program: r0 = socket(0x10, 0x803, 0x0) sendto(r0, &(0x7f00000000c0)="120000001200e7ef007b00000000000000a1", 0x12, 0x0, 0x0, 0x0) r1 = socket$inet_sctp(0x2, 0x1, 0x84) bind$inet(r1, &(0x7f0000000000)={0x2, 0x4e22, @local}, 0x10) sendto$inet(r1, &(0x7f00000000c0)='}', 0x1, 0x0, &(0x7f00000001c0)={0x2, 0x4e22, @local}, 0x10) r2 = socket$inet_sctp(0x2, 0x1, 0x84) getsockopt$inet_sctp_SCTP_MAX_BURST(r2, 0x84, 0x7b, &(0x7f0000000000)=@assoc_value={0x0}, &(0x7f0000000080)=0x8) getsockopt$inet_sctp_SCTP_GET_LOCAL_ADDRS(r1, 0x84, 0x6d, &(0x7f0000000440)={r3, 0x10, "dcbcb6828825df9975c16ed60386d68a"}, &(0x7f0000000100)=0x18) socket$inet(0x2, 0x6, 0x5) r4 = syz_open_dev$tty1(0xc, 0x4, 0x1) r5 = socket$inet6_sctp(0xa, 0x1, 0x84) r6 = socket$nl_netfilter(0x10, 0x3, 0xc) sendmsg$NFT_BATCH(r6, &(0x7f00000000c0)={0x0, 0x0, &(0x7f0000000040)={&(0x7f0000000200)={{0x14}, [@NFT_MSG_NEWTABLE={0x20, 0x0, 0xa, 0x301, 0x0, 0x0, {0x1, 0x0, 0xfffd}, [@NFTA_TABLE_NAME={0x9, 0x1, 'syz0\x00'}]}, @NFT_MSG_NEWCHAIN={0x2c, 0x3, 0xa, 0x201, 0x0, 0x0, {0x1}, [@NFTA_CHAIN_NAME={0x9, 0x3, 'syz2\x00'}, @NFTA_CHAIN_TABLE={0x9, 0x1, 'syz0\x00'}]}, @NFT_MSG_NEWRULE={0x44, 0x6, 0xa, 0x401, 0x0, 0x0, {0x1}, [@NFTA_RULE_CHAIN_ID={0x8}, @NFTA_RULE_TABLE={0x9, 0x1, 'syz0\x00'}, @NFTA_RULE_EXPRESSIONS={0x1c, 0x4, 0x0, 0x1, [{0x18, 0x1, 0x0, 0x1, @synproxy={{0xd}, @val={0x4}}}]}]}], {0x14}}, 0xb8}}, 0x0) setsockopt$SO_ATTACH_FILTER(r5, 0x1, 0x1a, &(0x7f0000000040)={0x1, &(0x7f0000000340)=[{0x6, 0x0, 0x0, 0x67b}]}, 0x10) bind$inet6(r5, &(0x7f00004b8fe4)={0xa, 0x4e23, 0x0, @empty}, 0x1c) sendto$inet6(r5, &(0x7f0000847fff)='X', 0x1, 0x50, &(0x7f000005ffe4)={0xa, 0x4e23, 0x2, @loopback, 0xfffffffd}, 0x1c) setsockopt$inet_sctp6_SCTP_PEER_ADDR_PARAMS(r5, 0x84, 0x9, &(0x7f0000000a00)={0x0, @in6={{0xa, 0x4e23, 0x0, @loopback}}, 0x0, 0x0, 0x0, 0x0, 0x4}, 0x9c) ioctl$KDSETLED(r4, 0x4b32, 0x6) r7 = syz_init_net_socket$bt_l2cap(0x1f, 0x2, 0x0) connect$bt_l2cap(r7, &(0x7f0000000080)={0x1f, 0x0, @fixed={'\xaa\xaa\xaa\xaa\xaa', 0x10}, 0x7ff}, 0xe) r8 = syz_init_net_socket$bt_hidp(0x1f, 0x3, 0x6) ioctl$sock_bt_hidp_HIDPCONNADD(r8, 0x400448c8, &(0x7f00000000c0)={r7, r7, 0x206, 0x0, 0x0, 0x2, 0x72, 0x1, 0x3, 0x7, 0x0, 0x8, 'syz1\x00'}) r9 = syz_init_net_socket$bt_hci(0x1f, 0x3, 0x1) ioctl$HCIINQUIRY(r9, 0x400448ca, 0x0) recvmmsg(r0, &(0x7f00000037c0)=[{{0x0, 0x0, &(0x7f00000006c0)=[{&(0x7f0000000000)=""/102, 0x66}, {&(0x7f0000000280)=""/76, 0x4c}, {&(0x7f0000000fc0)=""/4096, 0x1000}, {&(0x7f0000000400)=""/92, 0x5c}, {&(0x7f0000000980)=""/73, 0x49}, {&(0x7f0000000200)=""/77, 0x4d}, {&(0x7f00000007c0)=""/154, 0x9a}, {&(0x7f0000001fc0)=""/4099, 0x1003}, {&(0x7f0000000080)=""/7, 0x7}], 0x9}}], 0x1, 0x0, 0x0) [ 85.392570][ T47] Bluetooth: hci0: command tx timeout [ 85.538684][ T5343] input: Bluetooth HID Boot Protocol Device as /devices/virtual/bluetooth/hci0/hci0:200/input5 [ 85.834176][ T5348] [ 85.835266][ T5348] ====================================================== [ 85.838262][ T5348] WARNING: possible circular locking dependency detected [ 85.840976][ T5348] syzkaller #0 Not tainted [ 85.842768][ T5348] ------------------------------------------------------ [ 85.845525][ T5348] syz.0.0/5348 is trying to acquire lock: [ 85.847612][ T5348] ffff888041f3b840 ((work_completion)(&(&conn->info_timer)->work)){+.+.}-{0:0}, at: __flush_work+0x100/0xc50 [ 85.852147][ T5348] [ 85.852147][ T5348] but task is already holding lock: [ 85.854934][ T5348] ffff888041f3bb38 (&conn->lock#2){+.+.}-{4:4}, at: l2cap_conn_del+0x7b/0x5b0 [ 85.858626][ T5348] [ 85.858626][ T5348] which lock already depends on the new lock. [ 85.858626][ T5348] [ 85.863025][ T5348] [ 85.863025][ T5348] the existing dependency chain (in reverse order) is: [ 85.866792][ T5348] [ 85.866792][ T5348] -> #1 (&conn->lock#2){+.+.}-{4:4}: [ 85.869788][ T5348] __mutex_lock+0x19f/0x1300 [ 85.871890][ T5348] l2cap_info_timeout+0x60/0xa0 [ 85.874091][ T5348] process_scheduled_works+0xaec/0x17a0 [ 85.876881][ T5348] worker_thread+0x89f/0xd90 [ 85.879245][ T5348] kthread+0x726/0x8b0 [ 85.881337][ T5348] ret_from_fork+0x51b/0xa40 [ 85.883705][ T5348] ret_from_fork_asm+0x1a/0x30 [ 85.885901][ T5348] [ 85.885901][ T5348] -> #0 ((work_completion)(&(&conn->info_timer)->work)){+.+.}-{0:0}: [ 85.889745][ T5348] __lock_acquire+0x15a5/0x2cf0 [ 85.891972][ T5348] lock_acquire+0x106/0x330 [ 85.894179][ T5348] __flush_work+0x700/0xc50 [ 85.896514][ T5348] __cancel_work_sync+0xbe/0x110 [ 85.899031][ T5348] l2cap_conn_del+0x402/0x5b0 [ 85.901881][ T5348] hci_conn_hash_flush+0x10d/0x260 [ 85.905221][ T5348] hci_dev_close_sync+0x821/0x10e0 [ 85.908407][ T5348] hci_dev_close+0x108/0x260 [ 85.911333][ T5348] sock_do_ioctl+0x101/0x320 [ 85.914206][ T5348] sock_ioctl+0x5c6/0x7f0 [ 85.917152][ T5348] __se_sys_ioctl+0xfc/0x170 [ 85.920140][ T5348] do_syscall_64+0xe2/0xf80 [ 85.923140][ T5348] entry_SYSCALL_64_after_hwframe+0x77/0x7f [ 85.926005][ T5348] [ 85.926005][ T5348] other info that might help us debug this: [ 85.926005][ T5348] [ 85.930446][ T5348] Possible unsafe locking scenario: [ 85.930446][ T5348] [ 85.933818][ T5348] CPU0 CPU1 [ 85.936460][ T5348] ---- ---- [ 85.938756][ T5348] lock(&conn->lock#2); [ 85.940514][ T5348] lock((work_completion)(&(&conn->info_timer)->work)); [ 85.944631][ T5348] lock(&conn->lock#2); [ 85.947795][ T5348] lock((work_completion)(&(&conn->info_timer)->work)); [ 85.950988][ T5348] [ 85.950988][ T5348] *** DEADLOCK *** [ 85.950988][ T5348] [ 85.954649][ T5348] 5 locks held by syz.0.0/5348: [ 85.956958][ T5348] #0: ffff88803fca0ec0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_dev_close+0x100/0x260 [ 85.961259][ T5348] #1: ffff88803fca00c0 (&hdev->lock){+.+.}-{4:4}, at: hci_dev_close_sync+0x640/0x10e0 [ 85.965436][ T5348] #2: ffffffff8f936fc8 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_conn_hash_flush+0xa1/0x260 [ 85.969648][ T5348] #3: ffff888041f3bb38 (&conn->lock#2){+.+.}-{4:4}, at: l2cap_conn_del+0x7b/0x5b0 [ 85.973687][ T5348] #4: ffffffff8e35a360 (rcu_read_lock){....}-{1:3}, at: __flush_work+0x100/0xc50 [ 85.977625][ T5348] [ 85.977625][ T5348] stack backtrace: [ 85.980101][ T5348] CPU: 0 UID: 0 PID: 5348 Comm: syz.0.0 Not tainted syzkaller #0 PREEMPT(full) [ 85.980113][ T5348] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014 [ 85.980119][ T5348] Call Trace: [ 85.980124][ T5348] [ 85.980129][ T5348] dump_stack_lvl+0xe8/0x150 [ 85.980143][ T5348] print_circular_bug+0x2e1/0x300 [ 85.980157][ T5348] check_noncircular+0x12e/0x150 [ 85.980172][ T5348] __lock_acquire+0x15a5/0x2cf0 [ 85.980184][ T5348] ? do_raw_spin_lock+0x12b/0x2f0 [ 85.980201][ T5348] ? __flush_work+0x100/0xc50 [ 85.980214][ T5348] lock_acquire+0x106/0x330 [ 85.980223][ T5348] ? __flush_work+0x100/0xc50 [ 85.980237][ T5348] ? __flush_work+0x100/0xc50 [ 85.980249][ T5348] __flush_work+0x700/0xc50 [ 85.980260][ T5348] ? __flush_work+0x100/0xc50 [ 85.980272][ T5348] ? __flush_work+0x100/0xc50 [ 85.980285][ T5348] ? __pfx___flush_work+0x10/0x10 [ 85.980297][ T5348] ? __pfx_wq_barrier_func+0x10/0x10 [ 85.980313][ T5348] ? __cancel_work_sync+0x5c/0x110 [ 85.980325][ T5348] __cancel_work_sync+0xbe/0x110 [ 85.980339][ T5348] l2cap_conn_del+0x402/0x5b0 [ 85.980355][ T5348] ? __pfx_l2cap_disconn_cfm+0x10/0x10 [ 85.980368][ T5348] hci_conn_hash_flush+0x10d/0x260 [ 85.980385][ T5348] hci_dev_close_sync+0x821/0x10e0 [ 85.980398][ T5348] ? __pfx_hci_dev_close_sync+0x10/0x10 [ 85.980409][ T5348] ? lockdep_hardirqs_on+0x7a/0x110 [ 85.980424][ T5348] ? enable_work+0x1e9/0x220 [ 85.980440][ T5348] hci_dev_close+0x108/0x260 [ 85.980453][ T5348] sock_do_ioctl+0x101/0x320 [ 85.980464][ T5348] ? __pfx_sock_do_ioctl+0x10/0x10 [ 85.980474][ T5348] ? do_futex+0x395/0x420 [ 85.980489][ T5348] sock_ioctl+0x5c6/0x7f0 [ 85.980499][ T5348] ? __pfx_sock_ioctl+0x10/0x10 [ 85.980509][ T5348] ? __fget_files+0x2a/0x420 [ 85.980521][ T5348] ? __fget_files+0x3a0/0x420 [ 85.980533][ T5348] ? __fget_files+0x2a/0x420 [ 85.980546][ T5348] ? bpf_lsm_file_ioctl+0x9/0x20 [ 85.980557][ T5348] ? __pfx_sock_ioctl+0x10/0x10 [ 85.980567][ T5348] __se_sys_ioctl+0xfc/0x170 [ 85.980585][ T5348] do_syscall_64+0xe2/0xf80 [ 85.980599][ T5348] ? entry_SYSCALL_64_after_hwframe+0x77/0x7f [ 85.980608][ T5348] ? trace_irq_disable+0x37/0x100 [ 85.980625][ T5348] ? clear_bhb_loop+0x60/0xb0 [ 85.980637][ T5348] entry_SYSCALL_64_after_hwframe+0x77/0x7f [ 85.980651][ T5348] RIP: 0033:0x7f947f59acb9 [ 85.980663][ T5348] 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 [ 85.980673][ T5348] RSP: 002b:00007f94804e8028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 [ 85.980688][ T5348] RAX: ffffffffffffffda RBX: 00007f947f816180 RCX: 00007f947f59acb9 [ 85.980696][ T5348] RDX: 0000000000000000 RSI: 00000000400448ca RDI: 000000000000000c [ 85.980704][ T5348] RBP: 00007f947f608bf7 R08: 0000000000000000 R09: 0000000000000000 [ 85.980711][ T5348] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 [ 85.980718][ T5348] R13: 00007f947f816218 R14: 00007f947f816180 R15: 00007ffc600ea6c8 [ 85.980731][ T5348] [ 87.397430][ T47] Bluetooth: hci0: command tx timeout [ 89.478085][ T47] Bluetooth: hci0: command tx timeout [ 91.558147][ T47] Bluetooth: hci0: command tx timeout [ 91.564821][ T789] cfg80211: failed to load regulatory.db