------------[ cut here ]------------
conntrack cleanup blocked for 60s
WARNING: net/netfilter/nf_conntrack_core.c:2505 at nf_conntrack_cleanup_net_list+0x21f/0x360 net/netfilter/nf_conntrack_core.c:2504, CPU#0: kworker/u8:34/20540
Modules linked in:
CPU: 0 UID: 0 PID: 20540 Comm: kworker/u8:34 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/07/2026
Workqueue: netns cleanup_net
RIP: 0010:nf_conntrack_cleanup_net_list+0x21f/0x360 net/netfilter/nf_conntrack_core.c:2504
Code: 4c 89 ef e8 b3 69 35 f8 4d 8b 7d 00 4d 39 ef 74 69 e8 65 89 c4 f7 45 31 e4 e9 a5 fe ff ff e8 58 89 c4 f7 48 8d 3d 21 ae 86 07 <67> 48 0f b9 3a eb c0 89 e9 80 e1 07 80 c1 03 38 c1 0f 8c da fe ff
RSP: 0018:ffffc90007c4f8b0 EFLAGS: 00010293
RAX: ffffffff8a038728 RBX: dffffc0000000000 RCX: ffff888020338000
RDX: 0000000000000000 RSI: ffffffffffffffff RDI: ffffffff918a3550
RBP: 0000000000000001 R08: ffff888050281003 R09: 1ffff1100a050200
R10: dffffc0000000000 R11: ffffed100a050201 R12: 000000010002b2e7
R13: ffffc90007c4fa50 R14: ffffc90007c4fa50 R15: 000000010002b2e8
FS:  0000000000000000(0000) GS:ffff888123abd000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000555557d81a38 CR3: 00000000431e2000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 ops_exit_list net/core/net_namespace.c:206 [inline]
 ops_undo_list+0x4b4/0x8d0 net/core/net_namespace.c:253
 cleanup_net+0x572/0x810 net/core/net_namespace.c:706
 process_one_work kernel/workqueue.c:3396 [inline]
 process_scheduled_works+0xc3d/0x1630 kernel/workqueue.c:3479
 worker_thread+0xa47/0xfb0 kernel/workqueue.c:3560
 kthread+0x38b/0x480 kernel/kthread.c:436
 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
----------------
Code disassembly (best guess):
   0:	4c 89 ef             	mov    %r13,%rdi
   3:	e8 b3 69 35 f8       	call   0xf83569bb
   8:	4d 8b 7d 00          	mov    0x0(%r13),%r15
   c:	4d 39 ef             	cmp    %r13,%r15
   f:	74 69                	je     0x7a
  11:	e8 65 89 c4 f7       	call   0xf7c4897b
  16:	45 31 e4             	xor    %r12d,%r12d
  19:	e9 a5 fe ff ff       	jmp    0xfffffec3
  1e:	e8 58 89 c4 f7       	call   0xf7c4897b
  23:	48 8d 3d 21 ae 86 07 	lea    0x786ae21(%rip),%rdi        # 0x786ae4b
* 2a:	67 48 0f b9 3a       	ud1    (%edx),%rdi <-- trapping instruction
  2f:	eb c0                	jmp    0xfffffff1
  31:	89 e9                	mov    %ebp,%ecx
  33:	80 e1 07             	and    $0x7,%cl
  36:	80 c1 03             	add    $0x3,%cl
  39:	38 c1                	cmp    %al,%cl
  3b:	0f                   	.byte 0xf
  3c:	8c da                	mov    %ds,%edx
  3e:	fe                   	(bad)
  3f:	ff                   	.byte 0xff