audit: type=1326 audit(1703765793.672:259): auid=0 uid=0 gid=0 ses=4 subj=system_u:system_r:kernel_t:s0 pid=7161 comm="syz-executor.1" exe="/syz-executor.1" sig=0 arch=c000003e syscall=18 compat=0 ip=0x7f1057afdab7 code=0x7ffc0000 ====================================================== WARNING: possible circular locking dependency detected 5.10.205 #1 Not tainted ------------------------------------------------------ syz-executor.3/7173 is trying to acquire lock: ffff888018100ae8 ((work_completion)(&hdev->tx_work)){+.+.}-{0:0}, at: __flush_work+0xdd/0xa90 kernel/workqueue.c:3050 but task is already holding lock: ffff888018100f40 (&hdev->req_lock){+.+.}-{3:3}, at: hci_dev_do_close+0xef/0x1240 net/bluetooth/hci_core.c:1734 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #3 (&hdev->req_lock){+.+.}-{3:3}: __mutex_lock_common kernel/locking/mutex.c:968 [inline] __mutex_lock+0x13d/0x10b0 kernel/locking/mutex.c:1109 hci_dev_do_close+0xef/0x1240 net/bluetooth/hci_core.c:1734 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 -> #2 (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 -> #1 (&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_sched_acl_pkt net/bluetooth/hci_core.c:4585 [inline] hci_sched_acl net/bluetooth/hci_core.c:4670 [inline] hci_tx_work+0x10af/0x1660 net/bluetooth/hci_core.c:4741 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->tx_work)){+.+.}-{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 hci_dev_do_close+0x131/0x1240 net/bluetooth/hci_core.c:1745 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->tx_work) --> rfkill_global_mutex --> &hdev->req_lock Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&hdev->req_lock); lock(rfkill_global_mutex); lock(&hdev->req_lock); lock((work_completion)(&hdev->tx_work)); *** DEADLOCK *** 2 locks held by syz-executor.3/7173: #0: ffffffff85619628 (rfkill_global_mutex){+.+.}-{3:3}, at: rfkill_fop_write+0xff/0x4b0 net/rfkill/core.c:1232 #1: ffff888018100f40 (&hdev->req_lock){+.+.}-{3:3}, at: hci_dev_do_close+0xef/0x1240 net/bluetooth/hci_core.c:1734 stack backtrace: CPU: 1 PID: 7173 Comm: syz-executor.3 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 hci_dev_do_close+0x131/0x1240 net/bluetooth/hci_core.c:1745 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: 0033:0x7fd7f3e9cb19 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:00007fd7f1412188 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007fd7f3faff60 RCX: 00007fd7f3e9cb19 RDX: 0000000000000008 RSI: 0000000020000080 RDI: 0000000000000003 RBP: 00007fd7f3ef6f6d R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffeaaff6c5f R14: 00007fd7f1412300 R15: 0000000000022000 audit: type=1326 audit(1703765793.672:260): auid=0 uid=0 gid=0 ses=4 subj=system_u:system_r:kernel_t:s0 pid=7161 comm="syz-executor.1" exe="/syz-executor.1" sig=0 arch=c000003e syscall=18 compat=0 ip=0x7f1057afdab7 code=0x7ffc0000 audit: type=1326 audit(1703765793.673:261): auid=0 uid=0 gid=0 ses=4 subj=system_u:system_r:kernel_t:s0 pid=7161 comm="syz-executor.1" exe="/syz-executor.1" sig=0 arch=c000003e syscall=257 compat=0 ip=0x7f1057afda04 code=0x7ffc0000 audit: type=1326 audit(1703765793.673:262): auid=0 uid=0 gid=0 ses=4 subj=system_u:system_r:kernel_t:s0 pid=7161 comm="syz-executor.1" exe="/syz-executor.1" sig=0 arch=c000003e syscall=3 compat=0 ip=0x7f1057afd72b code=0x7ffc0000 audit: type=1326 audit(1703765793.673:263): auid=0 uid=0 gid=0 ses=4 subj=system_u:system_r:kernel_t:s0 pid=7161 comm="syz-executor.1" exe="/syz-executor.1" sig=0 arch=c000003e syscall=202 compat=0 ip=0x7f1057b4ab19 code=0x7ffc0000 audit: type=1326 audit(1703765793.679:264): auid=0 uid=0 gid=0 ses=4 subj=system_u:system_r:kernel_t:s0 pid=7161 comm="syz-executor.1" exe="/syz-executor.1" sig=0 arch=c000003e syscall=1 compat=0 ip=0x7f1057b4ab19 code=0x7ffc0000 audit: type=1326 audit(1703765793.679:265): auid=0 uid=0 gid=0 ses=4 subj=system_u:system_r:kernel_t:s0 pid=7161 comm="syz-executor.1" exe="/syz-executor.1" sig=0 arch=c000003e syscall=202 compat=0 ip=0x7f1057b4ab19 code=0x7ffc0000 Restarting kernel threads ... done. Restarting kernel threads ... done. SELinux: unrecognized netlink message: protocol=0 nlmsg_type=0 sclass=netlink_route_socket pid=7196 comm=syz-executor.6 SELinux: unrecognized netlink message: protocol=0 nlmsg_type=0 sclass=netlink_route_socket pid=7198 comm=syz-executor.6