======================================================
WARNING: possible circular locking dependency detected
5.10.205 #1 Not tainted
------------------------------------------------------
syz-executor.2/9979 is trying to acquire lock:
ffff88800edf4b78 ((work_completion)(&hdev->bg_scan_update)){+.+.}-{0:0}, at: __flush_work+0xdd/0xa90 kernel/workqueue.c:3050

but task is already holding lock:
ffffffff85619628 (rfkill_global_mutex){+.+.}-{3:3}, at: rfkill_fop_write+0xff/0x4b0 net/rfkill/core.c:1232

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #5 (rfkill_global_mutex){+.+.}-{3:3}:
       __mutex_lock_common kernel/locking/mutex.c:968 [inline]
       __mutex_lock+0x13d/0x10b0 kernel/locking/mutex.c:1109
       rfkill_register+0x36/0xa10 net/rfkill/core.c:1016
       hci_register_dev+0x42e/0xc00 net/bluetooth/hci_core.c:3773
       __vhci_create_device+0x2c8/0x5c0 drivers/bluetooth/hci_vhci.c:129
       vhci_create_device drivers/bluetooth/hci_vhci.c:153 [inline]
       vhci_open_timeout+0x38/0x50 drivers/bluetooth/hci_vhci.c:310
       process_one_work+0x9a9/0x14b0 kernel/workqueue.c:2282
       worker_thread+0x61d/0x1310 kernel/workqueue.c:2428
       kthread+0x38f/0x470 kernel/kthread.c:313
       ret_from_fork+0x22/0x30 arch/x86/entry/entry_64.S:299

-> #4 (&data->open_mutex){+.+.}-{3:3}:
       __mutex_lock_common kernel/locking/mutex.c:968 [inline]
       __mutex_lock+0x13d/0x10b0 kernel/locking/mutex.c:1109
       vhci_send_frame+0x63/0xa0 drivers/bluetooth/hci_vhci.c:71
       hci_send_frame+0x1b9/0x320 net/bluetooth/hci_core.c:4060
       hci_cmd_work+0x15e/0x2d0 net/bluetooth/hci_core.c:5005
       process_one_work+0x9a9/0x14b0 kernel/workqueue.c:2282
       worker_thread+0x61d/0x1310 kernel/workqueue.c:2428
       kthread+0x38f/0x470 kernel/kthread.c:313
       ret_from_fork+0x22/0x30 arch/x86/entry/entry_64.S:299

-> #3 ((work_completion)(&hdev->cmd_work)){+.+.}-{0:0}:
       process_one_work+0x92d/0x14b0 kernel/workqueue.c:2258
       worker_thread+0x61d/0x1310 kernel/workqueue.c:2428
       kthread+0x38f/0x470 kernel/kthread.c:313
       ret_from_fork+0x22/0x30 arch/x86/entry/entry_64.S:299

-> #2 ((wq_completion)hci0#2){+.+.}-{0:0}:
       flush_workqueue+0x105/0x1140 kernel/workqueue.c:2793
       drain_workqueue+0x1a5/0x3c0 kernel/workqueue.c:2958
       hci_dev_do_reset net/bluetooth/hci_core.c:1887 [inline]
       hci_dev_reset+0x255/0x6b0 net/bluetooth/hci_core.c:1930
       hci_sock_ioctl+0x3b2/0x980 net/bluetooth/hci_sock.c:1072
       sock_do_ioctl+0xd3/0x300 net/socket.c:1064
       sock_ioctl+0x3ea/0x700 net/socket.c:1204
       vfs_ioctl fs/ioctl.c:48 [inline]
       __do_sys_ioctl fs/ioctl.c:753 [inline]
       __se_sys_ioctl fs/ioctl.c:739 [inline]
       __x64_sys_ioctl+0x19a/0x210 fs/ioctl.c:739
       do_syscall_64+0x33/0x40 arch/x86/entry/common.c:46
       entry_SYSCALL_64_after_hwframe+0x62/0xc7

-> #1 (&hdev->req_lock){+.+.}-{3:3}:
       __mutex_lock_common kernel/locking/mutex.c:968 [inline]
       __mutex_lock+0x13d/0x10b0 kernel/locking/mutex.c:1109
       hci_req_sync net/bluetooth/hci_request.c:275 [inline]
       bg_scan_update+0x82/0x500 net/bluetooth/hci_request.c:2895
       process_one_work+0x9a9/0x14b0 kernel/workqueue.c:2282
       worker_thread+0x61d/0x1310 kernel/workqueue.c:2428
       kthread+0x38f/0x470 kernel/kthread.c:313
       ret_from_fork+0x22/0x30 arch/x86/entry/entry_64.S:299

-> #0 ((work_completion)(&hdev->bg_scan_update)){+.+.}-{0:0}:
       check_prev_add kernel/locking/lockdep.c:2988 [inline]
       check_prevs_add kernel/locking/lockdep.c:3113 [inline]
       validate_chain kernel/locking/lockdep.c:3729 [inline]
       __lock_acquire+0x29e7/0x5b00 kernel/locking/lockdep.c:4955
       lock_acquire kernel/locking/lockdep.c:5566 [inline]
       lock_acquire+0x197/0x470 kernel/locking/lockdep.c:5531
       __flush_work+0x105/0xa90 kernel/workqueue.c:3053
       __cancel_work_timer+0x368/0x4c0 kernel/workqueue.c:3144
       hci_request_cancel_all+0x73/0x230 net/bluetooth/hci_request.c:3438
       hci_dev_do_close+0xd9/0x1240 net/bluetooth/hci_core.c:1733
       hci_rfkill_set_block+0x166/0x1a0 net/bluetooth/hci_core.c:2223
       rfkill_set_block+0x1fd/0x540 net/rfkill/core.c:341
       rfkill_fop_write+0x253/0x4b0 net/rfkill/core.c:1240
       vfs_write+0x29a/0xa70 fs/read_write.c:603
       ksys_write+0x1f6/0x260 fs/read_write.c:658
       do_syscall_64+0x33/0x40 arch/x86/entry/common.c:46
       entry_SYSCALL_64_after_hwframe+0x62/0xc7

other info that might help us debug this:

Chain exists of:
  (work_completion)(&hdev->bg_scan_update) --> &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((work_completion)(&hdev->bg_scan_update));

 *** DEADLOCK ***

1 lock held by syz-executor.2/9979:
 #0: ffffffff85619628 (rfkill_global_mutex){+.+.}-{3:3}, at: rfkill_fop_write+0xff/0x4b0 net/rfkill/core.c:1232

stack backtrace:
CPU: 1 PID: 9979 Comm: syz-executor.2 Not tainted 5.10.205 #1
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-1 04/01/2014
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x107/0x167 lib/dump_stack.c:118
 check_noncircular+0x263/0x2e0 kernel/locking/lockdep.c:2123
 check_prev_add kernel/locking/lockdep.c:2988 [inline]
 check_prevs_add kernel/locking/lockdep.c:3113 [inline]
 validate_chain kernel/locking/lockdep.c:3729 [inline]
 __lock_acquire+0x29e7/0x5b00 kernel/locking/lockdep.c:4955
 lock_acquire kernel/locking/lockdep.c:5566 [inline]
 lock_acquire+0x197/0x470 kernel/locking/lockdep.c:5531
 __flush_work+0x105/0xa90 kernel/workqueue.c:3053
 __cancel_work_timer+0x368/0x4c0 kernel/workqueue.c:3144
 hci_request_cancel_all+0x73/0x230 net/bluetooth/hci_request.c:3438
 hci_dev_do_close+0xd9/0x1240 net/bluetooth/hci_core.c:1733
 hci_rfkill_set_block+0x166/0x1a0 net/bluetooth/hci_core.c:2223
 rfkill_set_block+0x1fd/0x540 net/rfkill/core.c:341
 rfkill_fop_write+0x253/0x4b0 net/rfkill/core.c:1240
 vfs_write+0x29a/0xa70 fs/read_write.c:603
 ksys_write+0x1f6/0x260 fs/read_write.c:658
 do_syscall_64+0x33/0x40 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x62/0xc7
RIP: 0033:0x7fc516861b19
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fc513dd7188 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007fc516974f60 RCX: 00007fc516861b19
RDX: 0000000000000008 RSI: 00000000200000c0 RDI: 0000000000000004
RBP: 00007fc5168bbf6d R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffd44a359ef R14: 00007fc513dd7300 R15: 0000000000022000
EXT4-fs error (device loop6): ext4_ext_check_inode:500: inode #2: comm syz-executor.6: pblk 0 bad header/extent: invalid magic - magic 106, entries 17906, max 46329(0), depth 2055(2055)
EXT4-fs (loop6): get root inode failed
EXT4-fs (loop6): mount failed
FAULT_INJECTION: forcing a failure.
name failslab, interval 1, probability 0, space 0, times 0
CPU: 1 PID: 9989 Comm: syz-executor.5 Not tainted 5.10.205 #1
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-1 04/01/2014
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x107/0x167 lib/dump_stack.c:118
 fail_dump lib/fault-inject.c:52 [inline]
 should_fail.cold+0x5/0xa lib/fault-inject.c:146
 should_failslab+0x5/0x20 mm/slab_common.c:1193
 slab_pre_alloc_hook mm/slab.h:515 [inline]
 slab_alloc_node mm/slub.c:2821 [inline]
 slab_alloc mm/slub.c:2904 [inline]
 kmem_cache_alloc+0x5b/0x310 mm/slub.c:2909
 kmem_cache_zalloc include/linux/slab.h:654 [inline]
 lsm_file_alloc security/security.c:571 [inline]
 security_file_alloc+0x34/0x170 security/security.c:1472
 __alloc_file+0xb7/0x320 fs/file_table.c:106
 alloc_empty_file+0x6d/0x170 fs/file_table.c:151
 path_openat+0xe3/0x26e0 fs/namei.c:3417
 do_filp_open+0x190/0x3e0 fs/namei.c:3458
 do_sys_openat2+0x171/0x420 fs/open.c:1186
 do_sys_open fs/open.c:1202 [inline]
 __do_sys_openat fs/open.c:1218 [inline]
 __se_sys_openat fs/open.c:1213 [inline]
 __x64_sys_openat+0x13f/0x1f0 fs/open.c:1213
 do_syscall_64+0x33/0x40 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x62/0xc7
RIP: 0033:0x7f17f394ca04
Code: 84 00 00 00 00 00 44 89 54 24 0c e8 96 f9 ff ff 44 8b 54 24 0c 44 89 e2 48 89 ee 41 89 c0 bf 9c ff ff ff b8 01 01 00 00 0f 05 <48> 3d 00 f0 ff ff 77 34 44 89 c7 89 44 24 0c e8 c8 f9 ff ff 8b 44
RSP: 002b:00007f17f0f0eed0 EFLAGS: 00000293 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007f17f39e3970 RCX: 00007f17f394ca04
RDX: 0000000000000002 RSI: 00007f17f0f0f000 RDI: 00000000ffffff9c
RBP: 00007f17f0f0f000 R08: 0000000000000000 R09: ffffffffffffffff
R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000002
R13: 0000000000000004 R14: 00000000200004a0 R15: 0000000000000004
FAULT_INJECTION: forcing a failure.
name failslab, interval 1, probability 0, space 0, times 0
CPU: 0 PID: 9999 Comm: syz-executor.5 Not tainted 5.10.205 #1
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-1 04/01/2014
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x107/0x167 lib/dump_stack.c:118
 fail_dump lib/fault-inject.c:52 [inline]
 should_fail.cold+0x5/0xa lib/fault-inject.c:146
 should_failslab+0x5/0x20 mm/slab_common.c:1193
 slab_pre_alloc_hook mm/slab.h:515 [inline]
 slab_alloc_node mm/slub.c:2821 [inline]
 slab_alloc mm/slub.c:2904 [inline]
 kmem_cache_alloc_trace+0x55/0x320 mm/slub.c:2921
 kmalloc include/linux/slab.h:552 [inline]
 __kthread_create_on_node+0xd1/0x400 kernel/kthread.c:358
 kthread_create_on_node+0xbb/0x100 kernel/kthread.c:447
 loop_prepare_queue drivers/block/loop.c:931 [inline]
 loop_configure+0x3e3/0x1480 drivers/block/loop.c:1129
 lo_ioctl+0xa72/0x1760 drivers/block/loop.c:1687
 __blkdev_driver_ioctl block/ioctl.c:237 [inline]
 blkdev_ioctl+0x291/0x710 block/ioctl.c:632
 block_ioctl+0xf9/0x140 fs/block_dev.c:1893
 vfs_ioctl fs/ioctl.c:48 [inline]
 __do_sys_ioctl fs/ioctl.c:753 [inline]
 __se_sys_ioctl fs/ioctl.c:739 [inline]
 __x64_sys_ioctl+0x19a/0x210 fs/ioctl.c:739
 do_syscall_64+0x33/0x40 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x62/0xc7
RIP: 0033:0x7f17f39998d7
Code: 3c 1c 48 f7 d8 49 39 c4 72 b8 e8 a4 54 02 00 85 c0 78 bd 48 83 c4 08 4c 89 e0 5b 41 5c c3 0f 1f 44 00 00 b8 10 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f17f0f0ef48 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f17f39e3970 RCX: 00007f17f39998d7
RDX: 0000000000000004 RSI: 0000000000004c00 RDI: 0000000000000005
RBP: 0000000000000005 R08: 0000000000000000 R09: ffffffffffffffff
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000004
R13: 0000000000000004 R14: 00000000200004a0 R15: 0000000000000004
EXT4-fs error (device loop6): ext4_ext_check_inode:500: inode #2: comm syz-executor.6: pblk 0 bad header/extent: invalid magic - magic 106, entries 17906, max 46329(0), depth 2055(2055)
EXT4-fs (loop6): get root inode failed
EXT4-fs (loop6): mount failed