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) [ 86.202049][ T5324] Bluetooth: hci0: command tx timeout [ 86.284234][ T792] hid-multitouch 0005:0457:0009.0002: unknown main item tag 0x0 [ 86.309026][ T792] hid-multitouch 0005:0457:0009.0002: hidraw1: BLUETOOTH HID v0.09 Device [syz1] on aa:aa:aa:aa:aa:aa [ 86.350191][ T5349] [ 86.351345][ T5349] ====================================================== [ 86.354201][ T5349] WARNING: possible circular locking dependency detected [ 86.357292][ T5349] 6.16.0-rc6-syzkaller-00205-gd786aba32000 #0 Not tainted [ 86.360308][ T5349] ------------------------------------------------------ [ 86.363414][ T5349] syz.0.0/5349 is trying to acquire lock: [ 86.365859][ T5349] ffff88803f180040 ((work_completion)(&(&conn->info_timer)->work)){+.+.}-{0:0}, at: __flush_work+0xd2/0xbc0 [ 86.370575][ T5349] [ 86.370575][ T5349] but task is already holding lock: [ 86.373729][ T5349] ffff88803f180338 (&conn->lock#2){+.+.}-{4:4}, at: l2cap_conn_del+0x70/0x680 [ 86.377657][ T5349] [ 86.377657][ T5349] which lock already depends on the new lock. [ 86.377657][ T5349] [ 86.382305][ T5349] [ 86.382305][ T5349] the existing dependency chain (in reverse order) is: [ 86.386180][ T5349] [ 86.386180][ T5349] -> #1 (&conn->lock#2){+.+.}-{4:4}: [ 86.389418][ T5349] lock_acquire+0x120/0x360 [ 86.391629][ T5349] __mutex_lock+0x182/0xe80 [ 86.393844][ T5349] l2cap_info_timeout+0x60/0xa0 [ 86.396206][ T5349] process_scheduled_works+0xae1/0x17b0 [ 86.399078][ T5349] worker_thread+0x8a0/0xda0 [ 86.401267][ T5349] kthread+0x70e/0x8a0 [ 86.403367][ T5349] ret_from_fork+0x3fc/0x770 [ 86.405760][ T5349] ret_from_fork_asm+0x1a/0x30 [ 86.408124][ T5349] [ 86.408124][ T5349] -> #0 ((work_completion)(&(&conn->info_timer)->work)){+.+.}-{0:0}: [ 86.412602][ T5349] validate_chain+0xb9b/0x2140 [ 86.414920][ T5349] __lock_acquire+0xab9/0xd20 [ 86.417225][ T5349] lock_acquire+0x120/0x360 [ 86.419418][ T5349] __flush_work+0x6b8/0xbc0 [ 86.421564][ T5349] __cancel_work_sync+0xbe/0x110 [ 86.423886][ T5349] l2cap_conn_del+0x4f0/0x680 [ 86.426136][ T5349] hci_conn_hash_flush+0x10a/0x230 [ 86.428607][ T5349] hci_dev_close_sync+0xaef/0x1330 [ 86.431144][ T5349] hci_dev_close+0x108/0x200 [ 86.433392][ T5349] sock_do_ioctl+0xd9/0x300 [ 86.435630][ T5349] sock_ioctl+0x576/0x790 [ 86.437754][ T5349] __se_sys_ioctl+0xf9/0x170 [ 86.440086][ T5349] do_syscall_64+0xfa/0x3b0 [ 86.442336][ T5349] entry_SYSCALL_64_after_hwframe+0x77/0x7f [ 86.445054][ T5349] [ 86.445054][ T5349] other info that might help us debug this: [ 86.445054][ T5349] [ 86.449554][ T5349] Possible unsafe locking scenario: [ 86.449554][ T5349] [ 86.452711][ T5349] CPU0 CPU1 [ 86.455031][ T5349] ---- ---- [ 86.457205][ T5349] lock(&conn->lock#2); [ 86.459334][ T5349] lock((work_completion)(&(&conn->info_timer)->work)); [ 86.464443][ T5349] lock(&conn->lock#2); [ 86.467590][ T5349] lock((work_completion)(&(&conn->info_timer)->work)); [ 86.470813][ T5349] [ 86.470813][ T5349] *** DEADLOCK *** [ 86.470813][ T5349] [ 86.474377][ T5349] 5 locks held by syz.0.0/5349: [ 86.476448][ T5349] #0: ffff888038efcdc0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_dev_close+0x100/0x200 [ 86.480554][ T5349] #1: ffff888038efc0b8 (&hdev->lock){+.+.}-{4:4}, at: hci_dev_close_sync+0x66a/0x1330 [ 86.484538][ T5349] #2: ffffffff8f685ac8 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_conn_hash_flush+0xa1/0x230 [ 86.488886][ T5349] #3: ffff88803f180338 (&conn->lock#2){+.+.}-{4:4}, at: l2cap_conn_del+0x70/0x680 [ 86.493046][ T5349] #4: ffffffff8e13f0e0 (rcu_read_lock){....}-{1:3}, at: __flush_work+0xd2/0xbc0 [ 86.497953][ T5349] [ 86.497953][ T5349] stack backtrace: [ 86.500563][ T5349] CPU: 0 UID: 0 PID: 5349 Comm: syz.0.0 Not tainted 6.16.0-rc6-syzkaller-00205-gd786aba32000 #0 PREEMPT(full) [ 86.500580][ T5349] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014 [ 86.500588][ T5349] Call Trace: [ 86.500595][ T5349] [ 86.500600][ T5349] dump_stack_lvl+0x189/0x250 [ 86.500619][ T5349] ? __pfx_dump_stack_lvl+0x10/0x10 [ 86.500631][ T5349] ? __pfx__printk+0x10/0x10 [ 86.500645][ T5349] ? print_lock_name+0xde/0x100 [ 86.500661][ T5349] print_circular_bug+0x2ee/0x310 [ 86.500677][ T5349] check_noncircular+0x134/0x160 [ 86.500693][ T5349] validate_chain+0xb9b/0x2140 [ 86.500705][ T5349] ? do_raw_spin_lock+0x121/0x290 [ 86.500716][ T5349] ? look_up_lock_class+0x74/0x170 [ 86.500723][ T5349] ? register_lock_class+0x51/0x320 [ 86.500730][ T5349] __lock_acquire+0xab9/0xd20 [ 86.500737][ T5349] ? __flush_work+0xd2/0xbc0 [ 86.500745][ T5349] lock_acquire+0x120/0x360 [ 86.500751][ T5349] ? __flush_work+0xd2/0xbc0 [ 86.500760][ T5349] ? _raw_spin_unlock_irq+0x23/0x50 [ 86.500770][ T5349] ? __flush_work+0xd2/0xbc0 [ 86.500779][ T5349] __flush_work+0x6b8/0xbc0 [ 86.500788][ T5349] ? __flush_work+0xd2/0xbc0 [ 86.500796][ T5349] ? __flush_work+0xd2/0xbc0 [ 86.500805][ T5349] ? __pfx___flush_work+0x10/0x10 [ 86.500813][ T5349] ? __pfx_wq_barrier_func+0x10/0x10 [ 86.500822][ T5349] ? __pfx___cancel_work+0x10/0x10 [ 86.500831][ T5349] ? hci_conn_drop+0x14d/0x280 [ 86.500843][ T5349] __cancel_work_sync+0xbe/0x110 [ 86.500851][ T5349] l2cap_conn_del+0x4f0/0x680 [ 86.500860][ T5349] ? __pfx_l2cap_disconn_cfm+0x10/0x10 [ 86.500868][ T5349] hci_conn_hash_flush+0x10a/0x230 [ 86.500877][ T5349] hci_dev_close_sync+0xaef/0x1330 [ 86.500886][ T5349] ? __pfx_hci_dev_close_sync+0x10/0x10 [ 86.500893][ T5349] ? do_raw_read_unlock+0x3d/0x80 [ 86.500902][ T5349] hci_dev_close+0x108/0x200 [ 86.500910][ T5349] sock_do_ioctl+0xd9/0x300 [ 86.500921][ T5349] ? __pfx_sock_do_ioctl+0x10/0x10 [ 86.500930][ T5349] ? __lock_acquire+0xab9/0xd20 [ 86.500942][ T5349] sock_ioctl+0x576/0x790 [ 86.500955][ T5349] ? __pfx_sock_ioctl+0x10/0x10 [ 86.500968][ T5349] ? __fget_files+0x2a/0x420 [ 86.500987][ T5349] ? __fget_files+0x3a0/0x420 [ 86.500997][ T5349] ? __fget_files+0x2a/0x420 [ 86.501006][ T5349] ? bpf_lsm_file_ioctl+0x9/0x20 [ 86.501014][ T5349] ? __pfx_sock_ioctl+0x10/0x10 [ 86.501024][ T5349] __se_sys_ioctl+0xf9/0x170 [ 86.501031][ T5349] do_syscall_64+0xfa/0x3b0 [ 86.501039][ T5349] ? lockdep_hardirqs_on+0x9c/0x150 [ 86.501045][ T5349] ? entry_SYSCALL_64_after_hwframe+0x77/0x7f [ 86.501051][ T5349] ? clear_bhb_loop+0x60/0xb0 [ 86.501058][ T5349] entry_SYSCALL_64_after_hwframe+0x77/0x7f [ 86.501065][ T5349] RIP: 0033:0x7f191bf8e9a9 [ 86.501073][ T5349] 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 [ 86.501079][ T5349] RSP: 002b:00007f191ce1c038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 [ 86.501086][ T5349] RAX: ffffffffffffffda RBX: 00007f191c1b5fa0 RCX: 00007f191bf8e9a9 [ 86.501091][ T5349] RDX: 0000000000000000 RSI: 00000000400448ca RDI: 0000000000000004 [ 86.501095][ T5349] RBP: 00007f191c010d69 R08: 0000000000000000 R09: 0000000000000000 [ 86.501099][ T5349] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 [ 86.501102][ T5349] R13: 0000000000000000 R14: 00007f191c1b5fa0 R15: 00007fffceb31a88 [ 86.501109][ T5349] [ 86.662270][ T5352] fido_id[5352]: Failed to open report descriptor at '/sys/devices/virtual/bluetooth/hci0/hci0:200/report_descriptor': No such file or directory [ 86.680715][ T9] cfg80211: failed to load regulatory.db [ 88.281411][ T4688] Bluetooth: hci0: command tx timeout [ 90.361381][ T4688] Bluetooth: hci0: command tx timeout [ 92.441138][ T4688] Bluetooth: hci0: command tx timeout