panic: vput: null vp

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: e24fbf55691f Add pool to allocate individual rtkit task ar..
git tree: openbsd
console output: https://syzkaller.appspot.com/x/log.txt?x=127be335980000
kernel config: https://syzkaller.appspot.com/x/.config?x=7058272de1526588
dashboard link: https://syzkaller.appspot.com/bug?extid=e66df12522464841cea6

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

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/982a1d089c32/disk-e24fbf55.raw.xz
bsd.gdb: https://storage.googleapis.com/syzbot-assets/802160f45461/bsd-e24fbf55.gdb.xz
kernel image: https://storage.googleapis.com/syzbot-assets/59f7887ac187/kernel-e24fbf55.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+e66df1...@syzkaller.appspotmail.com

panic: vput: null vp
Starting stack trace...
panic(ffffffff82fe4708) at panic+0x1d0 sys/kern/subr_prf.c:229
vput(0) at vput+0x1a5 sys/kern/vfs_subr.c:779
ufs_rename(64bdf01e) at ufs_rename+0x177e sys/ufs/ufs/ufs_vnops.c:1054
end trace frame: 0x0, count: 254
End of stack trace.


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