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$bt_hci(0x1f, 0x3, 0x1) ioctl$HCIINQUIRY(r2, 0x400448ca, 0x0) [ 85.062687][ T45] Bluetooth: hci0: command tx timeout [ 85.214580][ T4714] hid-multitouch 0005:0457:0009.0002: unknown main item tag 0x0 [ 85.255554][ T4714] hid-multitouch 0005:0457:0009.0002: hidraw1: BLUETOOTH HID v0.09 Device [syz1] on aa:aa:aa:aa:aa:aa [ 85.339241][ T5324] [ 85.340432][ T5324] ====================================================== [ 85.343966][ T5324] WARNING: possible circular locking dependency detected [ 85.347496][ T5324] syzkaller #0 Not tainted [ 85.349575][ T5324] ------------------------------------------------------ [ 85.352602][ T5324] syz.0.0/5324 is trying to acquire lock: [ 85.354833][ T5324] ffff888042a13040 ((work_completion)(&(&conn->info_timer)->work)){+.+.}-{0:0}, at: __flush_work+0x100/0xc50 [ 85.361496][ T5324] [ 85.361496][ T5324] but task is already holding lock: [ 85.364672][ T5324] ffff888042a132f8 (&conn->lock#2){+.+.}-{4:4}, at: l2cap_conn_del+0x7b/0x5c0 [ 85.368442][ T5324] [ 85.368442][ T5324] which lock already depends on the new lock. [ 85.368442][ T5324] [ 85.373193][ T5324] [ 85.373193][ T5324] the existing dependency chain (in reverse order) is: [ 85.377706][ T5324] [ 85.377706][ T5324] -> #1 (&conn->lock#2){+.+.}-{4:4}: [ 85.381664][ T5324] __mutex_lock+0x19f/0x1300 [ 85.384053][ T5324] l2cap_info_timeout+0x60/0xa0 [ 85.386809][ T5324] process_scheduled_works+0xb6e/0x18c0 [ 85.389870][ T5324] worker_thread+0xa53/0xfc0 [ 85.392182][ T5324] kthread+0x388/0x470 [ 85.394213][ T5324] ret_from_fork+0x51e/0xb90 [ 85.396590][ T5324] ret_from_fork_asm+0x1a/0x30 [ 85.399433][ T5324] [ 85.399433][ T5324] -> #0 ((work_completion)(&(&conn->info_timer)->work)){+.+.}-{0:0}: [ 85.403842][ T5324] __lock_acquire+0x15a5/0x2cf0 [ 85.406079][ T5324] lock_acquire+0xf0/0x2e0 [ 85.408458][ T5324] __flush_work+0x700/0xc50 [ 85.411235][ T5324] __cancel_work_sync+0xbe/0x110 [ 85.413827][ T5324] l2cap_conn_del+0x40f/0x5c0 [ 85.416052][ T5324] hci_conn_hash_flush+0x10d/0x260 [ 85.419074][ T5324] hci_dev_close_sync+0x821/0x10e0 [ 85.421841][ T5324] hci_dev_close+0x108/0x260 [ 85.424355][ T5324] sock_do_ioctl+0x101/0x320 [ 85.427277][ T5324] sock_ioctl+0x5c6/0x7f0 [ 85.429851][ T5324] __se_sys_ioctl+0xfc/0x170 [ 85.432305][ T5324] do_syscall_64+0x14d/0xf80 [ 85.434534][ T5324] entry_SYSCALL_64_after_hwframe+0x77/0x7f [ 85.437448][ T5324] [ 85.437448][ T5324] other info that might help us debug this: [ 85.437448][ T5324] [ 85.442810][ T5324] Possible unsafe locking scenario: [ 85.442810][ T5324] [ 85.446320][ T5324] CPU0 CPU1 [ 85.448701][ T5324] ---- ---- [ 85.451097][ T5324] lock(&conn->lock#2); [ 85.452975][ T5324] lock((work_completion)(&(&conn->info_timer)->work)); [ 85.457050][ T5324] lock(&conn->lock#2); [ 85.459886][ T5324] lock((work_completion)(&(&conn->info_timer)->work)); [ 85.463669][ T5324] [ 85.463669][ T5324] *** DEADLOCK *** [ 85.463669][ T5324] [ 85.467309][ T5324] 5 locks held by syz.0.0/5324: [ 85.469262][ T5324] #0: ffff888034d30ec0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_dev_close+0x100/0x260 [ 85.473073][ T5324] #1: ffff888034d300c0 (&hdev->lock){+.+.}-{4:4}, at: hci_dev_close_sync+0x640/0x10e0 [ 85.477482][ T5324] #2: ffffffff8fd5c868 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_conn_hash_flush+0xa1/0x260 [ 85.482122][ T5324] #3: ffff888042a132f8 (&conn->lock#2){+.+.}-{4:4}, at: l2cap_conn_del+0x7b/0x5c0 [ 85.486253][ T5324] #4: ffffffff8e75e520 (rcu_read_lock){....}-{1:3}, at: __flush_work+0x100/0xc50 [ 85.490424][ T5324] [ 85.490424][ T5324] stack backtrace: [ 85.493107][ T5324] CPU: 0 UID: 0 PID: 5324 Comm: syz.0.0 Not tainted syzkaller #0 PREEMPT(full) [ 85.493128][ T5324] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014 [ 85.493139][ T5324] Call Trace: [ 85.493149][ T5324] [ 85.493158][ T5324] dump_stack_lvl+0xe8/0x150 [ 85.493184][ T5324] print_circular_bug+0x2e1/0x300 [ 85.493208][ T5324] check_noncircular+0x12e/0x150 [ 85.493229][ T5324] __lock_acquire+0x15a5/0x2cf0 [ 85.493244][ T5324] ? do_raw_spin_lock+0x12b/0x2f0 [ 85.493257][ T5324] ? do_raw_spin_unlock+0x4d/0x210 [ 85.493267][ T5324] lock_acquire+0xf0/0x2e0 [ 85.493281][ T5324] ? __flush_work+0x100/0xc50 [ 85.493299][ T5324] ? __flush_work+0x100/0xc50 [ 85.493315][ T5324] __flush_work+0x700/0xc50 [ 85.493331][ T5324] ? __flush_work+0x100/0xc50 [ 85.493345][ T5324] ? __flush_work+0x100/0xc50 [ 85.493362][ T5324] ? __pfx___flush_work+0x10/0x10 [ 85.493378][ T5324] ? __pfx_wq_barrier_func+0x10/0x10 [ 85.493396][ T5324] ? __cancel_work_sync+0x5c/0x110 [ 85.493414][ T5324] __cancel_work_sync+0xbe/0x110 [ 85.493429][ T5324] l2cap_conn_del+0x40f/0x5c0 [ 85.493445][ T5324] ? __pfx_l2cap_disconn_cfm+0x10/0x10 [ 85.493462][ T5324] hci_conn_hash_flush+0x10d/0x260 [ 85.493480][ T5324] hci_dev_close_sync+0x821/0x10e0 [ 85.493496][ T5324] ? __pfx_hci_dev_close_sync+0x10/0x10 [ 85.493510][ T5324] ? lockdep_hardirqs_on+0x7a/0x110 [ 85.493521][ T5324] ? enable_work+0x1fd/0x230 [ 85.493540][ T5324] hci_dev_close+0x108/0x260 [ 85.493556][ T5324] sock_do_ioctl+0x101/0x320 [ 85.493571][ T5324] ? __pfx_sock_do_ioctl+0x10/0x10 [ 85.493582][ T5324] ? do_futex+0x395/0x420 [ 85.493599][ T5324] sock_ioctl+0x5c6/0x7f0 [ 85.493613][ T5324] ? __pfx_sock_ioctl+0x10/0x10 [ 85.493624][ T5324] ? __fget_files+0x2a/0x420 [ 85.493640][ T5324] ? __fget_files+0x3a0/0x420 [ 85.493656][ T5324] ? __fget_files+0x2a/0x420 [ 85.493671][ T5324] ? bpf_lsm_file_ioctl+0x9/0x20 [ 85.493687][ T5324] ? __pfx_sock_ioctl+0x10/0x10 [ 85.493698][ T5324] __se_sys_ioctl+0xfc/0x170 [ 85.493709][ T5324] do_syscall_64+0x14d/0xf80 [ 85.493720][ T5324] ? trace_irq_disable+0x3b/0x150 [ 85.493739][ T5324] ? entry_SYSCALL_64_after_hwframe+0x77/0x7f [ 85.493763][ T5324] ? clear_bhb_loop+0x40/0x90 [ 85.493778][ T5324] entry_SYSCALL_64_after_hwframe+0x77/0x7f [ 85.493792][ T5324] RIP: 0033:0x7f9b1879c799 [ 85.493806][ T5324] 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 [ 85.493816][ T5324] RSP: 002b:00007f9b19673fe8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 [ 85.493830][ T5324] RAX: ffffffffffffffda RBX: 00007f9b18a15fa0 RCX: 00007f9b1879c799 [ 85.493840][ T5324] RDX: 0000000000000000 RSI: 00000000400448ca RDI: 0000000000000006 [ 85.493848][ T5324] RBP: 00007f9b18832c99 R08: 0000000000000000 R09: 0000000000000000 [ 85.493855][ T5324] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 [ 85.493864][ T5324] R13: 00007f9b18a16038 R14: 00007f9b18a15fa0 R15: 00007ffe8c94de08 [ 85.493877][ T5324] [ 85.727980][ T5330] fido_id[5330]: Failed to open report descriptor at '/sys/devices/virtual/bluetooth/hci0/hci0:200/report_descriptor': No such file or directory [ 87.072984][ T45] Bluetooth: hci0: command tx timeout [ 89.152856][ T45] Bluetooth: hci0: command tx timeout [ 91.232782][ T45] Bluetooth: hci0: command tx timeout [ 91.962925][ T53] cfg80211: failed to load regulatory.db