 fc ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007ffeeedc31e8 EFLAGS: 00000246 ORIG_RAX: 00000000000001ab RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 0000000000440279 RDX: 0000000020000280 RSI: 0000000000000002 RDI: 0000000000000003 RBP: 00000000006ca018 R08: 0000000000000000 R09: 00000000004002c8 R10: 0000000000000001 R11: 0000000000000246 R12: 0000000000401b00 R13: 0000000000401b90 R14: 0000000000000000 R15: 0000000000000000 Kernel Offset: disabled Rebooting in 86400 seconds.. --- 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. For information about bisection process see: https://goo.gl/tpsmEJ#bisection syzbot can test patches for this bug, for details see: https://goo.gl/tpsmEJ#testing-patches