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=-4.0 required=3.0 tests=BAYES_00,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 64496C433E3 for ; Thu, 13 Aug 2020 05:24:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4CCB5207DA for ; Thu, 13 Aug 2020 05:24:23 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726253AbgHMFYV (ORCPT ); Thu, 13 Aug 2020 01:24:21 -0400 Received: from mail-io1-f69.google.com ([209.85.166.69]:33277 "EHLO mail-io1-f69.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725982AbgHMFYU (ORCPT ); Thu, 13 Aug 2020 01:24:20 -0400 Received: by mail-io1-f69.google.com with SMTP id a12so3310814ioo.0 for ; Wed, 12 Aug 2020 22:24:19 -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=MIGAdD8AV/NC1BP8vlLnD+v3sHhkKr3057HeKchSrxM=; b=gCJR0Fe98nZ5Spmi16FcMs67nNyeUj4EfAq1KT6P6eliHLrZOqSDuJeZAzqz0Rfye+ dU7237PyhUEN9+wRBXdQ3AQ/Fmo1gXrS9/JCW8HU1fOh71zTYPBOddjm2ZZSFaNNoXVh jUsGxdHtbt9Wx6X6qJiy9g1H42hd0YXQJf67phuJmReFv+IPQs5UP6C2WEqE3UO5YKD6 LnUKw5lZlQWqi5VrJ+72oK5jGkPVQvKOR9AmV4gTJBq/VH88IJNroEkabXfaqJeqcfoS yeOSW2mctrwQjrFRw+9JOhpog8Ro9mEYPAgE808Xs+mMbRkXWrLyxe/sTgjt7bfABFDx 1JGw== X-Gm-Message-State: AOAM530m7/CgMZ4sZbGLw+FV5bYQbk7f/oSHC7wBE2A71xEgAdKW/BX2 nYXMC9jJXCAtdtjBCSi32k9jUMXcdf0PtOS4270X9VWLJydf X-Google-Smtp-Source: ABdhPJxe/Y534Kujvl7uJwA40M2Jd7ICtQOtb+65Yk6LhxvJf9iNcev7hCxUSV5nArY+7yR3D+MdMzCJp8K5VbfJa70QRQfGBks0 MIME-Version: 1.0 X-Received: by 2002:a92:d9d1:: with SMTP id n17mr2940649ilq.182.1597296259060; Wed, 12 Aug 2020 22:24:19 -0700 (PDT) Date: Wed, 12 Aug 2020 22:24:19 -0700 In-Reply-To: <00000000000042af6205ac444172@google.com> X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <0000000000001f5a1105acbb8483@google.com> Subject: Re: WARNING: locking bug in l2cap_chan_del From: syzbot To: davem@davemloft.net, johan.hedberg@gmail.com, kuba@kernel.org, linux-bluetooth@vger.kernel.org, linux-kernel@vger.kernel.org, marcel@holtmann.org, netdev@vger.kernel.org, syzkaller-bugs@googlegroups.com Content-Type: text/plain; charset="UTF-8" Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org syzbot has found a reproducer for the following issue on: HEAD commit: 06a7a37b ipv4: tunnel: fix compilation on ARCH=um git tree: net console output: https://syzkaller.appspot.com/x/log.txt?x=115caa16900000 kernel config: https://syzkaller.appspot.com/x/.config?x=7bb894f55faf8242 dashboard link: https://syzkaller.appspot.com/bug?extid=01d7fc00b2a0419d01cc compiler: gcc (GCC) 10.1.0-syz 20200507 syz repro: https://syzkaller.appspot.com/x/repro.syz?x=13fb564a900000 IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+01d7fc00b2a0419d01cc@syzkaller.appspotmail.com ------------[ cut here ]------------ DEBUG_LOCKS_WARN_ON(1) WARNING: CPU: 0 PID: 5 at kernel/locking/lockdep.c:183 hlock_class kernel/locking/lockdep.c:183 [inline] WARNING: CPU: 0 PID: 5 at kernel/locking/lockdep.c:183 hlock_class kernel/locking/lockdep.c:172 [inline] WARNING: CPU: 0 PID: 5 at kernel/locking/lockdep.c:183 check_wait_context kernel/locking/lockdep.c:4100 [inline] WARNING: CPU: 0 PID: 5 at kernel/locking/lockdep.c:183 __lock_acquire+0x1674/0x5640 kernel/locking/lockdep.c:4376 Kernel panic - not syncing: panic_on_warn set ... CPU: 0 PID: 5 Comm: kworker/0:0 Not tainted 5.8.0-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: events l2cap_chan_timeout Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x18f/0x20d lib/dump_stack.c:118 panic+0x2e3/0x75c kernel/panic.c:231 __warn.cold+0x20/0x45 kernel/panic.c:600 report_bug+0x1bd/0x210 lib/bug.c:198 handle_bug+0x38/0x90 arch/x86/kernel/traps.c:235 exc_invalid_op+0x14/0x40 arch/x86/kernel/traps.c:255 asm_exc_invalid_op+0x12/0x20 arch/x86/include/asm/idtentry.h:536 RIP: 0010:hlock_class kernel/locking/lockdep.c:183 [inline] RIP: 0010:hlock_class kernel/locking/lockdep.c:172 [inline] RIP: 0010:check_wait_context kernel/locking/lockdep.c:4100 [inline] RIP: 0010:__lock_acquire+0x1674/0x5640 kernel/locking/lockdep.c:4376 Code: d2 0f 85 f1 36 00 00 44 8b 15 f0 8e 57 09 45 85 d2 0f 85 1c fa ff ff 48 c7 c6 80 af 4b 88 48 c7 c7 80 aa 4b 88 e8 ce 36 eb ff <0f> 0b e9 02 fa ff ff c7 44 24 38 fe ff ff ff 41 bf 01 00 00 00 c7 RSP: 0018:ffffc90000cbf8e0 EFLAGS: 00010086 RAX: 0000000000000000 RBX: 0000000000000004 RCX: 0000000000000000 RDX: ffff8880a95a2140 RSI: ffffffff815d8eb7 RDI: fffff52000197f0e RBP: ffff8880a95a2ab0 R08: 0000000000000000 R09: ffffffff89bcb3c3 R10: 00000000000007d2 R11: 0000000000000001 R12: 0000000000000000 R13: 00000000000019a1 R14: ffff8880a95a2140 R15: 0000000000040000 lock_acquire+0x1f1/0xad0 kernel/locking/lockdep.c:5005 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:135 [inline] _raw_spin_lock_bh+0x2f/0x40 kernel/locking/spinlock.c:175 spin_lock_bh include/linux/spinlock.h:359 [inline] lock_sock_nested+0x3b/0x110 net/core/sock.c:3040 l2cap_sock_teardown_cb+0x88/0x400 net/bluetooth/l2cap_sock.c:1520 l2cap_chan_del+0xad/0x1300 net/bluetooth/l2cap_core.c:618 l2cap_chan_close+0x118/0xb10 net/bluetooth/l2cap_core.c:823 l2cap_chan_timeout+0x173/0x450 net/bluetooth/l2cap_core.c:436 process_one_work+0x94c/0x1670 kernel/workqueue.c:2269 worker_thread+0x64c/0x1120 kernel/workqueue.c:2415 kthread+0x3b5/0x4a0 kernel/kthread.c:292 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294 Kernel Offset: disabled Rebooting in 86400 seconds..