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$bt_hidp(0x1f, 0x3, 0x6) r2 = socket$nl_netfilter(0x10, 0x3, 0xc) sendmsg$IPSET_CMD_CREATE(r2, &(0x7f0000000040)={0x0, 0x0, &(0x7f00000044c0)={&(0x7f0000000200)={0x4c, 0x2, 0x6, 0x101, 0x0, 0x0, {}, [@IPSET_ATTR_FAMILY={0x5, 0x5, 0x2}, @IPSET_ATTR_PROTOCOL={0x5}, @IPSET_ATTR_REVISION={0x5, 0x4, 0x3}, @IPSET_ATTR_SETNAME={0x9, 0x2, 'syz1\x00'}, @IPSET_ATTR_TYPENAME={0x11, 0x3, 'hash:net,net\x00'}]}, 0x4c}, 0x1, 0x0, 0x0, 0x4040000}, 0x800) r3 = socket$nl_netfilter(0x10, 0x3, 0xc) sendmsg$IPSET_CMD_ADD(r3, &(0x7f0000000000)={0x0, 0x0, &(0x7f0000000240)={&(0x7f0000000580)={0x50, 0x9, 0x6, 0x201, 0x0, 0x0, {0x3}, [@IPSET_ATTR_SETNAME={0x9, 0x2, 'syz1\x00'}, @IPSET_ATTR_PROTOCOL={0x5}, @IPSET_ATTR_DATA={0x28, 0x7, 0x0, 0x1, [@IPSET_ATTR_IP={0xc, 0x1, 0x0, 0x1, @IPSET_ATTR_IPADDR_IPV4={0x8, 0x1, 0x1, 0x0, @dev={0xac, 0x14, 0x14, 0x3b}}}, @IPSET_ATTR_IP2={0xc, 0x14, 0x0, 0x1, @IPSET_ATTR_IPADDR_IPV4={0x8, 0x1, 0x1, 0x0, @remote}}, @IPSET_ATTR_IP_TO={0xc, 0x2, 0x0, 0x1, @IPSET_ATTR_IPADDR_IPV4={0x20, 0x1, 0x1, 0x0, @loopback}}]}]}, 0x50}, 0x1, 0x0, 0x0, 0xd24f4d5758621d46}, 0x0) ioctl$sock_bt_hidp_HIDPCONNADD(r1, 0x400448c8, &(0x7f0000000280)={r0, r0, 0xc, 0x0, 0x0, 0x9, 0x1, 0x1, 0x9, 0x9, 0x1, 0x1, 'syz1\x00'}) r4 = syz_init_net_socket$bt_hci(0x1f, 0x3, 0x1) ioctl$HCIINQUIRY(r4, 0x400448ca, 0x0) [ 85.267455][ T5297] Bluetooth: hci0: command tx timeout [ 85.339960][ T5320] netlink: 8 bytes leftover after parsing attributes in process `syz.0.0'. [ 85.385195][ T5320] input: Bluetooth HID Boot Protocol Device as /devices/virtual/bluetooth/hci0/hci0:200/input5 [ 85.448035][ T5321] [ 85.449229][ T5321] ====================================================== [ 85.452245][ T5321] WARNING: possible circular locking dependency detected [ 85.455233][ T5321] syzkaller #0 Not tainted [ 85.457227][ T5321] ------------------------------------------------------ [ 85.460325][ T5321] syz.0.0/5321 is trying to acquire lock: [ 85.462991][ T5321] ffff888044d0f840 ((work_completion)(&(&conn->info_timer)->work)){+.+.}-{0:0}, at: __flush_work+0x100/0xc50 [ 85.468205][ T5321] [ 85.468205][ T5321] but task is already holding lock: [ 85.471498][ T5321] ffff888044d0faf8 (&conn->lock#2){+.+.}-{4:4}, at: l2cap_conn_del+0x7b/0x5c0 [ 85.475471][ T5321] [ 85.475471][ T5321] which lock already depends on the new lock. [ 85.475471][ T5321] [ 85.480272][ T5321] [ 85.480272][ T5321] the existing dependency chain (in reverse order) is: [ 85.484123][ T5321] [ 85.484123][ T5321] -> #1 (&conn->lock#2){+.+.}-{4:4}: [ 85.487393][ T5321] __mutex_lock+0x19f/0x1300 [ 85.489821][ T5321] l2cap_info_timeout+0x60/0xa0 [ 85.492310][ T5321] process_scheduled_works+0xb02/0x1830 [ 85.495032][ T5321] worker_thread+0xa50/0xfc0 [ 85.497407][ T5321] kthread+0x388/0x470 [ 85.499560][ T5321] ret_from_fork+0x51e/0xb90 [ 85.501945][ T5321] ret_from_fork_asm+0x1a/0x30 [ 85.504285][ T5321] [ 85.504285][ T5321] -> #0 ((work_completion)(&(&conn->info_timer)->work)){+.+.}-{0:0}: [ 85.508678][ T5321] __lock_acquire+0x15a5/0x2cf0 [ 85.511122][ T5321] lock_acquire+0xf0/0x2e0 [ 85.513286][ T5321] __flush_work+0x700/0xc50 [ 85.515507][ T5321] __cancel_work_sync+0xbe/0x110 [ 85.517890][ T5321] l2cap_conn_del+0x40f/0x5c0 [ 85.520102][ T5321] hci_conn_hash_flush+0x10d/0x260 [ 85.522676][ T5321] hci_dev_close_sync+0x821/0x10e0 [ 85.525208][ T5321] hci_dev_close+0x108/0x260 [ 85.527537][ T5321] sock_do_ioctl+0x101/0x320 [ 85.529922][ T5321] sock_ioctl+0x5c6/0x7f0 [ 85.532100][ T5321] __se_sys_ioctl+0xfc/0x170 [ 85.534405][ T5321] do_syscall_64+0x14d/0xf80 [ 85.536974][ T5321] entry_SYSCALL_64_after_hwframe+0x77/0x7f [ 85.539742][ T5321] [ 85.539742][ T5321] other info that might help us debug this: [ 85.539742][ T5321] [ 85.544181][ T5321] Possible unsafe locking scenario: [ 85.544181][ T5321] [ 85.547366][ T5321] CPU0 CPU1 [ 85.549720][ T5321] ---- ---- [ 85.552269][ T5321] lock(&conn->lock#2); [ 85.554198][ T5321] lock((work_completion)(&(&conn->info_timer)->work)); [ 85.558452][ T5321] lock(&conn->lock#2); [ 85.561476][ T5321] lock((work_completion)(&(&conn->info_timer)->work)); [ 85.564560][ T5321] [ 85.564560][ T5321] *** DEADLOCK *** [ 85.564560][ T5321] [ 85.568257][ T5321] 5 locks held by syz.0.0/5321: [ 85.570409][ T5321] #0: ffff888042ce0ec0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_dev_close+0x100/0x260 [ 85.574476][ T5321] #1: ffff888042ce00c0 (&hdev->lock){+.+.}-{4:4}, at: hci_dev_close_sync+0x640/0x10e0 [ 85.578529][ T5321] #2: ffffffff8fd5b868 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_conn_hash_flush+0xa1/0x260 [ 85.583169][ T5321] #3: ffff888044d0faf8 (&conn->lock#2){+.+.}-{4:4}, at: l2cap_conn_del+0x7b/0x5c0 [ 85.587891][ T5321] #4: ffffffff8e7602e0 (rcu_read_lock){....}-{1:3}, at: __flush_work+0x100/0xc50 [ 85.592259][ T5321] [ 85.592259][ T5321] stack backtrace: [ 85.595067][ T5321] CPU: 0 UID: 0 PID: 5321 Comm: syz.0.0 Not tainted syzkaller #0 PREEMPT(full) [ 85.595085][ T5321] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014 [ 85.595093][ T5321] Call Trace: [ 85.595101][ T5321] [ 85.595106][ T5321] dump_stack_lvl+0xe8/0x150 [ 85.595127][ T5321] print_circular_bug+0x2e1/0x300 [ 85.595147][ T5321] check_noncircular+0x12e/0x150 [ 85.595168][ T5321] __lock_acquire+0x15a5/0x2cf0 [ 85.595183][ T5321] ? do_raw_spin_lock+0x12b/0x2f0 [ 85.595197][ T5321] ? do_raw_spin_unlock+0x4d/0x210 [ 85.595208][ T5321] lock_acquire+0xf0/0x2e0 [ 85.595222][ T5321] ? __flush_work+0x100/0xc50 [ 85.595240][ T5321] ? __flush_work+0x100/0xc50 [ 85.595254][ T5321] __flush_work+0x700/0xc50 [ 85.595269][ T5321] ? __flush_work+0x100/0xc50 [ 85.595284][ T5321] ? __flush_work+0x100/0xc50 [ 85.595299][ T5321] ? __pfx___flush_work+0x10/0x10 [ 85.595314][ T5321] ? __pfx_wq_barrier_func+0x10/0x10 [ 85.595331][ T5321] ? __cancel_work_sync+0x5c/0x110 [ 85.595347][ T5321] __cancel_work_sync+0xbe/0x110 [ 85.595363][ T5321] l2cap_conn_del+0x40f/0x5c0 [ 85.595380][ T5321] ? __pfx_l2cap_disconn_cfm+0x10/0x10 [ 85.595393][ T5321] hci_conn_hash_flush+0x10d/0x260 [ 85.595409][ T5321] hci_dev_close_sync+0x821/0x10e0 [ 85.595423][ T5321] ? __pfx_hci_dev_close_sync+0x10/0x10 [ 85.595434][ T5321] ? lockdep_hardirqs_on+0x7a/0x110 [ 85.595450][ T5321] ? enable_work+0x1fd/0x230 [ 85.595468][ T5321] hci_dev_close+0x108/0x260 [ 85.595481][ T5321] sock_do_ioctl+0x101/0x320 [ 85.595499][ T5321] ? __pfx_sock_do_ioctl+0x10/0x10 [ 85.595516][ T5321] ? do_futex+0x395/0x420 [ 85.595534][ T5321] sock_ioctl+0x5c6/0x7f0 [ 85.595550][ T5321] ? __pfx_sock_ioctl+0x10/0x10 [ 85.595565][ T5321] ? __fget_files+0x2a/0x420 [ 85.595579][ T5321] ? __fget_files+0x3a0/0x420 [ 85.595589][ T5321] ? __fget_files+0x2a/0x420 [ 85.595602][ T5321] ? bpf_lsm_file_ioctl+0x9/0x20 [ 85.595612][ T5321] ? __pfx_sock_ioctl+0x10/0x10 [ 85.595626][ T5321] __se_sys_ioctl+0xfc/0x170 [ 85.595645][ T5321] do_syscall_64+0x14d/0xf80 [ 85.595663][ T5321] ? trace_irq_disable+0x3b/0x150 [ 85.595680][ T5321] ? entry_SYSCALL_64_after_hwframe+0x77/0x7f [ 85.595693][ T5321] ? clear_bhb_loop+0x40/0x90 [ 85.595706][ T5321] entry_SYSCALL_64_after_hwframe+0x77/0x7f [ 85.595717][ T5321] RIP: 0033:0x7f683cd9c799 [ 85.595729][ 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 [ 85.595738][ T5321] RSP: 002b:00007f683dbae028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 [ 85.595751][ T5321] RAX: ffffffffffffffda RBX: 00007f683d016090 RCX: 00007f683cd9c799 [ 85.595760][ T5321] RDX: 0000000000000000 RSI: 00000000400448ca RDI: 0000000000000008 [ 85.595767][ T5321] RBP: 00007f683ce32bd9 R08: 0000000000000000 R09: 0000000000000000 [ 85.595774][ T5321] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 [ 85.595781][ T5321] R13: 00007f683d016128 R14: 00007f683d016090 R15: 00007ffee862a318 [ 85.595793][ T5321] [ 87.290223][ T4663] Bluetooth: hci0: command tx timeout [ 89.367481][ T4663] Bluetooth: hci0: command tx timeout [ 91.447302][ T4663] Bluetooth: hci0: command tx timeout [ 91.931930][ T10] cfg80211: failed to load regulatory.db