program: setsockopt$netlink_NETLINK_TX_RING(0xffffffffffffffff, 0x10e, 0xc, 0x0, 0x0) r0 = syz_init_net_socket$bt_hci(0x1f, 0x3, 0x1) 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'}) ioctl$sock_bt_hci(r0, 0x400448ca, 0x0) getsockopt$bt_BT_CHANNEL_POLICY(r0, 0x112, 0xa, &(0x7f0000000000)=0x9, &(0x7f0000000040)=0x4) [ 85.898479][ T5308] Bluetooth: hci0: command tx timeout [ 86.023732][ T793] hid-multitouch 0005:0457:0009.0002: unknown main item tag 0x0 [ 86.043323][ T793] hid-multitouch 0005:0457:0009.0002: hidraw1: BLUETOOTH HID v0.09 Device [syz1] on aa:aa:aa:aa:aa:aa [ 86.091117][ T5334] [ 86.092409][ T5334] ====================================================== [ 86.095867][ T5334] WARNING: possible circular locking dependency detected [ 86.099029][ T5334] 6.16.0-rc1-syzkaller-00239-g08215f5486ec #0 Not tainted [ 86.102079][ T5334] ------------------------------------------------------ [ 86.105111][ T5334] syz.0.0/5334 is trying to acquire lock: [ 86.107962][ T5334] ffff8880123cf840 ((work_completion)(&(&conn->info_timer)->work)){+.+.}-{0:0}, at: __flush_work+0xd2/0xbc0 [ 86.113917][ T5334] [ 86.113917][ T5334] but task is already holding lock: [ 86.116993][ T5334] ffff8880123cfb38 (&conn->lock#2){+.+.}-{4:4}, at: l2cap_conn_del+0x70/0x680 [ 86.121039][ T5334] [ 86.121039][ T5334] which lock already depends on the new lock. [ 86.121039][ T5334] [ 86.125517][ T5334] [ 86.125517][ T5334] the existing dependency chain (in reverse order) is: [ 86.129666][ T5334] [ 86.129666][ T5334] -> #1 (&conn->lock#2){+.+.}-{4:4}: [ 86.133983][ T5334] lock_acquire+0x120/0x360 [ 86.136328][ T5334] __mutex_lock+0x182/0xe80 [ 86.138443][ T5334] l2cap_info_timeout+0x60/0xa0 [ 86.140563][ T5334] process_scheduled_works+0xae1/0x17b0 [ 86.143019][ T5334] worker_thread+0x8a0/0xda0 [ 86.145130][ T5334] kthread+0x70e/0x8a0 [ 86.147036][ T5334] ret_from_fork+0x3fc/0x770 [ 86.149324][ T5334] ret_from_fork_asm+0x1a/0x30 [ 86.152151][ T5334] [ 86.152151][ T5334] -> #0 ((work_completion)(&(&conn->info_timer)->work)){+.+.}-{0:0}: [ 86.157136][ T5334] validate_chain+0xb9b/0x2140 [ 86.159512][ T5334] __lock_acquire+0xab9/0xd20 [ 86.161697][ T5334] lock_acquire+0x120/0x360 [ 86.163837][ T5334] __flush_work+0x6b8/0xbc0 [ 86.166294][ T5334] __cancel_work_sync+0xbe/0x110 [ 86.170704][ T5334] l2cap_conn_del+0x4f0/0x680 [ 86.173107][ T5334] hci_conn_hash_flush+0x10d/0x230 [ 86.175504][ T5334] hci_dev_close_sync+0xaef/0x1330 [ 86.177913][ T5334] hci_dev_close+0x106/0x200 [ 86.180024][ T5334] sock_do_ioctl+0xdc/0x300 [ 86.182103][ T5334] sock_ioctl+0x576/0x790 [ 86.184369][ T5334] __se_sys_ioctl+0xf9/0x170 [ 86.187240][ T5334] do_syscall_64+0xfa/0x3b0 [ 86.190383][ T5334] entry_SYSCALL_64_after_hwframe+0x77/0x7f [ 86.194002][ T5334] [ 86.194002][ T5334] other info that might help us debug this: [ 86.194002][ T5334] [ 86.198725][ T5334] Possible unsafe locking scenario: [ 86.198725][ T5334] [ 86.201915][ T5334] CPU0 CPU1 [ 86.204300][ T5334] ---- ---- [ 86.206621][ T5334] lock(&conn->lock#2); [ 86.208503][ T5334] lock((work_completion)(&(&conn->info_timer)->work)); [ 86.212625][ T5334] lock(&conn->lock#2); [ 86.215690][ T5334] lock((work_completion)(&(&conn->info_timer)->work)); [ 86.219045][ T5334] [ 86.219045][ T5334] *** DEADLOCK *** [ 86.219045][ T5334] [ 86.222270][ T5334] 5 locks held by syz.0.0/5334: [ 86.224208][ T5334] #0: ffff88804212cd80 (&hdev->req_lock){+.+.}-{4:4}, at: hci_dev_close+0xfe/0x200 [ 86.228383][ T5334] #1: ffff88804212c078 (&hdev->lock){+.+.}-{4:4}, at: hci_dev_close_sync+0x66a/0x1330 [ 86.233308][ T5334] #2: ffffffff8f678228 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_conn_hash_flush+0xa1/0x230 [ 86.237780][ T5334] #3: ffff8880123cfb38 (&conn->lock#2){+.+.}-{4:4}, at: l2cap_conn_del+0x70/0x680 [ 86.242349][ T5334] #4: ffffffff8e13ed60 (rcu_read_lock){....}-{1:3}, at: __flush_work+0xd2/0xbc0 [ 86.247211][ T5334] [ 86.247211][ T5334] stack backtrace: [ 86.249897][ T5334] CPU: 0 UID: 0 PID: 5334 Comm: syz.0.0 Not tainted 6.16.0-rc1-syzkaller-00239-g08215f5486ec #0 PREEMPT(full) [ 86.249917][ T5334] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014 [ 86.249926][ T5334] Call Trace: [ 86.249934][ T5334] [ 86.249942][ T5334] dump_stack_lvl+0x189/0x250 [ 86.249967][ T5334] ? __pfx_dump_stack_lvl+0x10/0x10 [ 86.249983][ T5334] ? __pfx__printk+0x10/0x10 [ 86.249998][ T5334] ? print_lock_name+0xde/0x100 [ 86.250009][ T5334] print_circular_bug+0x2ee/0x310 [ 86.250024][ T5334] check_noncircular+0x134/0x160 [ 86.250037][ T5334] validate_chain+0xb9b/0x2140 [ 86.250049][ T5334] ? do_raw_spin_lock+0x121/0x290 [ 86.250064][ T5334] ? look_up_lock_class+0x74/0x170 [ 86.250084][ T5334] ? register_lock_class+0x51/0x320 [ 86.250102][ T5334] __lock_acquire+0xab9/0xd20 [ 86.250121][ T5334] ? __flush_work+0xd2/0xbc0 [ 86.250134][ T5334] lock_acquire+0x120/0x360 [ 86.250150][ T5334] ? __flush_work+0xd2/0xbc0 [ 86.250161][ T5334] ? _raw_spin_unlock_irq+0x23/0x50 [ 86.250174][ T5334] ? __flush_work+0xd2/0xbc0 [ 86.250186][ T5334] __flush_work+0x6b8/0xbc0 [ 86.250198][ T5334] ? __flush_work+0xd2/0xbc0 [ 86.250209][ T5334] ? __flush_work+0xd2/0xbc0 [ 86.250221][ T5334] ? __pfx___flush_work+0x10/0x10 [ 86.250233][ T5334] ? __pfx_wq_barrier_func+0x10/0x10 [ 86.250254][ T5334] ? __pfx___cancel_work+0x10/0x10 [ 86.250267][ T5334] ? hci_conn_drop+0x14d/0x280 [ 86.250295][ T5334] __cancel_work_sync+0xbe/0x110 [ 86.250309][ T5334] l2cap_conn_del+0x4f0/0x680 [ 86.250326][ T5334] ? __pfx_l2cap_disconn_cfm+0x10/0x10 [ 86.250340][ T5334] hci_conn_hash_flush+0x10d/0x230 [ 86.250354][ T5334] hci_dev_close_sync+0xaef/0x1330 [ 86.250370][ T5334] ? __pfx_hci_dev_close_sync+0x10/0x10 [ 86.250386][ T5334] hci_dev_close+0x106/0x200 [ 86.250402][ T5334] sock_do_ioctl+0xdc/0x300 [ 86.250421][ T5334] ? __pfx_sock_do_ioctl+0x10/0x10 [ 86.250438][ T5334] ? __lock_acquire+0xab9/0xd20 [ 86.250458][ T5334] sock_ioctl+0x576/0x790 [ 86.250476][ T5334] ? __pfx_sock_ioctl+0x10/0x10 [ 86.250493][ T5334] ? __fget_files+0x2a/0x420 [ 86.250505][ T5334] ? __fget_files+0x3a0/0x420 [ 86.250515][ T5334] ? __fget_files+0x2a/0x420 [ 86.250529][ T5334] ? bpf_lsm_file_ioctl+0x9/0x20 [ 86.250549][ T5334] ? __pfx_sock_ioctl+0x10/0x10 [ 86.250567][ T5334] __se_sys_ioctl+0xf9/0x170 [ 86.250582][ T5334] do_syscall_64+0xfa/0x3b0 [ 86.250592][ T5334] ? lockdep_hardirqs_on+0x9c/0x150 [ 86.250606][ T5334] ? entry_SYSCALL_64_after_hwframe+0x77/0x7f [ 86.250619][ T5334] ? clear_bhb_loop+0x60/0xb0 [ 86.250631][ T5334] entry_SYSCALL_64_after_hwframe+0x77/0x7f [ 86.250641][ T5334] RIP: 0033:0x7fcc72b8e929 [ 86.250677][ T5334] 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 [ 86.250687][ T5334] RSP: 002b:00007fcc739b6038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 [ 86.250701][ T5334] RAX: ffffffffffffffda RBX: 00007fcc72db5fa0 RCX: 00007fcc72b8e929 [ 86.250709][ T5334] RDX: 0000000000000000 RSI: 00000000400448ca RDI: 0000000000000004 [ 86.250715][ T5334] RBP: 00007fcc72c10b39 R08: 0000000000000000 R09: 0000000000000000 [ 86.250721][ T5334] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 [ 86.250728][ T5334] R13: 0000000000000000 R14: 00007fcc72db5fa0 R15: 00007ffd372fa9f8 [ 86.250739][ T5334] [ 86.422557][ T5338] fido_id[5338]: Failed to open report descriptor at '/sys/devices/virtual/bluetooth/hci0/hci0:200/report_descriptor': No such file or directory [ 86.682282][ T9] cfg80211: failed to load regulatory.db [ 87.958764][ T4674] Bluetooth: hci0: command tx timeout [ 90.039305][ T4674] Bluetooth: hci0: command tx timeout [ 92.118665][ T4674] Bluetooth: hci0: command tx timeout