panic: vref used where vget required (4)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: ffe6655cba7d Do not get muddled and crash if focusing a pa..
git tree: openbsd
console output: https://syzkaller.appspot.com/x/log.txt?x=14387623180000
kernel config: https://syzkaller.appspot.com/x/.config?x=1bc15e68cd2a49e5
dashboard link: https://syzkaller.appspot.com/bug?extid=9591948825036c029128

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

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/4273f6b8ebd7/disk-ffe6655c.raw.xz
bsd.gdb: https://storage.googleapis.com/syzbot-assets/dfef2689bc91/bsd-ffe6655c.gdb.xz
kernel image: https://storage.googleapis.com/syzbot-assets/367e05c7dc04/kernel-ffe6655c.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+959194...@syzkaller.appspotmail.com

panic: vref used where vget required
Starting stack trace...
panic(ffffffff828aa485) at panic+0x159 sys/kern/subr_prf.c:229
vref(fffffd807e0098c8) at vref+0x83 sys/kern/vfs_subr.c:698
namei(ffff800035be7ad8) at namei+0x3b2 sys/kern/vfs_lookup.c:221
dofchownat(ffff80002a6b22b8,ffffff9c,20000040,0,ffffffff,0) at dofchownat+0xb3 sys/kern/vfs_syscalls.c:2440
syscall(ffff800035be7d80) at syscall+0x72a sys/arch/amd64/amd64/trap.c:577
Xsyscall() at Xsyscall+0x128
end of kernel
end trace frame: 0x20671d74240, count: 251
End of stack trace.


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