program: r0 = socket$inet_mptcp(0x2, 0x1, 0x106) ioctl$sock_inet_SIOCSIFFLAGS(r0, 0x8914, &(0x7f0000000000)={'lo\x00', 0x100}) 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'}) r3 = syz_init_net_socket$bt_hci(0x1f, 0x3, 0x1) ioctl$sock_bt_hci(r3, 0x400448ca, 0x0) syz_emit_ethernet(0x7a, &(0x7f0000000040)={@local, @multicast, @void, {@ipv6={0x86dd, @gre_packet={0x5, 0x6, "d15cdc", 0x44, 0x2f, 0x1, @local, @private0, {[], {{0x0, 0x0, 0x1, 0x1}, {0x1, 0x0, 0x0, 0x1}, {0x1, 0x0, 0x0, 0x1}, {0x8, 0x88be, 0x0, {{0x0, 0x1, 0x0, 0x1, 0x1, 0x0, 0x1, 0x3}, 0x1, {0x5}}}, {0x8, 0x22eb, 0x1, {{0x5, 0x2, 0x5, 0x2, 0x0, 0x3, 0x7, 0x6}, 0x2, {0x7, 0x3, 0x2, 0x2, 0x1, 0x1, 0x2, 0x1, 0x1}}}, {0x8, 0x6558, 0x4}}}}}}}, 0x0) socket$inet_mptcp(0x2, 0x1, 0x106) (async) ioctl$sock_inet_SIOCSIFFLAGS(r0, 0x8914, &(0x7f0000000000)={'lo\x00', 0x100}) (async) syz_init_net_socket$bt_l2cap(0x1f, 0x2, 0x0) (async) connect$bt_l2cap(r1, &(0x7f0000000080)={0x1f, 0x0, @fixed={'\xaa\xaa\xaa\xaa\xaa', 0x10}, 0x7ff}, 0xe) (async) syz_init_net_socket$bt_hidp(0x1f, 0x3, 0x6) (async) ioctl$sock_bt_hidp_HIDPCONNADD(r2, 0x400448c8, &(0x7f0000000280)={r1, r1, 0xc, 0x1, &(0x7f0000000340)='\x00', 0x9, 0x1, 0x457, 0x9, 0x9, 0x1, 0x1, 'syz1\x00'}) (async) syz_init_net_socket$bt_hci(0x1f, 0x3, 0x1) (async) ioctl$sock_bt_hci(r3, 0x400448ca, 0x0) (async) syz_emit_ethernet(0x7a, &(0x7f0000000040)={@local, @multicast, @void, {@ipv6={0x86dd, @gre_packet={0x5, 0x6, "d15cdc", 0x44, 0x2f, 0x1, @local, @private0, {[], {{0x0, 0x0, 0x1, 0x1}, {0x1, 0x0, 0x0, 0x1}, {0x1, 0x0, 0x0, 0x1}, {0x8, 0x88be, 0x0, {{0x0, 0x1, 0x0, 0x1, 0x1, 0x0, 0x1, 0x3}, 0x1, {0x5}}}, {0x8, 0x22eb, 0x1, {{0x5, 0x2, 0x5, 0x2, 0x0, 0x3, 0x7, 0x6}, 0x2, {0x7, 0x3, 0x2, 0x2, 0x1, 0x1, 0x2, 0x1, 0x1}}}, {0x8, 0x6558, 0x4}}}}}}}, 0x0) (async) [ 85.145116][ T5295] Bluetooth: hci0: command tx timeout [ 85.375660][ T5318] lo: entered promiscuous mode [ 85.404307][ T9] hid-multitouch 0005:0457:0009.0002: unknown main item tag 0x0 [ 85.419467][ T9] hid-multitouch 0005:0457:0009.0002: hidraw1: BLUETOOTH HID v0.09 Device [syz1] on aa:aa:aa:aa:aa:aa [ 85.452681][ T5318] [ 85.453791][ T5318] ====================================================== [ 85.456748][ T5318] WARNING: possible circular locking dependency detected [ 85.459728][ T5318] syzkaller #0 Not tainted [ 85.461811][ T5318] ------------------------------------------------------ [ 85.465076][ T5318] syz.0.0/5318 is trying to acquire lock: [ 85.467581][ T5318] ffff88804140c840 ((work_completion)(&(&conn->info_timer)->work)){+.+.}-{0:0}, at: __flush_work+0x100/0xc50 [ 85.472968][ T5318] [ 85.472968][ T5318] but task is already holding lock: [ 85.477044][ T5318] ffff88804140caf8 (&conn->lock#2){+.+.}-{4:4}, at: l2cap_conn_del+0x7b/0x5c0 [ 85.481131][ T5318] [ 85.481131][ T5318] which lock already depends on the new lock. [ 85.481131][ T5318] [ 85.485841][ T5318] [ 85.485841][ T5318] the existing dependency chain (in reverse order) is: [ 85.489725][ T5318] [ 85.489725][ T5318] -> #1 (&conn->lock#2){+.+.}-{4:4}: [ 85.493198][ T5318] __mutex_lock+0x19f/0x1300 [ 85.495978][ T5318] l2cap_info_timeout+0x60/0xa0 [ 85.498895][ T5318] process_scheduled_works+0xb02/0x1830 [ 85.501933][ T5318] worker_thread+0xa50/0xfc0 [ 85.504389][ T5318] kthread+0x388/0x470 [ 85.506408][ T5318] ret_from_fork+0x51e/0xb90 [ 85.508579][ T5318] ret_from_fork_asm+0x1a/0x30 [ 85.510907][ T5318] [ 85.510907][ T5318] -> #0 ((work_completion)(&(&conn->info_timer)->work)){+.+.}-{0:0}: [ 85.515308][ T5318] __lock_acquire+0x15a5/0x2cf0 [ 85.517591][ T5318] lock_acquire+0xf0/0x2e0 [ 85.519814][ T5318] __flush_work+0x700/0xc50 [ 85.522025][ T5318] __cancel_work_sync+0xbe/0x110 [ 85.524491][ T5318] l2cap_conn_del+0x40f/0x5c0 [ 85.526883][ T5318] hci_conn_hash_flush+0x10d/0x260 [ 85.529426][ T5318] hci_dev_close_sync+0x821/0x10e0 [ 85.531938][ T5318] hci_dev_close+0x108/0x260 [ 85.534286][ T5318] sock_do_ioctl+0x101/0x320 [ 85.537086][ T5318] sock_ioctl+0x5c6/0x7f0 [ 85.539250][ T5318] __se_sys_ioctl+0xfc/0x170 [ 85.541599][ T5318] do_syscall_64+0x14d/0xf80 [ 85.543855][ T5318] entry_SYSCALL_64_after_hwframe+0x77/0x7f [ 85.546650][ T5318] [ 85.546650][ T5318] other info that might help us debug this: [ 85.546650][ T5318] [ 85.551222][ T5318] Possible unsafe locking scenario: [ 85.551222][ T5318] [ 85.554211][ T5318] CPU0 CPU1 [ 85.556898][ T5318] ---- ---- [ 85.560024][ T5318] lock(&conn->lock#2); [ 85.562024][ T5318] lock((work_completion)(&(&conn->info_timer)->work)); [ 85.566123][ T5318] lock(&conn->lock#2); [ 85.569093][ T5318] lock((work_completion)(&(&conn->info_timer)->work)); [ 85.572085][ T5318] [ 85.572085][ T5318] *** DEADLOCK *** [ 85.572085][ T5318] [ 85.575687][ T5318] 5 locks held by syz.0.0/5318: [ 85.577846][ T5318] #0: ffff888012a98ec0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_dev_close+0x100/0x260 [ 85.581846][ T5318] #1: ffff888012a980c0 (&hdev->lock){+.+.}-{4:4}, at: hci_dev_close_sync+0x640/0x10e0 [ 85.586263][ T5318] #2: ffffffff8fd587a8 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_conn_hash_flush+0xa1/0x260 [ 85.590684][ T5318] #3: ffff88804140caf8 (&conn->lock#2){+.+.}-{4:4}, at: l2cap_conn_del+0x7b/0x5c0 [ 85.594834][ T5318] #4: ffffffff8e7603e0 (rcu_read_lock){....}-{1:3}, at: __flush_work+0x100/0xc50 [ 85.598749][ T5318] [ 85.598749][ T5318] stack backtrace: [ 85.601262][ T5318] CPU: 0 UID: 0 PID: 5318 Comm: syz.0.0 Not tainted syzkaller #0 PREEMPT(full) [ 85.601301][ T5318] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014 [ 85.601308][ T5318] Call Trace: [ 85.601317][ T5318] [ 85.601353][ T5318] dump_stack_lvl+0xe8/0x150 [ 85.601372][ T5318] print_circular_bug+0x2e1/0x300 [ 85.601390][ T5318] check_noncircular+0x12e/0x150 [ 85.601404][ T5318] __lock_acquire+0x15a5/0x2cf0 [ 85.601417][ T5318] ? do_raw_spin_lock+0x12b/0x2f0 [ 85.601430][ T5318] ? do_raw_spin_unlock+0x4d/0x210 [ 85.601440][ T5318] lock_acquire+0xf0/0x2e0 [ 85.601451][ T5318] ? __flush_work+0x100/0xc50 [ 85.601467][ T5318] ? __flush_work+0x100/0xc50 [ 85.601479][ T5318] __flush_work+0x700/0xc50 [ 85.601492][ T5318] ? __flush_work+0x100/0xc50 [ 85.601503][ T5318] ? __flush_work+0x100/0xc50 [ 85.601515][ T5318] ? __pfx___flush_work+0x10/0x10 [ 85.601528][ T5318] ? __pfx_wq_barrier_func+0x10/0x10 [ 85.601545][ T5318] ? __cancel_work_sync+0x5c/0x110 [ 85.601557][ T5318] __cancel_work_sync+0xbe/0x110 [ 85.601571][ T5318] l2cap_conn_del+0x40f/0x5c0 [ 85.601587][ T5318] ? __pfx_l2cap_disconn_cfm+0x10/0x10 [ 85.601600][ T5318] hci_conn_hash_flush+0x10d/0x260 [ 85.601614][ T5318] hci_dev_close_sync+0x821/0x10e0 [ 85.601629][ T5318] ? __pfx_hci_dev_close_sync+0x10/0x10 [ 85.601640][ T5318] ? lockdep_hardirqs_on+0x7a/0x110 [ 85.601656][ T5318] ? enable_work+0x1fd/0x230 [ 85.601670][ T5318] hci_dev_close+0x108/0x260 [ 85.601684][ T5318] sock_do_ioctl+0x101/0x320 [ 85.601696][ T5318] ? __pfx_sock_do_ioctl+0x10/0x10 [ 85.601705][ T5318] ? do_futex+0x395/0x420 [ 85.601719][ T5318] sock_ioctl+0x5c6/0x7f0 [ 85.601729][ T5318] ? __pfx_sock_ioctl+0x10/0x10 [ 85.601738][ T5318] ? __fget_files+0x2a/0x420 [ 85.601750][ T5318] ? __fget_files+0x3a0/0x420 [ 85.601760][ T5318] ? __fget_files+0x2a/0x420 [ 85.601770][ T5318] ? bpf_lsm_file_ioctl+0x9/0x20 [ 85.601779][ T5318] ? __pfx_sock_ioctl+0x10/0x10 [ 85.601789][ T5318] __se_sys_ioctl+0xfc/0x170 [ 85.601804][ T5318] do_syscall_64+0x14d/0xf80 [ 85.601814][ T5318] ? trace_irq_disable+0x3b/0x150 [ 85.601828][ T5318] ? entry_SYSCALL_64_after_hwframe+0x77/0x7f [ 85.601838][ T5318] ? clear_bhb_loop+0x40/0x90 [ 85.601850][ T5318] entry_SYSCALL_64_after_hwframe+0x77/0x7f [ 85.601860][ T5318] RIP: 0033:0x7fca9019bf79 [ 85.601872][ T5318] 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 [ 85.601880][ T5318] RSP: 002b:00007fca910c3028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 [ 85.601892][ T5318] RAX: ffffffffffffffda RBX: 00007fca90415fa0 RCX: 00007fca9019bf79 [ 85.601899][ T5318] RDX: 0000000000000000 RSI: 00000000400448ca RDI: 0000000000000007 [ 85.601905][ T5318] RBP: 00007fca902327e0 R08: 0000000000000000 R09: 0000000000000000 [ 85.601910][ T5318] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 [ 85.601916][ T5318] R13: 00007fca90416038 R14: 00007fca90415fa0 R15: 00007fffad9f2658 [ 85.601926][ T5318] [ 85.831860][ T5326] fido_id[5326]: Failed to open report descriptor at '/sys/devices/virtual/bluetooth/hci0/hci0:200/report_descriptor': No such file or directory [ 87.206773][ T4662] Bluetooth: hci0: command tx timeout [ 89.287110][ T4662] Bluetooth: hci0: command tx timeout [ 91.367028][ T4662] Bluetooth: hci0: command tx timeout [ 92.013192][ T1229] cfg80211: failed to load regulatory.db