------------[ cut here ]------------
WARNING: CPU: 1 PID: 5713 at net/ipv6/xfrm6_tunnel.c:341 xfrm6_tunnel_net_exit+0x7e/0x100
Modules linked in:
CPU: 1 UID: 0 PID: 5713 Comm: kworker/u8:2 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
Workqueue: netns cleanup_net
RIP: 0010:xfrm6_tunnel_net_exit+0x7e/0x100
Code: e8 06 df f7 4b 83 3c 2c 00 75 19 e8 0c 9b 7b f7 49 81 fd f8 07 00 00 74 1d e8 fe 9a 7b f7 49 83 c5 08 eb c9 e8 f3 9a 7b f7 90 <0f> 0b 90 49 81 fd f8 07 00 00 75 e3 48 81 c3 00 08 00 00 45 31 f6
RSP: 0018:ffffc90002daf8b0 EFLAGS: 00010293
RAX: ffffffff8a44103d RBX: ffff8881103ec000 RCX: ffff888107938000
RDX: 0000000000000000 RSI: ffffffff8be33660 RDI: ffff8881103ec2e8
RBP: ffffc90002daf9b0 R08: ffffffff8fa38637 R09: 1ffffffff1f470c6
R10: dffffc0000000000 R11: fffffbfff1f470c7 R12: ffff8881103ec000
R13: 00000000000002e8 R14: ffff88810fac8000 R15: dffffc0000000000
FS:  0000000000000000(0000) GS:ffff8881a3c18000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f601dbb0d58 CR3: 000000012cbc0000 CR4: 00000000000006f0
Call Trace:
 <TASK>
 ops_undo_list+0x49a/0x990
 cleanup_net+0x4c5/0x800
 process_scheduled_works+0xae1/0x17b0
 worker_thread+0x8a0/0xda0
 kthread+0x711/0x8a0
 ret_from_fork+0x3fc/0x770
 ret_from_fork_asm+0x1a/0x30
 </TASK>
