program: r0 = syz_init_net_socket$bt_l2cap(0x1f, 0x1, 0x3) bind$bt_l2cap(r0, &(0x7f00000000c0), 0xe) r1 = syz_init_net_socket$bt_l2cap(0x1f, 0x2, 0x0) connect$bt_l2cap(r1, &(0x7f0000000080)={0x1f, 0x0, @fixed={'\xaa\xaa\xaa\xaa\xaa', 0x10}, 0x7ff}, 0xe) r2 = syz_init_net_socket$bt_hidp(0x1f, 0x3, 0x6) ioctl$sock_bt_hidp_HIDPCONNADD(r2, 0x400448c8, &(0x7f0000000280)={r1, r1, 0xc, 0x1, &(0x7f0000000340)='\x00', 0x9, 0x1, 0x457, 0x9, 0x9, 0x1, 0x1, 'syz1\x00'}) r3 = syz_init_net_socket$bt_hci(0x1f, 0x3, 0x1) ioctl$sock_bt_hci(r3, 0x400448ca, 0x0) listen(r0, 0x0) ioctl$sock_SIOCOUTQ(r0, 0x5411, 0x0) sendmsg$nl_route_sched(0xffffffffffffffff, &(0x7f0000000100)={0x0, 0x0, &(0x7f00000000c0)={&(0x7f0000006540)=@newtaction={0x60, 0x30, 0xb, 0x0, 0x25dfdbff, {}, [{0x4c, 0x1, [@m_gact={0x48, 0x1, 0x0, 0x0, {{0x9}, {0x1c, 0x2, 0x0, 0x1, [@TCA_GACT_PARMS={0x18, 0x2, {0x0, 0x0, 0x20000000}}]}, {0x4}, {0xc}, {0xc}}}]}]}, 0x60}}, 0x0) [ 85.136167][ T5306] hid-multitouch 0005:0457:0009.0002: unknown main item tag 0x0 [ 85.183482][ T5306] hid-multitouch 0005:0457:0009.0002: hidraw1: BLUETOOTH HID v0.09 Device [syz1] on aa:aa:aa:aa:aa:aa [ 85.230938][ T5321] [ 85.232053][ T5321] ====================================================== [ 85.234934][ T5321] WARNING: possible circular locking dependency detected [ 85.237957][ T5321] syzkaller #0 Not tainted [ 85.239855][ T5321] ------------------------------------------------------ [ 85.242809][ T5321] syz.0.0/5321 is trying to acquire lock: [ 85.245179][ T5321] ffff88804124b840 ((work_completion)(&(&conn->info_timer)->work)){+.+.}-{0:0}, at: __flush_work+0x100/0xc50 [ 85.250868][ T5321] [ 85.250868][ T5321] but task is already holding lock: [ 85.255890][ T5321] ffff88804124bb38 (&conn->lock#2){+.+.}-{4:4}, at: l2cap_conn_del+0x7b/0x5b0 [ 85.259884][ T5321] [ 85.259884][ T5321] which lock already depends on the new lock. [ 85.259884][ T5321] [ 85.264231][ T5321] [ 85.264231][ T5321] the existing dependency chain (in reverse order) is: [ 85.268163][ T5321] [ 85.268163][ T5321] -> #1 (&conn->lock#2){+.+.}-{4:4}: [ 85.271481][ T5321] __mutex_lock+0x19f/0x1300 [ 85.273682][ T5321] l2cap_info_timeout+0x60/0xa0 [ 85.275904][ T5321] process_scheduled_works+0xaec/0x17a0 [ 85.278571][ T5321] worker_thread+0xda6/0x1360 [ 85.280827][ T5321] kthread+0x726/0x8b0 [ 85.282704][ T5321] ret_from_fork+0x51b/0xa40 [ 85.284760][ T5321] ret_from_fork_asm+0x1a/0x30 [ 85.286934][ T5321] [ 85.286934][ T5321] -> #0 ((work_completion)(&(&conn->info_timer)->work)){+.+.}-{0:0}: [ 85.290938][ T5321] __lock_acquire+0x15a5/0x2cf0 [ 85.293185][ T5321] lock_acquire+0x106/0x330 [ 85.295317][ T5321] __flush_work+0x700/0xc50 [ 85.297541][ T5321] __cancel_work_sync+0xbe/0x110 [ 85.299834][ T5321] l2cap_conn_del+0x402/0x5b0 [ 85.302034][ T5321] hci_conn_hash_flush+0x10d/0x260 [ 85.304485][ T5321] hci_dev_close_sync+0x821/0x10e0 [ 85.306850][ T5321] hci_dev_close+0x108/0x260 [ 85.308949][ T5321] sock_do_ioctl+0x101/0x320 [ 85.311165][ T5321] sock_ioctl+0x5c6/0x7f0 [ 85.313352][ T5321] __se_sys_ioctl+0xfc/0x170 [ 85.315546][ T5321] do_syscall_64+0xe2/0xf80 [ 85.317746][ T5321] entry_SYSCALL_64_after_hwframe+0x77/0x7f [ 85.320495][ T5321] [ 85.320495][ T5321] other info that might help us debug this: [ 85.320495][ T5321] [ 85.324771][ T5321] Possible unsafe locking scenario: [ 85.324771][ T5321] [ 85.327840][ T5321] CPU0 CPU1 [ 85.330044][ T5321] ---- ---- [ 85.332337][ T5321] lock(&conn->lock#2); [ 85.334204][ T5321] lock((work_completion)(&(&conn->info_timer)->work)); [ 85.338294][ T5321] lock(&conn->lock#2); [ 85.341339][ T5321] lock((work_completion)(&(&conn->info_timer)->work)); [ 85.344350][ T5321] [ 85.344350][ T5321] *** DEADLOCK *** [ 85.344350][ T5321] [ 85.347775][ T5321] 5 locks held by syz.0.0/5321: [ 85.349846][ T5321] #0: ffff88801a650ec0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_dev_close+0x100/0x260 [ 85.353930][ T5321] #1: ffff88801a6500c0 (&hdev->lock){+.+.}-{4:4}, at: hci_dev_close_sync+0x640/0x10e0 [ 85.358174][ T5321] #2: ffffffff8fb3b1e8 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_conn_hash_flush+0xa1/0x260 [ 85.362578][ T5321] #3: ffff88804124bb38 (&conn->lock#2){+.+.}-{4:4}, at: l2cap_conn_del+0x7b/0x5b0 [ 85.366637][ T5321] #4: ffffffff8e55a360 (rcu_read_lock){....}-{1:3}, at: __flush_work+0x100/0xc50 [ 85.370801][ T5321] [ 85.370801][ T5321] stack backtrace: [ 85.373588][ T5321] CPU: 0 UID: 0 PID: 5321 Comm: syz.0.0 Not tainted syzkaller #0 PREEMPT(full) [ 85.373616][ T5321] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014 [ 85.373635][ T5321] Call Trace: [ 85.373804][ T5321] [ 85.373828][ T5321] dump_stack_lvl+0xe8/0x150 [ 85.373865][ T5321] print_circular_bug+0x2e1/0x300 [ 85.373906][ T5321] check_noncircular+0x12e/0x150 [ 85.373922][ T5321] __lock_acquire+0x15a5/0x2cf0 [ 85.373943][ T5321] ? do_raw_spin_lock+0x12b/0x2f0 [ 85.373973][ T5321] ? __flush_work+0x100/0xc50 [ 85.373985][ T5321] lock_acquire+0x106/0x330 [ 85.374003][ T5321] ? __flush_work+0x100/0xc50 [ 85.374018][ T5321] ? __flush_work+0x100/0xc50 [ 85.374030][ T5321] __flush_work+0x700/0xc50 [ 85.374041][ T5321] ? __flush_work+0x100/0xc50 [ 85.374052][ T5321] ? __flush_work+0x100/0xc50 [ 85.374064][ T5321] ? __pfx___flush_work+0x10/0x10 [ 85.374075][ T5321] ? __pfx_wq_barrier_func+0x10/0x10 [ 85.374095][ T5321] ? __cancel_work_sync+0x5c/0x110 [ 85.374108][ T5321] __cancel_work_sync+0xbe/0x110 [ 85.374120][ T5321] l2cap_conn_del+0x402/0x5b0 [ 85.374162][ T5321] ? __pfx_l2cap_disconn_cfm+0x10/0x10 [ 85.374176][ T5321] hci_conn_hash_flush+0x10d/0x260 [ 85.374192][ T5321] hci_dev_close_sync+0x821/0x10e0 [ 85.374202][ T5321] ? __pfx_hci_dev_close_sync+0x10/0x10 [ 85.374211][ T5321] ? lockdep_hardirqs_on+0x7a/0x110 [ 85.374222][ T5321] ? enable_work+0x1fd/0x230 [ 85.374235][ T5321] hci_dev_close+0x108/0x260 [ 85.374246][ T5321] sock_do_ioctl+0x101/0x320 [ 85.374283][ T5321] ? __pfx_sock_do_ioctl+0x10/0x10 [ 85.374300][ T5321] ? do_futex+0x395/0x420 [ 85.374322][ T5321] sock_ioctl+0x5c6/0x7f0 [ 85.374336][ T5321] ? __pfx_sock_ioctl+0x10/0x10 [ 85.374350][ T5321] ? __fget_files+0x2a/0x420 [ 85.374362][ T5321] ? __fget_files+0x3a0/0x420 [ 85.374372][ T5321] ? __fget_files+0x2a/0x420 [ 85.374383][ T5321] ? bpf_lsm_file_ioctl+0x9/0x20 [ 85.374396][ T5321] ? __pfx_sock_ioctl+0x10/0x10 [ 85.374418][ T5321] __se_sys_ioctl+0xfc/0x170 [ 85.374494][ T5321] do_syscall_64+0xe2/0xf80 [ 85.374523][ T5321] ? entry_SYSCALL_64_after_hwframe+0x77/0x7f [ 85.374535][ T5321] ? trace_irq_disable+0x37/0x100 [ 85.374548][ T5321] ? clear_bhb_loop+0x60/0xb0 [ 85.374561][ T5321] entry_SYSCALL_64_after_hwframe+0x77/0x7f [ 85.374594][ T5321] RIP: 0033:0x7f9f3279aeb9 [ 85.374660][ T5321] 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 [ 85.374673][ T5321] RSP: 002b:00007f9f3370d028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 [ 85.374703][ T5321] RAX: ffffffffffffffda RBX: 00007f9f32a15fa0 RCX: 00007f9f3279aeb9 [ 85.374713][ T5321] RDX: 0000000000000000 RSI: 00000000400448ca RDI: 0000000000000007 [ 85.374721][ T5321] RBP: 00007f9f32808c1f R08: 0000000000000000 R09: 0000000000000000 [ 85.374729][ T5321] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 [ 85.374737][ T5321] R13: 00007f9f32a16038 R14: 00007f9f32a15fa0 R15: 00007ffd6adcb168 [ 85.374751][ T5321] [ 85.533323][ T5298] Bluetooth: hci0: command tx timeout [ 85.541970][ T5328] fido_id[5328]: Failed to open report descriptor at '/sys/devices/virtual/bluetooth/hci0/hci0:200/report_descriptor': No such file or directory [ 87.609493][ T5298] Bluetooth: hci0: command tx timeout [ 89.689870][ T5298] Bluetooth: hci0: command tx timeout