------------[ cut here ]------------
refcount_t: increment on 0; use-after-free.
WARNING: CPU: 1 PID: 14368 at lib/refcount.c:156 refcount_inc_checked+0x4b/0x50 lib/refcount.c:156
Kernel panic - not syncing: panic_on_warn set ...
CPU: 1 PID: 14368 Comm: syz-executor.4 Not tainted 5.2.0+ #32
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x1d8/0x2f8 lib/dump_stack.c:113
 panic+0x29b/0x7d9 kernel/panic.c:219
 __warn+0x22f/0x230 kernel/panic.c:576
 report_bug+0x190/0x290 lib/bug.c:186
 fixup_bug arch/x86/kernel/traps.c:179 [inline]
 do_error_trap+0xd7/0x440 arch/x86/kernel/traps.c:272
 do_invalid_op+0x36/0x40 arch/x86/kernel/traps.c:291
 invalid_op+0x14/0x20 arch/x86/entry/entry_64.S:1008
RIP: 0010:refcount_inc_checked+0x4b/0x50 lib/refcount.c:156
Code: 3d 4e 9e 94 05 01 75 08 e8 22 d2 11 fe 5b 5d c3 e8 1a d2 11 fe c6 05 38 9e 94 05 01 48 c7 c7 79 c4 87 88 31 c0 e8 35 0d e3 fd <0f> 0b eb df 90 55 48 89 e5 41 57 41 56 41 55 41 54 53 48 83 e4 e0
RSP: 0018:ffff8880aeb09ba0 EFLAGS: 00010246
RAX: 86bd6da6db907b00 RBX: ffff8880829dd240 RCX: ffff88805c460500
RDX: 0000000000000302 RSI: 0000000000000302 RDI: 0000000000000000
RBP: ffff8880aeb09ba8 R08: ffffffff81600c14 R09: fffffbfff13bb2c0
R10: fffffbfff13bb2c0 R11: 0000000000000000 R12: ffff88809fb0cec0
R13: dffffc0000000000 R14: 0000000000000004 R15: ffff8880829dd1c0
 sock_hold include/net/sock.h:649 [inline]
 sk_add_node include/net/sock.h:701 [inline]
 nr_insert_socket net/netrom/af_netrom.c:137 [inline]
 nr_rx_frame+0x17bc/0x1e40 net/netrom/af_netrom.c:1023
 nr_loopback_timer+0x6a/0x140 net/netrom/nr_loopback.c:59
 call_timer_fn+0xec/0x200 kernel/time/timer.c:1322
 expire_timers kernel/time/timer.c:1366 [inline]
 __run_timers+0x7cd/0x9c0 kernel/time/timer.c:1685
 run_timer_softirq+0x4a/0x90 kernel/time/timer.c:1698
 __do_softirq+0x333/0x7c4 arch/x86/include/asm/paravirt.h:777
 do_softirq_own_stack+0x2a/0x40 arch/x86/entry/entry_64.S:1062
 </IRQ>
 do_softirq+0xfd/0x190 kernel/softirq.c:337
 __local_bh_enable_ip+0x194/0x240 kernel/softirq.c:189
 local_bh_enable+0x1f/0x30 include/linux/bottom_half.h:32
 get_next_corpse net/netfilter/nf_conntrack_core.c:2016 [inline]
 nf_ct_iterate_cleanup+0x2fa/0x390 net/netfilter/nf_conntrack_core.c:2039
 nf_ct_iterate_cleanup_net+0x154/0x1c0 net/netfilter/nf_conntrack_core.c:2124
 masq_device_event+0x9f/0xd0 net/netfilter/nf_nat_masquerade.c:88
 notifier_call_chain kernel/notifier.c:95 [inline]
 __raw_notifier_call_chain kernel/notifier.c:396 [inline]
 raw_notifier_call_chain+0xec/0x190 kernel/notifier.c:403
 call_netdevice_notifiers_info net/core/dev.c:1749 [inline]
 call_netdevice_notifiers_extack net/core/dev.c:1761 [inline]
 call_netdevice_notifiers net/core/dev.c:1775 [inline]
 dev_close_many+0x388/0x540 net/core/dev.c:1518
 dev_close+0x1bf/0x2b0 net/core/dev.c:1540
 __bond_release_one+0xd47/0x1470 drivers/net/bonding/bond_main.c:2002
 bond_release drivers/net/bonding/bond_main.c:2028 [inline]
 bond_do_ioctl+0x85e/0xcb0 drivers/net/bonding/bond_main.c:3554
 dev_ifsioc+0x66b/0xa60 net/core/dev_ioctl.c:322
 dev_ioctl+0x52e/0xcd0 net/core/dev_ioctl.c:489
 sock_do_ioctl+0x227/0x300 net/socket.c:1057
 sock_ioctl+0x4f8/0x730 net/socket.c:1185
 do_vfs_ioctl+0x7d4/0x1890 fs/ioctl.c:46
 ksys_ioctl fs/ioctl.c:713 [inline]
 __do_sys_ioctl fs/ioctl.c:720 [inline]
 __se_sys_ioctl fs/ioctl.c:718 [inline]
 __x64_sys_ioctl+0xe3/0x120 fs/ioctl.c:718
 do_syscall_64+0xfe/0x140 arch/x86/entry/common.c:296
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x459819
Code: fd b7 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 b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f9dfe031c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000459819
RDX: 00000000200000c0 RSI: 0000000000008991 RDI: 0000000000000005
RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f9dfe0326d4
R13: 00000000004c52ed R14: 00000000004d96d0 R15: 00000000ffffffff
Kernel Offset: disabled
Rebooting in 86400 seconds..