================================
WARNING: inconsistent lock state
4.20.0 #166 Not tainted
--------------------------------
inconsistent {IN-SOFTIRQ-W} -> {SOFTIRQ-ON-W} usage.
syz-executor3/24498 [HC0[0]:SC0[0]:HE1:SE1] takes:
0000000014b5b1eb (slock-AF_NETROM){+.?.}, at: spin_lock include/linux/spinlock.h:329 [inline]
0000000014b5b1eb (slock-AF_NETROM){+.?.}, at: nr_find_socket+0x113/0x160 net/netrom/af_netrom.c:177
{IN-SOFTIRQ-W} state was registered at:
  lock_acquire+0x1ed/0x520 kernel/locking/lockdep.c:3844
  __raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline]
  _raw_spin_lock+0x2d/0x40 kernel/locking/spinlock.c:144
  spin_lock include/linux/spinlock.h:329 [inline]
  nr_find_listener net/netrom/af_netrom.c:156 [inline]
  nr_rx_frame+0x5f8/0x1db0 net/netrom/af_netrom.c:955
  nr_loopback_timer+0x79/0x160 net/netrom/nr_loopback.c:62
  call_timer_fn+0x272/0x920 kernel/time/timer.c:1326
  expire_timers kernel/time/timer.c:1363 [inline]
  __run_timers+0x7e5/0xc70 kernel/time/timer.c:1682
  run_timer_softirq+0x52/0xb0 kernel/time/timer.c:1695
  __do_softirq+0x30c/0xb2e kernel/softirq.c:292
  do_softirq_own_stack+0x2a/0x40 arch/x86/entry/entry_64.S:1027
  do_softirq.part.13+0x126/0x160 kernel/softirq.c:337
  do_softirq kernel/softirq.c:329 [inline]
  __local_bh_enable_ip+0x21d/0x260 kernel/softirq.c:189
  local_bh_enable include/linux/bottom_half.h:32 [inline]
  get_next_corpse net/netfilter/nf_conntrack_core.c:1892 [inline]
  nf_ct_iterate_cleanup+0x295/0x5c0 net/netfilter/nf_conntrack_core.c:1915
  nf_ct_iterate_cleanup_net+0x237/0x2d0 net/netfilter/nf_conntrack_core.c:2000
  masq_device_event+0xcf/0x100 net/ipv4/netfilter/nf_nat_masquerade_ipv4.c:100
  notifier_call_chain+0x17e/0x380 kernel/notifier.c:93
  __raw_notifier_call_chain kernel/notifier.c:394 [inline]
  raw_notifier_call_chain+0x2d/0x40 kernel/notifier.c:401
  call_netdevice_notifiers_info+0x3f/0x90 net/core/dev.c:1733
  call_netdevice_notifiers net/core/dev.c:1751 [inline]
  __dev_notify_flags+0x29b/0x480 net/core/dev.c:7547
  dev_change_flags+0xfd/0x150 net/core/dev.c:7581
  dev_ifsioc+0x7d6/0xa80 net/core/dev_ioctl.c:237
  dev_ioctl+0x1b5/0xcc0 net/core/dev_ioctl.c:488
  sock_do_ioctl+0x1f6/0x420 net/socket.c:973
  sock_ioctl+0x313/0x690 net/socket.c:1074
  vfs_ioctl fs/ioctl.c:46 [inline]
  file_ioctl fs/ioctl.c:509 [inline]
  do_vfs_ioctl+0x1de/0x1790 fs/ioctl.c:696
  ksys_ioctl+0xa9/0xd0 fs/ioctl.c:713
  __do_sys_ioctl fs/ioctl.c:720 [inline]
  __se_sys_ioctl fs/ioctl.c:718 [inline]
  __x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:718
  do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290
  entry_SYSCALL_64_after_hwframe+0x49/0xbe
irq event stamp: 1668
hardirqs last  enabled at (1665): [<ffffffff8149f9d0>] __local_bh_enable_ip+0x160/0x260 kernel/softirq.c:194
hardirqs last disabled at (1667): [<ffffffff8149f990>] __local_bh_enable_ip+0x120/0x260 kernel/softirq.c:171
softirqs last  enabled at (1668): [<ffffffff86f8bd68>] spin_unlock_bh include/linux/spinlock.h:374 [inline]
softirqs last  enabled at (1668): [<ffffffff86f8bd68>] nr_find_socket+0x128/0x160 net/netrom/af_netrom.c:183
softirqs last disabled at (1666): [<ffffffff86f8bc64>] spin_lock_bh include/linux/spinlock.h:334 [inline]
softirqs last disabled at (1666): [<ffffffff86f8bc64>] nr_find_socket+0x24/0x160 net/netrom/af_netrom.c:172

other info that might help us debug this:
 Possible unsafe locking scenario:

       CPU0
       ----
  lock(slock-AF_NETROM);
  <Interrupt>
    lock(slock-AF_NETROM);

 *** DEADLOCK ***

1 lock held by syz-executor3/24498:
 #0: 0000000014b5b1eb (slock-AF_NETROM){+.?.}, at: spin_lock include/linux/spinlock.h:329 [inline]
 #0: 0000000014b5b1eb (slock-AF_NETROM){+.?.}, at: nr_find_socket+0x113/0x160 net/netrom/af_netrom.c:177

stack backtrace:
CPU: 1 PID: 24498 Comm: syz-executor3 Not tainted 4.20.0 #166
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x1d3/0x2c6 lib/dump_stack.c:113
 print_usage_bug.cold.59+0x320/0x41a kernel/locking/lockdep.c:2472
 valid_state kernel/locking/lockdep.c:2485 [inline]
 mark_lock_irq kernel/locking/lockdep.c:2679 [inline]
 mark_lock+0x1114/0x1cc0 kernel/locking/lockdep.c:3059
 mark_held_locks+0xc7/0x130 kernel/locking/lockdep.c:2737
 __trace_hardirqs_on_caller kernel/locking/lockdep.c:2766 [inline]
 lockdep_hardirqs_on+0x421/0x5c0 kernel/locking/lockdep.c:2811
 trace_hardirqs_on+0xbd/0x310 kernel/trace/trace_preemptirq.c:30
 __local_bh_enable_ip+0x160/0x260 kernel/softirq.c:194
 __raw_spin_unlock_bh include/linux/spinlock_api_smp.h:176 [inline]
 _raw_spin_unlock_bh+0x30/0x40 kernel/locking/spinlock.c:200
 spin_unlock_bh include/linux/spinlock.h:374 [inline]
 nr_find_socket+0x128/0x160 net/netrom/af_netrom.c:183
 nr_find_next_circuit+0x71/0x90 net/netrom/af_netrom.c:225
 nr_connect+0x6cb/0x1350 net/netrom/af_netrom.c:704
 __sys_connect+0x37d/0x4c0 net/socket.c:1664
 __do_sys_connect net/socket.c:1675 [inline]
 __se_sys_connect net/socket.c:1672 [inline]
 __x64_sys_connect+0x73/0xb0 net/socket.c:1672
 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x457759
Code: fd b3 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 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 0f 83 cb b3 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007fbd80ae4c78 EFLAGS: 00000246 ORIG_RAX: 000000000000002a
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000457759
RDX: 0000000000000048 RSI: 0000000020000000 RDI: 0000000000000006
RBP: 000000000073bf00 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007fbd80ae56d4
R13: 00000000004bddbb R14: 00000000004cdee8 R15: 00000000ffffffff
kobject: 'loop4' (0000000000dcb711): kobject_uevent_env
kobject: 'loop4' (0000000000dcb711): fill_kobj_path: path = '/devices/virtual/block/loop4'
kobject: 'loop2' (00000000320db566): kobject_uevent_env
kobject: 'loop2' (00000000320db566): fill_kobj_path: path = '/devices/virtual/block/loop2'
kobject: 'loop5' (000000000d8855a4): kobject_uevent_env
kobject: 'loop5' (000000000d8855a4): fill_kobj_path: path = '/devices/virtual/block/loop5'
kobject: 'loop1' (000000006ac05693): kobject_uevent_env
kobject: 'loop1' (000000006ac05693): fill_kobj_path: path = '/devices/virtual/block/loop1'
kobject: 'loop3' (00000000d1e05784): kobject_uevent_env
kobject: 'loop3' (00000000d1e05784): fill_kobj_path: path = '/devices/virtual/block/loop3'
kobject: 'loop5' (000000000d8855a4): kobject_uevent_env
kobject: 'loop5' (000000000d8855a4): fill_kobj_path: path = '/devices/virtual/block/loop5'
kobject: 'loop5' (000000000d8855a4): kobject_uevent_env
kobject: 'loop5' (000000000d8855a4): fill_kobj_path: path = '/devices/virtual/block/loop5'
kobject: 'loop1' (000000006ac05693): kobject_uevent_env
kobject: 'loop1' (000000006ac05693): fill_kobj_path: path = '/devices/virtual/block/loop1'
kobject: 'loop3' (00000000d1e05784): kobject_uevent_env
kobject: 'loop3' (00000000d1e05784): fill_kobj_path: path = '/devices/virtual/block/loop3'
kobject: 'loop5' (000000000d8855a4): kobject_uevent_env
kobject: 'loop5' (000000000d8855a4): fill_kobj_path: path = '/devices/virtual/block/loop5'
kobject: 'loop2' (00000000320db566): kobject_uevent_env
kobject: 'loop2' (00000000320db566): fill_kobj_path: path = '/devices/virtual/block/loop2'
kobject: 'loop4' (0000000000dcb711): kobject_uevent_env
kobject: 'loop4' (0000000000dcb711): fill_kobj_path: path = '/devices/virtual/block/loop4'
kobject: 'loop4' (0000000000dcb711): kobject_uevent_env
kobject: 'loop4' (0000000000dcb711): fill_kobj_path: path = '/devices/virtual/block/loop4'
Unknown ioctl -2143244695
Unknown ioctl -2143244695
kobject: 'loop4' (0000000000dcb711): kobject_uevent_env
kobject: 'loop4' (0000000000dcb711): fill_kobj_path: path = '/devices/virtual/block/loop4'
kobject: 'loop5' (000000000d8855a4): kobject_uevent_env
kobject: 'loop5' (000000000d8855a4): fill_kobj_path: path = '/devices/virtual/block/loop5'
kobject: 'loop2' (00000000320db566): kobject_uevent_env
kobject: 'loop2' (00000000320db566): fill_kobj_path: path = '/devices/virtual/block/loop2'
kobject: 'loop3' (00000000d1e05784): kobject_uevent_env
kobject: 'loop3' (00000000d1e05784): fill_kobj_path: path = '/devices/virtual/block/loop3'
kobject: 'loop1' (000000006ac05693): kobject_uevent_env
kobject: 'loop1' (000000006ac05693): fill_kobj_path: path = '/devices/virtual/block/loop1'
kobject: 'loop4' (0000000000dcb711): kobject_uevent_env
kobject: 'loop4' (0000000000dcb711): fill_kobj_path: path = '/devices/virtual/block/loop4'
kobject: 'loop4' (0000000000dcb711): kobject_uevent_env
kobject: 'loop4' (0000000000dcb711): fill_kobj_path: path = '/devices/virtual/block/loop4'
kobject: 'loop1' (000000006ac05693): kobject_uevent_env
kobject: 'loop1' (000000006ac05693): fill_kobj_path: path = '/devices/virtual/block/loop1'
kobject: 'loop5' (000000000d8855a4): kobject_uevent_env
kobject: 'loop5' (000000000d8855a4): fill_kobj_path: path = '/devices/virtual/block/loop5'
kobject: 'loop2' (00000000320db566): kobject_uevent_env
kobject: 'loop2' (00000000320db566): fill_kobj_path: path = '/devices/virtual/block/loop2'
kobject: 'loop3' (00000000d1e05784): kobject_uevent_env
kobject: 'loop3' (00000000d1e05784): fill_kobj_path: path = '/devices/virtual/block/loop3'
kobject: 'loop4' (0000000000dcb711): kobject_uevent_env
kobject: 'loop4' (0000000000dcb711): fill_kobj_path: path = '/devices/virtual/block/loop4'
kobject: 'loop1' (000000006ac05693): kobject_uevent_env
kobject: 'loop1' (000000006ac05693): fill_kobj_path: path = '/devices/virtual/block/loop1'
kobject: 'loop1' (000000006ac05693): kobject_uevent_env
kobject: 'loop1' (000000006ac05693): fill_kobj_path: path = '/devices/virtual/block/loop1'
kobject: 'loop4' (0000000000dcb711): kobject_uevent_env
kobject: 'loop4' (0000000000dcb711): fill_kobj_path: path = '/devices/virtual/block/loop4'
kobject: 'loop3' (00000000d1e05784): kobject_uevent_env
kobject: 'loop3' (00000000d1e05784): fill_kobj_path: path = '/devices/virtual/block/loop3'
kobject: 'loop2' (00000000320db566): kobject_uevent_env
kobject: 'loop2' (00000000320db566): fill_kobj_path: path = '/devices/virtual/block/loop2'
kobject: 'loop5' (000000000d8855a4): kobject_uevent_env
kobject: 'loop5' (000000000d8855a4): fill_kobj_path: path = '/devices/virtual/block/loop5'
kobject: 'loop1' (000000006ac05693): kobject_uevent_env
kobject: 'loop1' (000000006ac05693): fill_kobj_path: path = '/devices/virtual/block/loop1'
kobject: 'loop1' (000000006ac05693): kobject_uevent_env
kobject: 'loop1' (000000006ac05693): fill_kobj_path: path = '/devices/virtual/block/loop1'
kobject: 'loop5' (000000000d8855a4): kobject_uevent_env
kobject: 'loop5' (000000000d8855a4): fill_kobj_path: path = '/devices/virtual/block/loop5'
kobject: 'loop2' (00000000320db566): kobject_uevent_env
kobject: 'loop2' (00000000320db566): fill_kobj_path: path = '/devices/virtual/block/loop2'
kobject: 'loop2' (00000000320db566): kobject_uevent_env
kobject: 'loop2' (00000000320db566): fill_kobj_path: path = '/devices/virtual/block/loop2'
kobject: 'loop3' (00000000d1e05784): kobject_uevent_env
kobject: 'loop3' (00000000d1e05784): fill_kobj_path: path = '/devices/virtual/block/loop3'
kobject: 'loop4' (0000000000dcb711): kobject_uevent_env
kobject: 'loop4' (0000000000dcb711): fill_kobj_path: path = '/devices/virtual/block/loop4'
9pnet: p9_fd_create_unix (24797): problem connecting socket: ./file0/../file0: -111
9pnet: p9_fd_create_unix (24798): problem connecting socket: ./file0/../file0: -111
kobject: 'loop2' (00000000320db566): kobject_uevent_env
kobject: 'loop2' (00000000320db566): fill_kobj_path: path = '/devices/virtual/block/loop2'
kobject: 'loop3' (00000000d1e05784): kobject_uevent_env
kobject: 'loop3' (00000000d1e05784): fill_kobj_path: path = '/devices/virtual/block/loop3'
kobject: 'loop1' (000000006ac05693): kobject_uevent_env
kobject: 'loop1' (000000006ac05693): fill_kobj_path: path = '/devices/virtual/block/loop1'
kobject: 'loop5' (000000000d8855a4): kobject_uevent_env
kobject: 'loop5' (000000000d8855a4): fill_kobj_path: path = '/devices/virtual/block/loop5'
kobject: 'loop4' (0000000000dcb711): kobject_uevent_env
kobject: 'loop4' (0000000000dcb711): fill_kobj_path: path = '/devices/virtual/block/loop4'
kobject: 'loop4' (0000000000dcb711): kobject_uevent_env
kobject: 'loop4' (0000000000dcb711): fill_kobj_path: path = '/devices/virtual/block/loop4'
kobject: 'loop4' (0000000000dcb711): kobject_uevent_env
kobject: 'loop4' (0000000000dcb711): fill_kobj_path: path = '/devices/virtual/block/loop4'
kobject: 'loop3' (00000000d1e05784): kobject_uevent_env
kobject: 'loop3' (00000000d1e05784): fill_kobj_path: path = '/devices/virtual/block/loop3'
kobject: 'loop1' (000000006ac05693): kobject_uevent_env
kobject: 'loop1' (000000006ac05693): fill_kobj_path: path = '/devices/virtual/block/loop1'
kobject: 'loop5' (000000000d8855a4): kobject_uevent_env
kobject: 'loop5' (000000000d8855a4): fill_kobj_path: path = '/devices/virtual/block/loop5'
kobject: 'loop2' (00000000320db566): kobject_uevent_env
kobject: 'loop2' (00000000320db566): fill_kobj_path: path = '/devices/virtual/block/loop2'
kobject: 'loop5' (000000000d8855a4): kobject_uevent_env
kobject: 'loop5' (000000000d8855a4): fill_kobj_path: path = '/devices/virtual/block/loop5'
kobject: 'loop5' (000000000d8855a4): kobject_uevent_env
kobject: 'loop5' (000000000d8855a4): fill_kobj_path: path = '/devices/virtual/block/loop5'
kobject: 'loop2' (00000000320db566): kobject_uevent_env
kobject: 'loop2' (00000000320db566): fill_kobj_path: path = '/devices/virtual/block/loop2'
kobject: 'loop2' (00000000320db566): kobject_uevent_env
kobject: 'loop2' (00000000320db566): fill_kobj_path: path = '/devices/virtual/block/loop2'
kobject: 'loop3' (00000000d1e05784): kobject_uevent_env
kobject: 'loop3' (00000000d1e05784): fill_kobj_path: path = '/devices/virtual/block/loop3'
kobject: 'loop4' (0000000000dcb711): kobject_uevent_env
kobject: 'loop4' (0000000000dcb711): fill_kobj_path: path = '/devices/virtual/block/loop4'
kobject: 'loop1' (000000006ac05693): kobject_uevent_env
kobject: 'loop1' (000000006ac05693): fill_kobj_path: path = '/devices/virtual/block/loop1'
kobject: 'loop4' (0000000000dcb711): kobject_uevent_env
kobject: 'loop4' (0000000000dcb711): fill_kobj_path: path = '/devices/virtual/block/loop4'
overlayfs: unrecognized mount option "Rn*'Üfowner<" or missing value
kobject: 'loop4' (0000000000dcb711): kobject_uevent_env
kobject: 'loop4' (0000000000dcb711): fill_kobj_path: path = '/devices/virtual/block/loop4'
kobject: 'loop3' (00000000d1e05784): kobject_uevent_env
kobject: 'loop3' (00000000d1e05784): fill_kobj_path: path = '/devices/virtual/block/loop3'
kobject: 'loop1' (000000006ac05693): kobject_uevent_env
kobject: 'loop1' (000000006ac05693): fill_kobj_path: path = '/devices/virtual/block/loop1'
kobject: 'loop2' (00000000320db566): kobject_uevent_env
kobject: 'loop2' (00000000320db566): fill_kobj_path: path = '/devices/virtual/block/loop2'
kobject: 'loop5' (000000000d8855a4): kobject_uevent_env
kobject: 'loop5' (000000000d8855a4): fill_kobj_path: path = '/devices/virtual/block/loop5'
kobject: 'loop2' (00000000320db566): kobject_uevent_env
kobject: 'loop2' (00000000320db566): fill_kobj_path: path = '/devices/virtual/block/loop2'
nf_conntrack: default automatic helper assignment has been turned off for security reasons and CT-based  firewall rule not found. Use the iptables CT target to attach helpers instead.
9pnet: p9_fd_create_tcp (25002): problem connecting socket to 127.0.0.1
kobject: 'loop2' (00000000320db566): kobject_uevent_env
kobject: 'loop2' (00000000320db566): fill_kobj_path: path = '/devices/virtual/block/loop2'
kobject: 'loop5' (000000000d8855a4): kobject_uevent_env
kobject: 'loop5' (000000000d8855a4): fill_kobj_path: path = '/devices/virtual/block/loop5'
kobject: 'loop5' (000000000d8855a4): kobject_uevent_env
kobject: 'loop5' (000000000d8855a4): fill_kobj_path: path = '/devices/virtual/block/loop5'
kobject: 'loop4' (0000000000dcb711): kobject_uevent_env
kobject: 'loop4' (0000000000dcb711): fill_kobj_path: path = '/devices/virtual/block/loop4'
kobject: 'loop3' (00000000d1e05784): kobject_uevent_env
kobject: 'loop3' (00000000d1e05784): fill_kobj_path: path = '/devices/virtual/block/loop3'
kobject: 'loop1' (000000006ac05693): kobject_uevent_env
kobject: 'loop1' (000000006ac05693): fill_kobj_path: path = '/devices/virtual/block/loop1'
kobject: 'loop5' (000000000d8855a4): kobject_uevent_env
kobject: 'loop5' (000000000d8855a4): fill_kobj_path: path = '/devices/virtual/block/loop5'
kobject: 'loop5' (000000000d8855a4): kobject_uevent_env
kobject: 'loop5' (000000000d8855a4): fill_kobj_path: path = '/devices/virtual/block/loop5'
kobject: 'loop1' (000000006ac05693): kobject_uevent_env
kobject: 'loop1' (000000006ac05693): fill_kobj_path: path = '/devices/virtual/block/loop1'
kobject: 'loop2' (00000000320db566): kobject_uevent_env
kobject: 'loop2' (00000000320db566): fill_kobj_path: path = '/devices/virtual/block/loop2'