program: r0 = openat$sysctl(0xffffffffffffff9c, &(0x7f0000000340)='/proc/sys/net/ipv4/tcp_mtu_probing\x00', 0x1, 0x0) pwritev2(r0, &(0x7f00000001c0)=[{&(0x7f0000000040)='4', 0x1}], 0x1, 0x0, 0x0, 0x0) r1 = socket$nl_route(0x10, 0x3, 0x0) sendmsg$nl_route(r1, &(0x7f0000000140)={0x0, 0x0, &(0x7f0000000080)={&(0x7f0000000380)=ANY=[@ANYBLOB="300000001000010800"/20, @ANYRES32=0x0, @ANYBLOB="0000000000000000080004004400000008001b"], 0x30}}, 0x0) r2 = socket$inet_tcp(0x2, 0x1, 0x0) bind$inet(r2, &(0x7f0000000000)={0x2, 0x4e20, @multicast2}, 0x10) connect$inet(r2, &(0x7f0000000080)={0x2, 0x4e20, @loopback}, 0x10) sendmmsg$inet(r2, &(0x7f0000000740)=[{{0x0, 0x0, &(0x7f00000000c0)=[{&(0x7f0000003ac0)="bb", 0x1}, {&(0x7f00000004c0)="63da115df2fe0a0e1cbac9a5ed9c01b3d83109b6444383a7fa8868814b3f3b82259da5284293edbfaf97dcc7db70e4fb41430f1d082f60964cb7a7ec574a918f476b24617fd8c40c861055f337bed87e71daed0d81537df1315e8f3e41e82c981f12adb843193ca0f7ef8e38aa703d1f8a4aa9a9da8dfa41cc4795002344b3", 0x7f}, {&(0x7f0000000440)="82bad21d1d93f16c57b07f5cacf44e06f64236f3f394ef4ce8fb3576fec5deb12fca98ba28b742fb381ced933ea4fbbc89a1b3127a", 0x35}], 0x3}}, {{0x0, 0x0, &(0x7f0000004200)=[{&(0x7f00000001c0)="5a93f8b2", 0x4}], 0x1}}, {{0x0, 0x0, &(0x7f0000000100)=[{&(0x7f00000002c0)='\x00\x00X', 0x3}], 0x1}}], 0x3, 0x60cd894) r3 = syz_init_net_socket$bt_l2cap(0x1f, 0x2, 0x0) connect$bt_l2cap(r3, &(0x7f0000000080)={0x1f, 0x0, @fixed={'\xaa\xaa\xaa\xaa\xaa', 0x10}, 0x7ff}, 0xe) r4 = syz_init_net_socket$bt_hidp(0x1f, 0x3, 0x6) ioctl$sock_bt_hidp_HIDPCONNADD(r4, 0x400448c8, &(0x7f0000000280)={r3, r3, 0xc, 0x1, &(0x7f0000000340)='\x00', 0x9, 0x1, 0x457, 0x9, 0x9, 0x1, 0x1, 'syz1\x00'}) r5 = syz_init_net_socket$bt_hci(0x1f, 0x3, 0x1) ioctl$HCIINQUIRY(r5, 0x400448ca, 0x0) [ 85.340869][ T4665] Bluetooth: hci0: command tx timeout [ 85.472537][ T5324] hid-multitouch 0005:0457:0009.0002: unknown main item tag 0x0 [ 85.503563][ T5324] hid-multitouch 0005:0457:0009.0002: hidraw1: BLUETOOTH HID v0.09 Device [syz1] on aa:aa:aa:aa:aa:aa [ 85.571720][ T5326] [ 85.572871][ T5326] ====================================================== [ 85.575998][ T5326] WARNING: possible circular locking dependency detected [ 85.578974][ T5326] syzkaller #0 Not tainted [ 85.580847][ T5326] ------------------------------------------------------ [ 85.583761][ T5326] syz.0.0/5326 is trying to acquire lock: [ 85.586282][ T5326] ffff88803a03a840 ((work_completion)(&(&conn->info_timer)->work)){+.+.}-{0:0}, at: __flush_work+0x100/0xc50 [ 85.590837][ T5326] [ 85.590837][ T5326] but task is already holding lock: [ 85.593985][ T5326] ffff88803a03aaf8 (&conn->lock#2){+.+.}-{4:4}, at: l2cap_conn_del+0x7b/0x5c0 [ 85.597895][ T5326] [ 85.597895][ T5326] which lock already depends on the new lock. [ 85.597895][ T5326] [ 85.602292][ T5326] [ 85.602292][ T5326] the existing dependency chain (in reverse order) is: [ 85.606211][ T5326] [ 85.606211][ T5326] -> #1 (&conn->lock#2){+.+.}-{4:4}: [ 85.609409][ T5326] __mutex_lock+0x19f/0x1300 [ 85.611572][ T5326] l2cap_info_timeout+0x60/0xa0 [ 85.613651][ T5326] process_scheduled_works+0xb02/0x1830 [ 85.616214][ T5326] worker_thread+0xa50/0xfc0 [ 85.618421][ T5326] kthread+0x388/0x470 [ 85.620522][ T5326] ret_from_fork+0x51e/0xb90 [ 85.622775][ T5326] ret_from_fork_asm+0x1a/0x30 [ 85.624914][ T5326] [ 85.624914][ T5326] -> #0 ((work_completion)(&(&conn->info_timer)->work)){+.+.}-{0:0}: [ 85.629131][ T5326] __lock_acquire+0x15a5/0x2cf0 [ 85.631247][ T5326] lock_acquire+0xf0/0x2e0 [ 85.633437][ T5326] __flush_work+0x700/0xc50 [ 85.635557][ T5326] __cancel_work_sync+0xbe/0x110 [ 85.637827][ T5326] l2cap_conn_del+0x40f/0x5c0 [ 85.639978][ T5326] hci_conn_hash_flush+0x10d/0x260 [ 85.642305][ T5326] hci_dev_close_sync+0x821/0x10e0 [ 85.644645][ T5326] hci_dev_close+0x108/0x260 [ 85.646839][ T5326] sock_do_ioctl+0x101/0x320 [ 85.648999][ T5326] sock_ioctl+0x5c6/0x7f0 [ 85.651037][ T5326] __se_sys_ioctl+0xfc/0x170 [ 85.653242][ T5326] do_syscall_64+0x14d/0xf80 [ 85.655560][ T5326] entry_SYSCALL_64_after_hwframe+0x77/0x7f [ 85.658405][ T5326] [ 85.658405][ T5326] other info that might help us debug this: [ 85.658405][ T5326] [ 85.662757][ T5326] Possible unsafe locking scenario: [ 85.662757][ T5326] [ 85.665966][ T5326] CPU0 CPU1 [ 85.668334][ T5326] ---- ---- [ 85.670623][ T5326] lock(&conn->lock#2); [ 85.672366][ T5326] lock((work_completion)(&(&conn->info_timer)->work)); [ 85.676036][ T5326] lock(&conn->lock#2); [ 85.678594][ T5326] lock((work_completion)(&(&conn->info_timer)->work)); [ 85.681420][ T5326] [ 85.681420][ T5326] *** DEADLOCK *** [ 85.681420][ T5326] [ 85.684577][ T5326] 5 locks held by syz.0.0/5326: [ 85.686451][ T5326] #0: ffff8880378ccec0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_dev_close+0x100/0x260 [ 85.690488][ T5326] #1: ffff8880378cc0c0 (&hdev->lock){+.+.}-{4:4}, at: hci_dev_close_sync+0x640/0x10e0 [ 85.694722][ T5326] #2: ffffffff8fd5aea8 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_conn_hash_flush+0xa1/0x260 [ 85.699555][ T5326] #3: ffff88803a03aaf8 (&conn->lock#2){+.+.}-{4:4}, at: l2cap_conn_del+0x7b/0x5c0 [ 85.703634][ T5326] #4: ffffffff8e7602e0 (rcu_read_lock){....}-{1:3}, at: __flush_work+0x100/0xc50 [ 85.707758][ T5326] [ 85.707758][ T5326] stack backtrace: [ 85.710327][ T5326] CPU: 0 UID: 0 PID: 5326 Comm: syz.0.0 Not tainted syzkaller #0 PREEMPT(full) [ 85.710344][ T5326] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014 [ 85.710353][ T5326] Call Trace: [ 85.710363][ T5326] [ 85.710369][ T5326] dump_stack_lvl+0xe8/0x150 [ 85.710386][ T5326] print_circular_bug+0x2e1/0x300 [ 85.710402][ T5326] check_noncircular+0x12e/0x150 [ 85.710421][ T5326] __lock_acquire+0x15a5/0x2cf0 [ 85.710435][ T5326] ? do_raw_spin_lock+0x12b/0x2f0 [ 85.710448][ T5326] ? do_raw_spin_unlock+0x4d/0x210 [ 85.710459][ T5326] lock_acquire+0xf0/0x2e0 [ 85.710469][ T5326] ? __flush_work+0x100/0xc50 [ 85.710483][ T5326] ? __flush_work+0x100/0xc50 [ 85.710495][ T5326] __flush_work+0x700/0xc50 [ 85.710509][ T5326] ? __flush_work+0x100/0xc50 [ 85.710522][ T5326] ? __flush_work+0x100/0xc50 [ 85.710536][ T5326] ? __pfx___flush_work+0x10/0x10 [ 85.710550][ T5326] ? __pfx_wq_barrier_func+0x10/0x10 [ 85.710601][ T5326] ? __cancel_work_sync+0x5c/0x110 [ 85.710617][ T5326] __cancel_work_sync+0xbe/0x110 [ 85.710632][ T5326] l2cap_conn_del+0x40f/0x5c0 [ 85.710647][ T5326] ? __pfx_l2cap_disconn_cfm+0x10/0x10 [ 85.710659][ T5326] hci_conn_hash_flush+0x10d/0x260 [ 85.710675][ T5326] hci_dev_close_sync+0x821/0x10e0 [ 85.710689][ T5326] ? __pfx_hci_dev_close_sync+0x10/0x10 [ 85.710699][ T5326] ? lockdep_hardirqs_on+0x7a/0x110 [ 85.710718][ T5326] ? enable_work+0x1fd/0x230 [ 85.710736][ T5326] hci_dev_close+0x108/0x260 [ 85.710747][ T5326] sock_do_ioctl+0x101/0x320 [ 85.710768][ T5326] ? __pfx_sock_do_ioctl+0x10/0x10 [ 85.710782][ T5326] ? do_futex+0x395/0x420 [ 85.710796][ T5326] sock_ioctl+0x5c6/0x7f0 [ 85.710809][ T5326] ? __pfx_sock_ioctl+0x10/0x10 [ 85.710823][ T5326] ? __fget_files+0x2a/0x420 [ 85.710833][ T5326] ? __fget_files+0x3a0/0x420 [ 85.710844][ T5326] ? __fget_files+0x2a/0x420 [ 85.710856][ T5326] ? bpf_lsm_file_ioctl+0x9/0x20 [ 85.710866][ T5326] ? __pfx_sock_ioctl+0x10/0x10 [ 85.710880][ T5326] __se_sys_ioctl+0xfc/0x170 [ 85.710895][ T5326] do_syscall_64+0x14d/0xf80 [ 85.710905][ T5326] ? trace_irq_disable+0x3b/0x150 [ 85.710914][ T5326] ? entry_SYSCALL_64_after_hwframe+0x77/0x7f [ 85.710921][ T5326] ? clear_bhb_loop+0x40/0x90 [ 85.710927][ T5326] entry_SYSCALL_64_after_hwframe+0x77/0x7f [ 85.710934][ T5326] RIP: 0033:0x7f2b08b9c629 [ 85.710942][ T5326] 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 [ 85.710948][ T5326] RSP: 002b:00007f2b09b27028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 [ 85.710956][ T5326] RAX: ffffffffffffffda RBX: 00007f2b08e15fa0 RCX: 00007f2b08b9c629 [ 85.710963][ T5326] RDX: 0000000000000000 RSI: 00000000400448ca RDI: 0000000000000009 [ 85.710969][ T5326] RBP: 00007f2b08c32b39 R08: 0000000000000000 R09: 0000000000000000 [ 85.710974][ T5326] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 [ 85.710980][ T5326] R13: 00007f2b08e16038 R14: 00007f2b08e15fa0 R15: 00007fffecb700a8 [ 85.710989][ T5326] [ 85.947840][ T5329] fido_id[5329]: Failed to open report descriptor at '/sys/devices/virtual/bluetooth/hci0/hci0:200/report_descriptor': No such file or directory [ 87.390657][ T5301] Bluetooth: hci0: command tx timeout [ 89.471482][ T5301] Bluetooth: hci0: command tx timeout [ 91.550455][ T5301] Bluetooth: hci0: command tx timeout [ 92.031413][ T1105] cfg80211: failed to load regulatory.db