======================================
| [    1.794196] ------------[ cut here ]------------
| [    1.794239] refcount_t: underflow; use-after-free.
| [    1.794288] WARNING: CPU: 1 PID: 252 at lib/refcount.c:28 refcount_warn_saturate (lib/refcount.c:28 (discriminator 3))
| [    1.794354] Modules linked in:
[    1.794464] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[    1.794509] RIP: 0010:refcount_warn_saturate (lib/refcount.c:28 (discriminator 3))
[    1.794549] Code: bd e8 e8 54 ba ff 90 0f 0b 90 90 c3 80 3d 00 e6 2b 01 00 75 89 c6 05 f7 e5 2b 01 01 90 48 c7 c7 f8 48 b5 bd e8 c5 54 ba ff 90 <0f> 0b 90 90 c3 80 3d db e5 2b 01 00 0f 85 62 ff ff ff c6 05 ce e5
All code
========
   0:	bd e8 e8 54 ba       	mov    $0xba54e8e8,%ebp
   5:	ff 90 0f 0b 90 90    	call   *-0x6f6ff4f1(%rax)
   b:	c3                   	ret
   c:	80 3d 00 e6 2b 01 00 	cmpb   $0x0,0x12be600(%rip)        # 0x12be613
  13:	75 89                	jne    0xffffffffffffff9e
  15:	c6 05 f7 e5 2b 01 01 	movb   $0x1,0x12be5f7(%rip)        # 0x12be613
  1c:	90                   	nop
  1d:	48 c7 c7 f8 48 b5 bd 	mov    $0xffffffffbdb548f8,%rdi
  24:	e8 c5 54 ba ff       	call   0xffffffffffba54ee
  29:	90                   	nop
  2a:*	0f 0b                	ud2		<-- trapping instruction
  2c:	90                   	nop
  2d:	90                   	nop
  2e:	c3                   	ret
  2f:	80 3d db e5 2b 01 00 	cmpb   $0x0,0x12be5db(%rip)        # 0x12be611
  36:	0f 85 62 ff ff ff    	jne    0xffffffffffffff9e
  3c:	c6                   	.byte 0xc6
  3d:	05                   	.byte 0x5
  3e:	ce                   	(bad)
  3f:	e5                   	.byte 0xe5

Code starting with the faulting instruction
===========================================
   0:	0f 0b                	ud2
   2:	90                   	nop
   3:	90                   	nop
   4:	c3                   	ret
   5:	80 3d db e5 2b 01 00 	cmpb   $0x0,0x12be5db(%rip)        # 0x12be5e7
   c:	0f 85 62 ff ff ff    	jne    0xffffffffffffff74
  12:	c6                   	.byte 0xc6
  13:	05                   	.byte 0x5
  14:	ce                   	(bad)
  15:	e5                   	.byte 0xe5
[    1.794686] RSP: 0018:ffffa1b84059f868 EFLAGS: 00010286
[    1.794726] RAX: 0000000000000000 RBX: ffffa1b84059f878 RCX: 00000000ffffdfff
[    1.794779] RDX: 0000000000000000 RSI: 00000000ffffffea RDI: 0000000000000001
[    1.794831] RBP: ffffa1b84059f370 R08: ffffffffbe35ba28 R09: 00000000ffffdfff
[    1.794883] R10: ffffffffbe27ba40 R11: ffffffffbe32ba40 R12: dead000000000122
[    1.794937] R13: 00000000fffb729d R14: 0000000000000001 R15: ffff928883030000
[    1.794989] FS:  00007f55c3874b80(0000) GS:ffff928900211000(0000) knlGS:0000000000000000
[    1.795049] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[    1.795098] CR2: 00007f03000f0730 CR3: 000000000304e005 CR4: 0000000000772ef0
[    1.795162] PKRU: 55555554
[    1.795184] Call Trace:
[    1.795205]  <TASK>
[    1.795227]  netdev_run_todo (./include/linux/list.h:381 net/core/dev.c:11670)
[    1.795264]  rtnl_dellink (net/core/rtnetlink.c:3580)
[    1.795304]  ? update_load_avg (kernel/sched/fair.c:4731)
[    1.795338]  ? set_next_entity (kernel/sched/fair.c:894 kernel/sched/fair.c:5476)
[    1.795371]  ? finish_task_switch.isra.0 (./arch/x86/include/asm/irqflags.h:42 ./arch/x86/include/asm/irqflags.h:119 kernel/sched/sched.h:1559 kernel/sched/core.c:5073 kernel/sched/core.c:5191)
[    1.795413]  ? rtnl_bridge_getlink (net/core/rtnetlink.c:3536)
[    1.795455]  rtnetlink_rcv_msg (net/core/rtnetlink.c:6959)
[    1.795489]  ? rtnl_calcit.isra.0 (net/core/rtnetlink.c:6861)
[    1.795530]  netlink_rcv_skb (net/netlink/af_netlink.c:2550)
[    1.795565]  netlink_unicast (net/netlink/af_netlink.c:1319 net/netlink/af_netlink.c:1344)
[    1.795597]  ? __alloc_skb (net/core/skbuff.c:690)
[    1.795623]  netlink_sendmsg (net/netlink/af_netlink.c:1894)
[    1.795650]  __sys_sendto (net/socket.c:727 net/socket.c:742 net/socket.c:2244)
[    1.795686]  ? handle_mm_fault (mm/memory.c:6499)
[    1.795722]  ? do_user_addr_fault (arch/x86/mm/fault.c:1337)
[    1.795760]  __x64_sys_sendto (net/socket.c:2251 net/socket.c:2247 net/socket.c:2247)
[    1.795787]  do_syscall_64 (arch/x86/entry/syscall_64.c:63 arch/x86/entry/syscall_64.c:94)
[    1.795820]  entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:130)
[    1.795862] RIP: 0033:0x7f55c3987120
[    1.795897] Code: ff ff 64 89 02 eb bd 0f 1f 00 f3 0f 1e fa 41 89 ca 64 8b 04 25 18 00 00 00 85 c0 75 1d 45 31 c9 45 31 c0 b8 2c 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 68 c3 0f 1f 80 00 00 00 00 41 54 48 83 ec 20
All code
========
   0:	ff                   	(bad)
   1:	ff 64 89 02          	jmp    *0x2(%rcx,%rcx,4)
   5:	eb bd                	jmp    0xffffffffffffffc4
   7:	0f 1f 00             	nopl   (%rax)
   a:	f3 0f 1e fa          	endbr64
   e:	41 89 ca             	mov    %ecx,%r10d
  11:	64 8b 04 25 18 00 00 	mov    %fs:0x18,%eax
  18:	00 
  19:	85 c0                	test   %eax,%eax
  1b:	75 1d                	jne    0x3a
  1d:	45 31 c9             	xor    %r9d,%r9d
  20:	45 31 c0             	xor    %r8d,%r8d
  23:	b8 2c 00 00 00       	mov    $0x2c,%eax
  28:	0f 05                	syscall
  2a:*	48 3d 00 f0 ff ff    	cmp    $0xfffffffffffff000,%rax		<-- trapping instruction
  30:	77 68                	ja     0x9a
  32:	c3                   	ret
  33:	0f 1f 80 00 00 00 00 	nopl   0x0(%rax)
  3a:	41 54                	push   %r12
  3c:	48 83 ec 20          	sub    $0x20,%rsp

Code starting with the faulting instruction
===========================================
   0:	48 3d 00 f0 ff ff    	cmp    $0xfffffffffffff000,%rax
   6:	77 68                	ja     0x70
   8:	c3                   	ret
   9:	0f 1f 80 00 00 00 00 	nopl   0x0(%rax)
  10:	41 54                	push   %r12
  12:	48 83 ec 20          	sub    $0x20,%rsp
[    1.796026] RSP: 002b:00007ffc62d5b618 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
[    1.796085] RAX: ffffffffffffffda RBX: 0000000000000030 RCX: 00007f55c3987120
[    1.796139] RDX: 0000000000000030 RSI: 00007ffc62d5b620 RDI: 0000000000000005
[    1.796201] RBP: 00000000004047d0 R08: 0000000000000000 R09: 0000000000000000
[    1.796260] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000005


Finger prints:
refcount_warn_saturate:netdev_run_todo:rtnl_dellink:rtnetlink_rcv_msg:netlink_rcv_skb