program: r0 = syz_init_net_socket$bt_l2cap(0x1f, 0x2, 0x0) r1 = socket$nl_generic(0x10, 0x3, 0x10) r2 = syz_genetlink_get_family_id$ethtool(&(0x7f0000000780), 0xffffffffffffffff) sendmsg$ETHTOOL_MSG_RINGS_SET(r1, &(0x7f0000000600)={0x0, 0x0, &(0x7f00000005c0)={&(0x7f0000000040)={0x3c, r2, 0x1, 0x0, 0x0, {}, [@ETHTOOL_A_RINGS_HEADER={0x18, 0x1, 0x0, 0x1, [@ETHTOOL_A_HEADER_DEV_NAME={0x14, 0x2, 'wlan0\x00'}]}, @ETHTOOL_A_RINGS_RX_JUMBO={0x8, 0x8, 0x800}, @ETHTOOL_A_RINGS_TX={0x8, 0x9, 0x1ff}]}, 0x3c}}, 0x0) connect$bt_l2cap(r0, &(0x7f0000000080)={0x1f, 0x0, @fixed={'\xaa\xaa\xaa\xaa\xaa', 0x10}, 0x7ff}, 0xe) r3 = syz_init_net_socket$bt_hidp(0x1f, 0x3, 0x6) ioctl$sock_bt_hidp_HIDPCONNADD(r3, 0x400448c8, &(0x7f0000000280)={r0, r0, 0xc, 0x1, &(0x7f0000000340)='\x00', 0x9, 0x1, 0x457, 0x9, 0x9, 0x1, 0x1, 'syz1\x00'}) r4 = syz_init_net_socket$bt_hci(0x1f, 0x3, 0x1) ioctl$sock_bt_hci(r4, 0x400448ca, 0x0) [ 86.020066][ T5326] hid-multitouch 0005:0457:0009.0002: unknown main item tag 0x0 [ 86.030819][ T5326] hid-multitouch 0005:0457:0009.0002: hidraw1: BLUETOOTH HID v0.09 Device [syz1] on aa:aa:aa:aa:aa:aa [ 86.072206][ T5329] [ 86.073425][ T5329] ====================================================== [ 86.076602][ T5329] WARNING: possible circular locking dependency detected [ 86.080330][ T5329] syzkaller #0 Not tainted [ 86.082633][ T5329] ------------------------------------------------------ [ 86.085664][ T5329] syz.0.0/5329 is trying to acquire lock: [ 86.088152][ T5329] ffff88804493f040 ((work_completion)(&(&conn->info_timer)->work)){+.+.}-{0:0}, at: __flush_work+0xd2/0xbc0 [ 86.093250][ T5329] [ 86.093250][ T5329] but task is already holding lock: [ 86.096926][ T5329] ffff88804493f338 (&conn->lock#2){+.+.}-{4:4}, at: l2cap_conn_del+0x70/0x680 [ 86.101600][ T5329] [ 86.101600][ T5329] which lock already depends on the new lock. [ 86.101600][ T5329] [ 86.106462][ T5329] [ 86.106462][ T5329] the existing dependency chain (in reverse order) is: [ 86.111041][ T5329] [ 86.111041][ T5329] -> #1 (&conn->lock#2){+.+.}-{4:4}: [ 86.114877][ T5329] lock_acquire+0x120/0x360 [ 86.117081][ T5329] __mutex_lock+0x187/0x1350 [ 86.119470][ T5329] l2cap_info_timeout+0x60/0xa0 [ 86.121557][ T5329] process_scheduled_works+0xae1/0x17b0 [ 86.124000][ T5329] worker_thread+0x8a0/0xda0 [ 86.126165][ T5329] kthread+0x711/0x8a0 [ 86.128145][ T5329] ret_from_fork+0x4bc/0x870 [ 86.130285][ T5329] ret_from_fork_asm+0x1a/0x30 [ 86.132503][ T5329] [ 86.132503][ T5329] -> #0 ((work_completion)(&(&conn->info_timer)->work)){+.+.}-{0:0}: [ 86.136737][ T5329] validate_chain+0xb9b/0x2140 [ 86.139075][ T5329] __lock_acquire+0xab9/0xd20 [ 86.141264][ T5329] lock_acquire+0x120/0x360 [ 86.143312][ T5329] __flush_work+0x6b8/0xbc0 [ 86.145227][ T5329] __cancel_work_sync+0xbe/0x110 [ 86.147465][ T5329] l2cap_conn_del+0x4f0/0x680 [ 86.149660][ T5329] hci_conn_hash_flush+0x10d/0x230 [ 86.151780][ T5329] hci_dev_close_sync+0xaef/0x1330 [ 86.153944][ T5329] hci_dev_close+0x108/0x200 [ 86.155936][ T5329] sock_do_ioctl+0xdc/0x300 [ 86.157786][ T5329] sock_ioctl+0x576/0x790 [ 86.159753][ T5329] __se_sys_ioctl+0xfc/0x170 [ 86.161820][ T5329] do_syscall_64+0xfa/0xfa0 [ 86.164190][ T5329] entry_SYSCALL_64_after_hwframe+0x77/0x7f [ 86.166748][ T5329] [ 86.166748][ T5329] other info that might help us debug this: [ 86.166748][ T5329] [ 86.170950][ T5329] Possible unsafe locking scenario: [ 86.170950][ T5329] [ 86.174266][ T5329] CPU0 CPU1 [ 86.176555][ T5329] ---- ---- [ 86.178556][ T5329] lock(&conn->lock#2); [ 86.180462][ T5329] lock((work_completion)(&(&conn->info_timer)->work)); [ 86.184768][ T5329] lock(&conn->lock#2); [ 86.187846][ T5329] lock((work_completion)(&(&conn->info_timer)->work)); [ 86.190975][ T5329] [ 86.190975][ T5329] *** DEADLOCK *** [ 86.190975][ T5329] [ 86.194366][ T5329] 5 locks held by syz.0.0/5329: [ 86.196321][ T5329] #0: ffff888035cccdc8 (&hdev->req_lock){+.+.}-{4:4}, at: hci_dev_close+0x100/0x200 [ 86.200079][ T5329] #1: ffff888035ccc0b8 (&hdev->lock){+.+.}-{4:4}, at: hci_dev_close_sync+0x66a/0x1330 [ 86.203919][ T5329] #2: ffffffff8f437268 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_conn_hash_flush+0xa1/0x230 [ 86.208011][ T5329] #3: ffff88804493f338 (&conn->lock#2){+.+.}-{4:4}, at: l2cap_conn_del+0x70/0x680 [ 86.212091][ T5329] #4: ffffffff8df3d2e0 (rcu_read_lock){....}-{1:3}, at: __flush_work+0xd2/0xbc0 [ 86.215993][ T5329] [ 86.215993][ T5329] stack backtrace: [ 86.218675][ T5329] CPU: 0 UID: 0 PID: 5329 Comm: syz.0.0 Not tainted syzkaller #0 PREEMPT(full) [ 86.218691][ T5329] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014 [ 86.218699][ T5329] Call Trace: [ 86.218707][ T5329] [ 86.218713][ T5329] dump_stack_lvl+0x189/0x250 [ 86.218734][ T5329] ? __pfx_dump_stack_lvl+0x10/0x10 [ 86.218750][ T5329] ? __pfx__printk+0x10/0x10 [ 86.218762][ T5329] ? print_lock_name+0xde/0x100 [ 86.218772][ T5329] print_circular_bug+0x2ee/0x310 [ 86.218786][ T5329] check_noncircular+0x134/0x160 [ 86.218800][ T5329] validate_chain+0xb9b/0x2140 [ 86.218811][ T5329] ? do_raw_spin_lock+0x121/0x290 [ 86.218825][ T5329] ? look_up_lock_class+0x74/0x170 [ 86.218838][ T5329] ? register_lock_class+0x51/0x320 [ 86.218848][ T5329] __lock_acquire+0xab9/0xd20 [ 86.218858][ T5329] ? __flush_work+0xd2/0xbc0 [ 86.218871][ T5329] lock_acquire+0x120/0x360 [ 86.218880][ T5329] ? __flush_work+0xd2/0xbc0 [ 86.218895][ T5329] ? _raw_spin_unlock_irq+0x23/0x50 [ 86.218907][ T5329] ? __flush_work+0xd2/0xbc0 [ 86.218919][ T5329] __flush_work+0x6b8/0xbc0 [ 86.218932][ T5329] ? __flush_work+0xd2/0xbc0 [ 86.218945][ T5329] ? __flush_work+0xd2/0xbc0 [ 86.218959][ T5329] ? __pfx___flush_work+0x10/0x10 [ 86.218972][ T5329] ? __pfx_wq_barrier_func+0x10/0x10 [ 86.218987][ T5329] ? __pfx___cancel_work+0x10/0x10 [ 86.218998][ T5329] ? hci_conn_drop+0x14d/0x280 [ 86.219008][ T5329] __cancel_work_sync+0xbe/0x110 [ 86.219020][ T5329] l2cap_conn_del+0x4f0/0x680 [ 86.219034][ T5329] ? __pfx_l2cap_disconn_cfm+0x10/0x10 [ 86.219050][ T5329] hci_conn_hash_flush+0x10d/0x230 [ 86.219067][ T5329] hci_dev_close_sync+0xaef/0x1330 [ 86.219085][ T5329] ? __pfx_hci_dev_close_sync+0x10/0x10 [ 86.219099][ T5329] ? do_raw_read_unlock+0x3d/0x80 [ 86.219115][ T5329] hci_dev_close+0x108/0x200 [ 86.219131][ T5329] sock_do_ioctl+0xdc/0x300 [ 86.219143][ T5329] ? __pfx_sock_do_ioctl+0x10/0x10 [ 86.219157][ T5329] sock_ioctl+0x576/0x790 [ 86.219169][ T5329] ? __pfx_sock_ioctl+0x10/0x10 [ 86.219180][ T5329] ? __fget_files+0x3a0/0x420 [ 86.219196][ T5329] ? __fget_files+0x2a/0x420 [ 86.219210][ T5329] ? bpf_lsm_file_ioctl+0x9/0x20 [ 86.219222][ T5329] ? __pfx_sock_ioctl+0x10/0x10 [ 86.219234][ T5329] __se_sys_ioctl+0xfc/0x170 [ 86.219248][ T5329] do_syscall_64+0xfa/0xfa0 [ 86.219262][ T5329] ? lockdep_hardirqs_on+0x9c/0x150 [ 86.219274][ T5329] ? entry_SYSCALL_64_after_hwframe+0x77/0x7f [ 86.219285][ T5329] ? clear_bhb_loop+0x60/0xb0 [ 86.219296][ T5329] entry_SYSCALL_64_after_hwframe+0x77/0x7f [ 86.219306][ T5329] RIP: 0033:0x7f09e818efc9 [ 86.219317][ T5329] 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 a8 ff ff ff f7 d8 64 89 01 48 [ 86.219325][ T5329] RSP: 002b:00007f09e90b4038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 [ 86.219338][ T5329] RAX: ffffffffffffffda RBX: 00007f09e83e6090 RCX: 00007f09e818efc9 [ 86.219346][ T5329] RDX: 0000000000000000 RSI: 00000000400448ca RDI: 0000000000000007 [ 86.219352][ T5329] RBP: 00007f09e8211f91 R08: 0000000000000000 R09: 0000000000000000 [ 86.219358][ T5329] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 [ 86.219363][ T5329] R13: 00007f09e83e6128 R14: 00007f09e83e6090 R15: 00007ffd4547d978 [ 86.219373][ T5329] [ 86.382646][ T5336] fido_id[5336]: Failed to open report descriptor at '/sys/devices/virtual/bluetooth/hci0/hci0:200/report_descriptor': No such file or directory [ 86.390232][ T4674] Bluetooth: hci0: command tx timeout [ 86.807972][ T9] cfg80211: failed to load regulatory.db [ 88.404688][ T4674] Bluetooth: hci0: command tx timeout [ 90.484722][ T4674] Bluetooth: hci0: command tx timeout