====================================================== WARNING: possible circular locking dependency detected 6.6.0-rc7-syzkaller #0 Not tainted ------------------------------------------------------ syz-executor.0/5420 is trying to acquire lock: ffff88801f15d0b8 (&hdev->req_lock){+.+.}-{3:3}, at: hci_dev_do_close net/bluetooth/hci_core.c:552 [inline] ffff88801f15d0b8 (&hdev->req_lock){+.+.}-{3:3}, at: hci_rfkill_set_block+0x12d/0x210 net/bluetooth/hci_core.c:956 but task is already holding lock: ffffffff8e78e448 (rfkill_global_mutex){+.+.}-{3:3}, at: rfkill_fop_write+0x1a9/0x790 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+0x136/0xd60 kernel/locking/mutex.c:747 rfkill_register+0x34/0x8c0 net/rfkill/core.c:1075 hci_register_dev+0x4e3/0xa40 net/bluetooth/hci_core.c:2656 __vhci_create_device drivers/bluetooth/hci_vhci.c:437 [inline] vhci_create_device+0x3ba/0x720 drivers/bluetooth/hci_vhci.c:478 vhci_get_user drivers/bluetooth/hci_vhci.c:535 [inline] vhci_write+0x3c7/0x480 drivers/bluetooth/hci_vhci.c:615 call_write_iter include/linux/fs.h:1956 [inline] new_sync_write fs/read_write.c:491 [inline] vfs_write+0x782/0xaf0 fs/read_write.c:584 ksys_write+0x1a0/0x2c0 fs/read_write.c:637 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x41/0x90 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd -> #2 (&data->open_mutex){+.+.}-{3:3}: __mutex_lock_common kernel/locking/mutex.c:603 [inline] __mutex_lock+0x136/0xd60 kernel/locking/mutex.c:747 vhci_send_frame+0x8e/0xf0 drivers/bluetooth/hci_vhci.c:78 hci_send_frame+0x1ef/0x370 net/bluetooth/hci_core.c:3039 hci_sched_acl_pkt net/bluetooth/hci_core.c:3651 [inline] hci_sched_acl net/bluetooth/hci_core.c:3736 [inline] hci_tx_work+0xed4/0x1ef0 net/bluetooth/hci_core.c:3835 process_one_work kernel/workqueue.c:2630 [inline] process_scheduled_works+0x90f/0x1400 kernel/workqueue.c:2703 worker_thread+0xa5f/0xff0 kernel/workqueue.c:2784 kthread+0x2d3/0x370 kernel/kthread.c:388 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:304 -> #1 ((work_completion)(&hdev->tx_work)){+.+.}-{0:0}: __flush_work+0x102/0xac0 kernel/workqueue.c:3403 hci_dev_close_sync+0x237/0xfe0 net/bluetooth/hci_sync.c:4982 hci_dev_do_close net/bluetooth/hci_core.c:554 [inline] hci_unregister_dev+0x1e3/0x4e0 net/bluetooth/hci_core.c:2737 vhci_release+0x83/0xd0 drivers/bluetooth/hci_vhci.c:672 __fput+0x3f8/0x910 fs/file_table.c:384 task_work_run+0x24a/0x300 kernel/task_work.c:180 exit_task_work include/linux/task_work.h:38 [inline] do_exit+0xa2c/0x2650 kernel/exit.c:874 do_group_exit+0x206/0x2c0 kernel/exit.c:1024 get_signal+0x175d/0x1840 kernel/signal.c:2892 arch_do_signal_or_restart+0x96/0x830 arch/x86/kernel/signal.c:309 exit_to_user_mode_loop+0x6a/0x100 kernel/entry/common.c:168 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:204 __syscall_exit_to_user_mode_work kernel/entry/common.c:285 [inline] syscall_exit_to_user_mode+0x64/0x280 kernel/entry/common.c:296 do_syscall_64+0x4d/0x90 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x63/0xcd -> #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+0x39ff/0x7f70 kernel/locking/lockdep.c:5136 lock_acquire+0x1e3/0x520 kernel/locking/lockdep.c:5753 __mutex_lock_common kernel/locking/mutex.c:603 [inline] __mutex_lock+0x136/0xd60 kernel/locking/mutex.c:747 hci_dev_do_close net/bluetooth/hci_core.c:552 [inline] hci_rfkill_set_block+0x12d/0x210 net/bluetooth/hci_core.c:956 rfkill_set_block+0x1e7/0x430 net/rfkill/core.c:346 rfkill_fop_write+0x5bb/0x790 net/rfkill/core.c:1305 vfs_write+0x286/0xaf0 fs/read_write.c:582 ksys_write+0x1a0/0x2c0 fs/read_write.c:637 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x41/0x90 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd 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.0/5420: #0: ffffffff8e78e448 (rfkill_global_mutex){+.+.}-{3:3}, at: rfkill_fop_write+0x1a9/0x790 net/rfkill/core.c:1297 stack backtrace: CPU: 0 PID: 5420 Comm: syz-executor.0 Not tainted 6.6.0-rc7-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/06/2023 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e7/0x2d0 lib/dump_stack.c:106 check_noncircular+0x375/0x4a0 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+0x39ff/0x7f70 kernel/locking/lockdep.c:5136 lock_acquire+0x1e3/0x520 kernel/locking/lockdep.c:5753 __mutex_lock_common kernel/locking/mutex.c:603 [inline] __mutex_lock+0x136/0xd60 kernel/locking/mutex.c:747 hci_dev_do_close net/bluetooth/hci_core.c:552 [inline] hci_rfkill_set_block+0x12d/0x210 net/bluetooth/hci_core.c:956 rfkill_set_block+0x1e7/0x430 net/rfkill/core.c:346 rfkill_fop_write+0x5bb/0x790 net/rfkill/core.c:1305 vfs_write+0x286/0xaf0 fs/read_write.c:582 ksys_write+0x1a0/0x2c0 fs/read_write.c:637 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x41/0x90 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7fc9e7a7cae9 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:00007fc9e87e20c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007fc9e7b9bf80 RCX: 00007fc9e7a7cae9 RDX: 0000000000000008 RSI: 0000000020000080 RDI: 0000000000000003 RBP: 00007fc9e7ac847a R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000000b R14: 00007fc9e7b9bf80 R15: 00007fffa23a4ca8