[    2.798604] ------------[ cut here ]------------
[    2.798770] refcount_t: underflow; use-after-free.
[    2.798857] WARNING: CPU: 2 PID: 227 at lib/refcount.c:28 refcount_warn_saturate+0xbc/0x110
[    2.798977] Modules linked in:
[    2.799018] CPU: 2 UID: 0 PID: 227 Comm: packetdrill Not tainted 6.18.0-rc4-virtme #1 PREEMPT(voluntary) 
[    2.799095] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[    2.799153] RIP: 0010:refcount_warn_saturate+0xbc/0x110
[    2.799203] Code: b7 e8 18 df ba ff 90 0f 0b 90 90 c3 80 3d 79 c9 eb 00 00 75 89 c6 05 70 c9 eb 00 01 90 48 c7 c7 f0 8d 51 b7 e8 f5 de ba ff 90 <0f> 0b 90 90 c3 80 3d 54 c9 eb 00 00 0f 85 62 ff ff ff c6 05 47 c9
[    2.799379] RSP: 0018:ffffa11bc05afe50 EFLAGS: 00010286
[    2.799434] RAX: 0000000000000000 RBX: ffffa11bc05afe60 RCX: 00000000ffffdfff
[    2.799502] RDX: 0000000000000000 RSI: 00000000ffffffea RDI: 0000000000000001
[    2.799577] RBP: ffffa11bc05af988 R08: ffffffffb7956a28 R09: 00000000ffffdfff
[    2.799645] R10: ffffffffb7876a40 R11: ffffffffb7926a40 R12: dead000000000122
[    2.799713] R13: 00000000fffb768c R14: 0000000000000001 R15: ffff8f948367c000
[    2.799783] FS:  000000001d1fe3c0(0000) GS:ffff8f9506ce6000(0000) knlGS:0000000000000000
[    2.799854] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[    2.799915] CR2: 00007f40ab75e000 CR3: 000000000375e003 CR4: 0000000000772ef0
[    2.799978] PKRU: 55555554
[    2.800004] Call Trace:
[    2.800026]  <TASK>
[    2.800052]  netdev_run_todo+0x21a/0x550
[    2.800096]  ? __tun_detach+0x2ed/0x490
[    2.800133]  tun_chr_close+0x47/0xa0
[    2.800170]  __fput+0xda/0x290
[    2.800210]  __x64_sys_close+0x3d/0x80
[    2.800247]  do_syscall_64+0xa4/0xfd0
[    2.800286]  entry_SYSCALL_64_after_hwframe+0x4b/0x53
[    2.800334] RIP: 0033:0x4901eb
[    2.800376] Code: 03 00 00 00 0f 05 48 3d 00 f0 ff ff 77 41 c3 48 83 ec 18 89 7c 24 0c e8 c3 78 04 00 8b 7c 24 0c 41 89 c0 b8 03 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 35 44 89 c7 89 44 24 0c e8 21 79 04 00 8b 44
[    2.800526] RSP: 002b:00007ffedfe5b0a0 EFLAGS: 00000293 ORIG_RAX: 0000000000000003
[    2.800598] RAX: ffffffffffffffda RBX: 00007ffedfe5b5f8 RCX: 00000000004901eb
[    2.800662] RDX: 0000000000000002 RSI: 0000000000000002 RDI: 0000000000000005
[    2.800730] RBP: 00007ffedfe5b0e0 R08: 0000000000000000 R09: 0000000000000000
[    2.800797] R10: 000000001d206230 R11: 0000000000000293 R12: 00007ffedfe5b578
[    2.800865] R13: 0000000000000001 R14: 000000000054e030 R15: 0000000000000001
[    2.800928]  </TASK>
[    2.800954] ---[ end trace 0000000000000000 ]---