panic: mutex ADDR not held in in_pcb_iterator

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 51e28e2b9751 Add config option for vmd(8) to run guest in ..
git tree: openbsd
console output: https://syzkaller.appspot.com/x/log.txt?x=14a3a1d4580000
kernel config: https://syzkaller.appspot.com/x/.config?x=1bc15e68cd2a49e5
dashboard link: https://syzkaller.appspot.com/bug?extid=685e153e3bff59033007

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/d8d9cb53b15f/disk-51e28e2b.raw.xz
bsd.gdb: https://storage.googleapis.com/syzbot-assets/047e56b5855b/bsd-51e28e2b.gdb.xz
kernel image: https://storage.googleapis.com/syzbot-assets/43b3767d91cc/kernel-51e28e2b.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+685e15...@syzkaller.appspotmail.com

panic: mutex 0xffffffff83998828 not held in in_pcb_iterator
Starting stack trace...
panic(ffffffff833b836a) at panic+0x1ba sys/kern/subr_prf.c:229
in_pcb_iterator(ffffffff83998828,fffffd806ec2b3d8,ffff80003c9775a0) at in_pcb_iterator+0x20c sys/netinet/in_pcb.c:683
sysctl_file(ffff80003c977868,4,200000000100,ffff80003c977898,ffff80002a822550) at sysctl_file+0xa52 sys/kern/kern_sysctl.c:-1
kern_sysctl(ffff80003c977864,5,200000000100,ffff80003c977898,0,37,430a24c97e600c) at kern_sysctl+0x251 sys/kern/kern_sysctl.c:526
sys_sysctl(ffff80002a822550,ffff80003c9779d0,ffff80003c977920) at sys_sysctl+0x3f2 sys/kern/kern_sysctl.c:-1
syscall(ffff80003c9779d0) at syscall+0x97e mi_syscall sys/sys/syscall_mi.h:-1 [inline]
syscall(ffff80003c9779d0) at syscall+0x97e sys/arch/amd64/amd64/trap.c:579
Xsyscall() at Xsyscall+0x128
end of kernel
end trace frame: 0xc82d83b5710, count: 250
End of stack trace.


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