program: r0 = syz_init_net_socket$bt_l2cap(0x1f, 0x2, 0x0) connect$bt_l2cap(r0, &(0x7f0000000080)={0x1f, 0x0, @fixed={'\xaa\xaa\xaa\xaa\xaa', 0x10}, 0x7ff}, 0xe) r1 = syz_init_net_socket$bt_hidp(0x1f, 0x3, 0x6) ioctl$sock_bt_hidp_HIDPCONNADD(r1, 0x400448c8, &(0x7f0000000280)={r0, r0, 0xc, 0x1, &(0x7f0000000340)='\x00', 0x9, 0x1, 0x457, 0x7, 0x9, 0x1, 0x1, 'syz1\x00'}) r2 = syz_init_net_socket$bt_hci(0x1f, 0x3, 0x1) ioctl$sock_bt_hci(r2, 0x400448ca, 0x0) [ 85.578954][ T5304] Bluetooth: hci0: command tx timeout [ 85.683858][ T4729] hid-multitouch 0005:0457:0007.0002: unknown main item tag 0x0 [ 85.711007][ T4729] hid-multitouch 0005:0457:0007.0002: hidraw1: BLUETOOTH HID v0.09 Device [syz1] on aa:aa:aa:aa:aa:aa [ 85.763165][ T5329] [ 85.764265][ T5329] ====================================================== [ 85.767489][ T5329] WARNING: possible circular locking dependency detected [ 85.770754][ T5329] syzkaller #0 Not tainted [ 85.772722][ T5329] ------------------------------------------------------ [ 85.776329][ T5329] syz.0.0/5329 is trying to acquire lock: [ 85.779421][ T5329] ffff888034a1e840 ((work_completion)(&(&conn->info_timer)->work)){+.+.}-{0:0}, at: __flush_work+0x100/0xc50 [ 85.784824][ T5329] [ 85.784824][ T5329] but task is already holding lock: [ 85.788245][ T5329] ffff888034a1eaf8 (&conn->lock#2){+.+.}-{4:4}, at: l2cap_conn_del+0x7b/0x5c0 [ 85.792557][ T5329] [ 85.792557][ T5329] which lock already depends on the new lock. [ 85.792557][ T5329] [ 85.797216][ T5329] [ 85.797216][ T5329] the existing dependency chain (in reverse order) is: [ 85.801441][ T5329] [ 85.801441][ T5329] -> #1 (&conn->lock#2){+.+.}-{4:4}: [ 85.804996][ T5329] __mutex_lock+0x19f/0x1300 [ 85.807316][ T5329] l2cap_info_timeout+0x60/0xa0 [ 85.809986][ T5329] process_scheduled_works+0xb02/0x1830 [ 85.812837][ T5329] worker_thread+0xa50/0xfc0 [ 85.815279][ T5329] kthread+0x388/0x470 [ 85.817528][ T5329] ret_from_fork+0x51e/0xb90 [ 85.819892][ T5329] ret_from_fork_asm+0x1a/0x30 [ 85.822375][ T5329] [ 85.822375][ T5329] -> #0 ((work_completion)(&(&conn->info_timer)->work)){+.+.}-{0:0}: [ 85.827204][ T5329] __lock_acquire+0x15a5/0x2cf0 [ 85.829772][ T5329] lock_acquire+0xf0/0x2e0 [ 85.832206][ T5329] __flush_work+0x700/0xc50 [ 85.834586][ T5329] __cancel_work_sync+0xbe/0x110 [ 85.837191][ T5329] l2cap_conn_del+0x40f/0x5c0 [ 85.839650][ T5329] hci_conn_hash_flush+0x10d/0x260 [ 85.842457][ T5329] hci_dev_close_sync+0x821/0x10e0 [ 85.845105][ T5329] hci_dev_close+0x108/0x260 [ 85.847478][ T5329] sock_do_ioctl+0x101/0x320 [ 85.849896][ T5329] sock_ioctl+0x5c6/0x7f0 [ 85.852309][ T5329] __se_sys_ioctl+0xfc/0x170 [ 85.854789][ T5329] do_syscall_64+0x14d/0xf80 [ 85.857177][ T5329] entry_SYSCALL_64_after_hwframe+0x77/0x7f [ 85.860251][ T5329] [ 85.860251][ T5329] other info that might help us debug this: [ 85.860251][ T5329] [ 85.865771][ T5329] Possible unsafe locking scenario: [ 85.865771][ T5329] [ 85.869462][ T5329] CPU0 CPU1 [ 85.872098][ T5329] ---- ---- [ 85.874914][ T5329] lock(&conn->lock#2); [ 85.876912][ T5329] lock((work_completion)(&(&conn->info_timer)->work)); [ 85.881157][ T5329] lock(&conn->lock#2); [ 85.884103][ T5329] lock((work_completion)(&(&conn->info_timer)->work)); [ 85.887228][ T5329] [ 85.887228][ T5329] *** DEADLOCK *** [ 85.887228][ T5329] [ 85.890833][ T5329] 5 locks held by syz.0.0/5329: [ 85.893306][ T5329] #0: ffff888011ce4ec0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_dev_close+0x100/0x260 [ 85.897651][ T5329] #1: ffff888011ce40c0 (&hdev->lock){+.+.}-{4:4}, at: hci_dev_close_sync+0x640/0x10e0 [ 85.901899][ T5329] #2: ffffffff8fd5c4e8 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_conn_hash_flush+0xa1/0x260 [ 85.906360][ T5329] #3: ffff888034a1eaf8 (&conn->lock#2){+.+.}-{4:4}, at: l2cap_conn_del+0x7b/0x5c0 [ 85.910401][ T5329] #4: ffffffff8e75e420 (rcu_read_lock){....}-{1:3}, at: __flush_work+0x100/0xc50 [ 85.915541][ T5329] [ 85.915541][ T5329] stack backtrace: [ 85.919345][ T5329] CPU: 0 UID: 0 PID: 5329 Comm: syz.0.0 Not tainted syzkaller #0 PREEMPT(full) [ 85.919367][ T5329] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014 [ 85.919377][ T5329] Call Trace: [ 85.919387][ T5329] [ 85.919395][ T5329] dump_stack_lvl+0xe8/0x150 [ 85.919422][ T5329] print_circular_bug+0x2e1/0x300 [ 85.919448][ T5329] check_noncircular+0x12e/0x150 [ 85.919466][ T5329] __lock_acquire+0x15a5/0x2cf0 [ 85.919483][ T5329] ? do_raw_spin_lock+0x12b/0x2f0 [ 85.919498][ T5329] ? do_raw_spin_unlock+0x4d/0x210 [ 85.919512][ T5329] lock_acquire+0xf0/0x2e0 [ 85.919525][ T5329] ? __flush_work+0x100/0xc50 [ 85.919543][ T5329] ? __flush_work+0x100/0xc50 [ 85.919560][ T5329] __flush_work+0x700/0xc50 [ 85.919577][ T5329] ? __flush_work+0x100/0xc50 [ 85.919595][ T5329] ? __flush_work+0x100/0xc50 [ 85.919610][ T5329] ? __pfx___flush_work+0x10/0x10 [ 85.919620][ T5329] ? __pfx_wq_barrier_func+0x10/0x10 [ 85.919634][ T5329] ? __cancel_work_sync+0x5c/0x110 [ 85.919645][ T5329] __cancel_work_sync+0xbe/0x110 [ 85.919657][ T5329] l2cap_conn_del+0x40f/0x5c0 [ 85.919671][ T5329] ? __pfx_l2cap_disconn_cfm+0x10/0x10 [ 85.919681][ T5329] hci_conn_hash_flush+0x10d/0x260 [ 85.919694][ T5329] hci_dev_close_sync+0x821/0x10e0 [ 85.919710][ T5329] ? __pfx_hci_dev_close_sync+0x10/0x10 [ 85.919724][ T5329] ? lockdep_hardirqs_on+0x7a/0x110 [ 85.919736][ T5329] ? enable_work+0x1fd/0x230 [ 85.919756][ T5329] hci_dev_close+0x108/0x260 [ 85.919773][ T5329] sock_do_ioctl+0x101/0x320 [ 85.919789][ T5329] ? __pfx_sock_do_ioctl+0x10/0x10 [ 85.919801][ T5329] ? do_futex+0x395/0x420 [ 85.919814][ T5329] sock_ioctl+0x5c6/0x7f0 [ 85.919823][ T5329] ? __pfx_sock_ioctl+0x10/0x10 [ 85.919831][ T5329] ? __fget_files+0x2a/0x420 [ 85.919847][ T5329] ? __fget_files+0x3a0/0x420 [ 85.919861][ T5329] ? __fget_files+0x2a/0x420 [ 85.919878][ T5329] ? bpf_lsm_file_ioctl+0x9/0x20 [ 85.919894][ T5329] ? __pfx_sock_ioctl+0x10/0x10 [ 85.919909][ T5329] __se_sys_ioctl+0xfc/0x170 [ 85.919923][ T5329] do_syscall_64+0x14d/0xf80 [ 85.919935][ T5329] ? trace_irq_disable+0x3b/0x150 [ 85.919953][ T5329] ? entry_SYSCALL_64_after_hwframe+0x77/0x7f [ 85.919966][ T5329] ? clear_bhb_loop+0x40/0x90 [ 85.919979][ T5329] entry_SYSCALL_64_after_hwframe+0x77/0x7f [ 85.919991][ T5329] RIP: 0033:0x7fd14419c799 [ 85.920005][ T5329] Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48 [ 85.920015][ T5329] RSP: 002b:00007fd1450eafe8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 [ 85.920032][ T5329] RAX: ffffffffffffffda RBX: 00007fd144415fa0 RCX: 00007fd14419c799 [ 85.920043][ T5329] RDX: 0000000000000000 RSI: 00000000400448ca RDI: 0000000000000006 [ 85.920052][ T5329] RBP: 00007fd144232c99 R08: 0000000000000000 R09: 0000000000000000 [ 85.920060][ T5329] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 [ 85.920068][ T5329] R13: 00007fd144416038 R14: 00007fd144415fa0 R15: 00007ffda1a4b058 [ 85.920082][ T5329] [ 86.096810][ T5333] fido_id[5333]: Failed to open report descriptor at '/sys/devices/virtual/bluetooth/hci0/hci0:200/report_descriptor': No such file or directory [ 87.598303][ T4668] Bluetooth: hci0: command tx timeout [ 89.678990][ T4668] Bluetooth: hci0: command tx timeout [ 91.758291][ T4668] Bluetooth: hci0: command tx timeout [ 92.013397][ T922] cfg80211: failed to load regulatory.db