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, 0x9, 0x9, 0x1, 0x1, 'syz1\x00'}) r2 = syz_init_net_socket$bt_hci(0x1f, 0x3, 0x1) ioctl$sock_bt_hci(r2, 0x400448ca, 0x0) [ 85.486579][ T5299] Bluetooth: hci0: command tx timeout [ 85.633030][ T9] hid-multitouch 0005:0457:0009.0002: unknown main item tag 0x0 [ 85.666311][ T9] hid-multitouch 0005:0457:0009.0002: hidraw1: BLUETOOTH HID v0.09 Device [syz1] on aa:aa:aa:aa:aa:aa [ 85.695161][ T5321] [ 85.696318][ T5321] ====================================================== [ 85.699486][ T5321] WARNING: possible circular locking dependency detected [ 85.702627][ T5321] syzkaller #0 Not tainted [ 85.704617][ T5321] ------------------------------------------------------ [ 85.707919][ T5321] syz.0.0/5321 is trying to acquire lock: [ 85.710451][ T5321] ffff888012378040 ((work_completion)(&(&conn->info_timer)->work)){+.+.}-{0:0}, at: __flush_work+0x100/0xc50 [ 85.715643][ T5321] [ 85.715643][ T5321] but task is already holding lock: [ 85.718835][ T5321] ffff888012378338 (&conn->lock#2){+.+.}-{4:4}, at: l2cap_conn_del+0x7b/0x5b0 [ 85.722776][ T5321] [ 85.722776][ T5321] which lock already depends on the new lock. [ 85.722776][ T5321] [ 85.726896][ T5321] [ 85.726896][ T5321] the existing dependency chain (in reverse order) is: [ 85.730400][ T5321] [ 85.730400][ T5321] -> #1 (&conn->lock#2){+.+.}-{4:4}: [ 85.733431][ T5321] __mutex_lock+0x19f/0x1300 [ 85.735464][ T5321] l2cap_info_timeout+0x60/0xa0 [ 85.737676][ T5321] process_scheduled_works+0xaec/0x17a0 [ 85.740630][ T5321] worker_thread+0xda6/0x1360 [ 85.743239][ T5321] kthread+0x726/0x8b0 [ 85.745360][ T5321] ret_from_fork+0x51b/0xa40 [ 85.747709][ T5321] ret_from_fork_asm+0x1a/0x30 [ 85.750100][ T5321] [ 85.750100][ T5321] -> #0 ((work_completion)(&(&conn->info_timer)->work)){+.+.}-{0:0}: [ 85.754676][ T5321] __lock_acquire+0x15a5/0x2cf0 [ 85.757110][ T5321] lock_acquire+0x106/0x330 [ 85.759413][ T5321] __flush_work+0x700/0xc50 [ 85.761771][ T5321] __cancel_work_sync+0xbe/0x110 [ 85.764286][ T5321] l2cap_conn_del+0x402/0x5b0 [ 85.766544][ T5321] hci_conn_hash_flush+0x10d/0x260 [ 85.768947][ T5321] hci_dev_close_sync+0x821/0x10e0 [ 85.771437][ T5321] hci_dev_close+0x108/0x260 [ 85.773738][ T5321] sock_do_ioctl+0x101/0x320 [ 85.776025][ T5321] sock_ioctl+0x5c6/0x7f0 [ 85.778245][ T5321] __se_sys_ioctl+0xfc/0x170 [ 85.780374][ T5321] do_syscall_64+0xe2/0xf80 [ 85.782382][ T5321] entry_SYSCALL_64_after_hwframe+0x77/0x7f [ 85.784880][ T5321] [ 85.784880][ T5321] other info that might help us debug this: [ 85.784880][ T5321] [ 85.788970][ T5321] Possible unsafe locking scenario: [ 85.788970][ T5321] [ 85.792136][ T5321] CPU0 CPU1 [ 85.794541][ T5321] ---- ---- [ 85.796909][ T5321] lock(&conn->lock#2); [ 85.798812][ T5321] lock((work_completion)(&(&conn->info_timer)->work)); [ 85.802608][ T5321] lock(&conn->lock#2); [ 85.805241][ T5321] lock((work_completion)(&(&conn->info_timer)->work)); [ 85.808057][ T5321] [ 85.808057][ T5321] *** DEADLOCK *** [ 85.808057][ T5321] [ 85.811298][ T5321] 5 locks held by syz.0.0/5321: [ 85.813277][ T5321] #0: ffff8880126e4ec0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_dev_close+0x100/0x260 [ 85.817157][ T5321] #1: ffff8880126e40c0 (&hdev->lock){+.+.}-{4:4}, at: hci_dev_close_sync+0x640/0x10e0 [ 85.821427][ T5321] #2: ffffffff8fb3ad68 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_conn_hash_flush+0xa1/0x260 [ 85.825859][ T5321] #3: ffff888012378338 (&conn->lock#2){+.+.}-{4:4}, at: l2cap_conn_del+0x7b/0x5b0 [ 85.829873][ T5321] #4: ffffffff8e55a360 (rcu_read_lock){....}-{1:3}, at: __flush_work+0x100/0xc50 [ 85.834047][ T5321] [ 85.834047][ T5321] stack backtrace: [ 85.836633][ T5321] CPU: 0 UID: 0 PID: 5321 Comm: syz.0.0 Not tainted syzkaller #0 PREEMPT(full) [ 85.836647][ T5321] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014 [ 85.836654][ T5321] Call Trace: [ 85.836662][ T5321] [ 85.836668][ T5321] dump_stack_lvl+0xe8/0x150 [ 85.836688][ T5321] print_circular_bug+0x2e1/0x300 [ 85.836702][ T5321] check_noncircular+0x12e/0x150 [ 85.836714][ T5321] __lock_acquire+0x15a5/0x2cf0 [ 85.836732][ T5321] ? do_raw_spin_lock+0x12b/0x2f0 [ 85.836748][ T5321] ? __flush_work+0x100/0xc50 [ 85.836758][ T5321] lock_acquire+0x106/0x330 [ 85.836772][ T5321] ? __flush_work+0x100/0xc50 [ 85.836784][ T5321] ? __flush_work+0x100/0xc50 [ 85.836794][ T5321] __flush_work+0x700/0xc50 [ 85.836804][ T5321] ? __flush_work+0x100/0xc50 [ 85.836814][ T5321] ? __flush_work+0x100/0xc50 [ 85.836825][ T5321] ? __pfx___flush_work+0x10/0x10 [ 85.836836][ T5321] ? __pfx_wq_barrier_func+0x10/0x10 [ 85.836855][ T5321] ? __cancel_work_sync+0x5c/0x110 [ 85.836867][ T5321] __cancel_work_sync+0xbe/0x110 [ 85.836879][ T5321] l2cap_conn_del+0x402/0x5b0 [ 85.836899][ T5321] ? __pfx_l2cap_disconn_cfm+0x10/0x10 [ 85.836912][ T5321] hci_conn_hash_flush+0x10d/0x260 [ 85.836922][ T5321] hci_dev_close_sync+0x821/0x10e0 [ 85.836936][ T5321] ? __pfx_hci_dev_close_sync+0x10/0x10 [ 85.836946][ T5321] ? lockdep_hardirqs_on+0x7a/0x110 [ 85.836958][ T5321] ? enable_work+0x1fd/0x230 [ 85.836972][ T5321] hci_dev_close+0x108/0x260 [ 85.836984][ T5321] sock_do_ioctl+0x101/0x320 [ 85.837003][ T5321] ? __pfx_sock_do_ioctl+0x10/0x10 [ 85.837016][ T5321] ? do_futex+0x395/0x420 [ 85.837028][ T5321] sock_ioctl+0x5c6/0x7f0 [ 85.837037][ T5321] ? __pfx_sock_ioctl+0x10/0x10 [ 85.837045][ T5321] ? __fget_files+0x2a/0x420 [ 85.837053][ T5321] ? __fget_files+0x3a0/0x420 [ 85.837059][ T5321] ? __fget_files+0x2a/0x420 [ 85.837065][ T5321] ? bpf_lsm_file_ioctl+0x9/0x20 [ 85.837073][ T5321] ? __pfx_sock_ioctl+0x10/0x10 [ 85.837082][ T5321] __se_sys_ioctl+0xfc/0x170 [ 85.837095][ T5321] do_syscall_64+0xe2/0xf80 [ 85.837106][ T5321] ? entry_SYSCALL_64_after_hwframe+0x77/0x7f [ 85.837117][ T5321] ? trace_irq_disable+0x37/0x100 [ 85.837129][ T5321] ? clear_bhb_loop+0x60/0xb0 [ 85.837142][ T5321] entry_SYSCALL_64_after_hwframe+0x77/0x7f [ 85.837154][ T5321] RIP: 0033:0x7f936dd9aeb9 [ 85.837166][ 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 [ 85.837176][ T5321] RSP: 002b:00007f936ece9028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 [ 85.837190][ T5321] RAX: ffffffffffffffda RBX: 00007f936e015fa0 RCX: 00007f936dd9aeb9 [ 85.837199][ T5321] RDX: 0000000000000000 RSI: 00000000400448ca RDI: 0000000000000006 [ 85.837206][ T5321] RBP: 00007f936de08c1f R08: 0000000000000000 R09: 0000000000000000 [ 85.837213][ T5321] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 [ 85.837221][ T5321] R13: 00007f936e016038 R14: 00007f936e015fa0 R15: 00007fff8a5cf4d8 [ 85.837234][ T5321] [ 85.985241][ T5330] fido_id[5330]: Failed to open report descriptor at '/sys/devices/virtual/bluetooth/hci0/hci0:200/report_descriptor': No such file or directory [ 87.496212][ T4667] Bluetooth: hci0: command tx timeout [ 89.576498][ T4667] Bluetooth: hci0: command tx timeout [ 91.656105][ T4667] Bluetooth: hci0: command tx timeout [ 91.896389][ T787] cfg80211: failed to load regulatory.db