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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id A035FC07548 for ; Wed, 15 Nov 2023 07:59:09 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1343498AbjKOH7K (ORCPT ); Wed, 15 Nov 2023 02:59:10 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:60380 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229551AbjKOH7I (ORCPT ); Wed, 15 Nov 2023 02:59:08 -0500 Received: from mail-pg1-f198.google.com (mail-pg1-f198.google.com [209.85.215.198]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 20C7DDF for ; Tue, 14 Nov 2023 23:59:05 -0800 (PST) Received: by mail-pg1-f198.google.com with SMTP id 41be03b00d2f7-5bddc607b45so7721625a12.0 for ; Tue, 14 Nov 2023 23:59:05 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1700035144; x=1700639944; h=to:from:subject:message-id:in-reply-to:date:mime-version :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=mDt55pcQcJTCKnDvEunhcbszJ+01mPEhMMwDOq3G3qw=; b=iB/zT+dZqrRhFsTN4YGVvRXdlTL2tSuwvUiFGOVpx/+zelNt5jJSpCdQHftRwopHaz CSXHaJKhKouzbwdkAhfmYiN8/AUiYyMwmyEUoLsqM2z77Ey8TrNfdq7LUoXdLmboqoxC 4kS7jA5cQg83frHYwnidm/BlhEEWnpExww4WJ8+M0T7jokwRRboBqJw0LnInIkcYWvwK RbH5FoE43zkGe9EajF5lg8/Z8Iklpkvtzr9VbCSmL0BwJtCiNnHwHbCPBcpBvZe/6EuR nLDkKv/q44/z/SkSGlo3DcOdVJLkk6Lm35jgoe3N9zF9HgpjXTESKsm4RJuD+LQVBXqv TdjQ== X-Gm-Message-State: AOJu0YwGVHxVrRq28OEDy4jOxpxmIyvkvlWhw1SUQn8c/1p7mORU5qEh 0x47HrBKdXo6ieDkat8hMvGeiYQ8H6ea4rmSPWV/8cYyzSQJcEI= X-Google-Smtp-Source: AGHT+IEMrB6+yZt81RAhAFWHEhi6iOVJg6NLekuwqW8Mcpvj3Dw9X+9Y/ce4TdXXsq6zOoHphD6k4/HNqdA0rih7Ie9na0BVVmpX MIME-Version: 1.0 X-Received: by 2002:a05:6a02:493:b0:5bd:d7de:a5f with SMTP id bw19-20020a056a02049300b005bdd7de0a5fmr1466182pgb.0.1700035144658; Tue, 14 Nov 2023 23:59:04 -0800 (PST) Date: Tue, 14 Nov 2023 23:59:04 -0800 In-Reply-To: X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <000000000000e73823060a2c466c@google.com> Subject: Re: [syzbot] [bluetooth?] possible deadlock in hci_dev_do_close From: syzbot To: linux-kernel@vger.kernel.org, mukattreyee@gmail.com, syzkaller-bugs@googlegroups.com Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hello, syzbot has tested the proposed patch but the reproducer is still triggering an issue: possible deadlock in hci_dev_do_close ====================================================== WARNING: possible circular locking dependency detected 6.7.0-rc1-syzkaller-00019-gc42d9eeef8e5 #0 Not tainted ------------------------------------------------------ syz-executor.0/5493 is trying to acquire lock: ffff88801ccf1108 (&hdev->req_lock){+.+.}-{3:3}, at: hci_dev_do_close+0x26/0x90 net/bluetooth/hci_core.c:552 but task is already holding lock: ffffffff8ef37888 (rfkill_global_mutex){+.+.}-{3:3}, at: rfkill_fop_write+0x16e/0x570 net/rfkill/core.c:1297 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #3 (rfkill_global_mutex){+.+.}-{3:3}: __mutex_lock_common kernel/locking/mutex.c:603 [inline] __mutex_lock+0x181/0x1340 kernel/locking/mutex.c:747 rfkill_register+0x3a/0xb30 net/rfkill/core.c:1075 hci_register_dev+0x43a/0xd40 net/bluetooth/hci_core.c:2658 __vhci_create_device+0x393/0x800 drivers/bluetooth/hci_vhci.c:437 vhci_create_device drivers/bluetooth/hci_vhci.c:478 [inline] vhci_get_user drivers/bluetooth/hci_vhci.c:535 [inline] vhci_write+0x2c7/0x470 drivers/bluetooth/hci_vhci.c:615 call_write_iter include/linux/fs.h:2020 [inline] new_sync_write fs/read_write.c:491 [inline] vfs_write+0x64f/0xdf0 fs/read_write.c:584 ksys_write+0x12f/0x250 fs/read_write.c:637 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x3f/0x110 arch/x86/entry/common.c:82 entry_SYSCALL_64_after_hwframe+0x63/0x6b -> #2 (&data->open_mutex){+.+.}-{3:3}: __mutex_lock_common kernel/locking/mutex.c:603 [inline] __mutex_lock+0x181/0x1340 kernel/locking/mutex.c:747 vhci_send_frame+0x67/0xa0 drivers/bluetooth/hci_vhci.c:78 hci_send_frame+0x220/0x470 net/bluetooth/hci_core.c:3042 hci_sched_acl_pkt net/bluetooth/hci_core.c:3654 [inline] hci_sched_acl net/bluetooth/hci_core.c:3739 [inline] hci_tx_work+0x1456/0x1e40 net/bluetooth/hci_core.c:3838 process_one_work+0x884/0x15c0 kernel/workqueue.c:2630 process_scheduled_works kernel/workqueue.c:2703 [inline] worker_thread+0x8b9/0x1290 kernel/workqueue.c:2784 kthread+0x33c/0x440 kernel/kthread.c:388 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:242 -> #1 ((work_completion)(&hdev->tx_work)){+.+.}-{0:0}: __flush_work+0x103/0xa10 kernel/workqueue.c:3403 hci_dev_close_sync+0x22d/0x1160 net/bluetooth/hci_sync.c:4982 hci_dev_do_close+0x2e/0x90 net/bluetooth/hci_core.c:554 hci_unregister_dev+0x1eb/0x600 net/bluetooth/hci_core.c:2739 vhci_release+0x7f/0x100 drivers/bluetooth/hci_vhci.c:672 __fput+0x270/0xbb0 fs/file_table.c:394 task_work_run+0x14d/0x240 kernel/task_work.c:180 exit_task_work include/linux/task_work.h:38 [inline] do_exit+0xa92/0x2ae0 kernel/exit.c:871 do_group_exit+0xd4/0x2a0 kernel/exit.c:1021 get_signal+0x23ba/0x2790 kernel/signal.c:2904 arch_do_signal_or_restart+0x90/0x7f0 arch/x86/kernel/signal.c:309 exit_to_user_mode_loop kernel/entry/common.c:168 [inline] exit_to_user_mode_prepare+0x11f/0x240 kernel/entry/common.c:204 __syscall_exit_to_user_mode_work kernel/entry/common.c:285 [inline] syscall_exit_to_user_mode+0x1d/0x60 kernel/entry/common.c:296 do_syscall_64+0x4b/0x110 arch/x86/entry/common.c:88 entry_SYSCALL_64_after_hwframe+0x63/0x6b -> #0 (&hdev->req_lock){+.+.}-{3:3}: check_prev_add kernel/locking/lockdep.c:3134 [inline] check_prevs_add kernel/locking/lockdep.c:3253 [inline] validate_chain kernel/locking/lockdep.c:3868 [inline] __lock_acquire+0x2e3d/0x5de0 kernel/locking/lockdep.c:5136 lock_acquire kernel/locking/lockdep.c:5753 [inline] lock_acquire+0x1ae/0x510 kernel/locking/lockdep.c:5718 __mutex_lock_common kernel/locking/mutex.c:603 [inline] __mutex_lock+0x181/0x1340 kernel/locking/mutex.c:747 hci_dev_do_close+0x26/0x90 net/bluetooth/hci_core.c:552 hci_rfkill_set_block+0x1b9/0x200 net/bluetooth/hci_core.c:956 rfkill_set_block+0x200/0x550 net/rfkill/core.c:346 rfkill_fop_write+0x2d4/0x570 net/rfkill/core.c:1305 vfs_write+0x2a4/0xdf0 fs/read_write.c:582 ksys_write+0x1f0/0x250 fs/read_write.c:637 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x3f/0x110 arch/x86/entry/common.c:82 entry_SYSCALL_64_after_hwframe+0x63/0x6b other info that might help us debug this: Chain exists of: &hdev->req_lock --> &data->open_mutex --> rfkill_global_mutex Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(rfkill_global_mutex); lock(&data->open_mutex); lock(rfkill_global_mutex); lock(&hdev->req_lock); *** DEADLOCK *** 1 lock held by syz-executor.0/5493: #0: ffffffff8ef37888 (rfkill_global_mutex){+.+.}-{3:3}, at: rfkill_fop_write+0x16e/0x570 net/rfkill/core.c:1297 stack backtrace: CPU: 0 PID: 5493 Comm: syz-executor.0 Not tainted 6.7.0-rc1-syzkaller-00019-gc42d9eeef8e5 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/10/2023 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xd9/0x1b0 lib/dump_stack.c:106 check_noncircular+0x311/0x3f0 kernel/locking/lockdep.c:2187 check_prev_add kernel/locking/lockdep.c:3134 [inline] check_prevs_add kernel/locking/lockdep.c:3253 [inline] validate_chain kernel/locking/lockdep.c:3868 [inline] __lock_acquire+0x2e3d/0x5de0 kernel/locking/lockdep.c:5136 lock_acquire kernel/locking/lockdep.c:5753 [inline] lock_acquire+0x1ae/0x510 kernel/locking/lockdep.c:5718 __mutex_lock_common kernel/locking/mutex.c:603 [inline] __mutex_lock+0x181/0x1340 kernel/locking/mutex.c:747 hci_dev_do_close+0x26/0x90 net/bluetooth/hci_core.c:552 hci_rfkill_set_block+0x1b9/0x200 net/bluetooth/hci_core.c:956 rfkill_set_block+0x200/0x550 net/rfkill/core.c:346 rfkill_fop_write+0x2d4/0x570 net/rfkill/core.c:1305 vfs_write+0x2a4/0xdf0 fs/read_write.c:582 ksys_write+0x1f0/0x250 fs/read_write.c:637 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x3f/0x110 arch/x86/entry/common.c:82 entry_SYSCALL_64_after_hwframe+0x63/0x6b RIP: 0033:0x7f3f7767cae9 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 00 00 90 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 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f3f784bb0c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007f3f7779bf80 RCX: 00007f3f7767cae9 RDX: 0000000000000008 RSI: 0000000020000080 RDI: 0000000000000003 RBP: 00007f3f776c847a R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000000b R14: 00007f3f7779bf80 R15: 00007ffcc7902e88 Tested on: commit: c42d9eee Merge tag 'hardening-v6.7-rc2' of git://git.k.. git tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master console output: https://syzkaller.appspot.com/x/log.txt?x=131e8198e80000 kernel config: https://syzkaller.appspot.com/x/.config?x=c8be8f62c2cfe457 dashboard link: https://syzkaller.appspot.com/bug?extid=4e3a76c5c505a3f49083 compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40 Note: no patches were applied.