panic: ffs_freefile: freeing free inode

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: b226cd0be9f7 regen
git tree: openbsd
console output: https://syzkaller.appspot.com/x/log.txt?x=1349c105180000
kernel config: https://syzkaller.appspot.com/x/.config?x=7058272de1526588
dashboard link: https://syzkaller.appspot.com/bug?extid=101949af3bf76119b35f

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

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/0e7a1709922a/disk-b226cd0b.raw.xz
bsd.gdb: https://storage.googleapis.com/syzbot-assets/a1c14c0c4b47/bsd-b226cd0b.gdb.xz
kernel image: https://storage.googleapis.com/syzbot-assets/d9bd487f4a13/kernel-b226cd0b.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+101949...@syzkaller.appspotmail.com

panic: ffs_freefile: freeing free inode
Starting stack trace...
panic(ffffffff828b76c8) at panic+0x16f sys/kern/subr_prf.c:229
ffs_freefile(fffffd806f75eef0,1fa85,2000) at ffs_freefile+0x374
ffs_inode_free(fffffd806f75eef0,1fa85,2000) at ffs_inode_free+0x3b sys/ufs/ffs/ffs_alloc.c:1355
ufs_inactive(ffff80002d6bbc78) at ufs_inactive+0x1e0 sys/ufs/ufs/ufs_inode.c:94
VOP_INACTIVE(fffffd8065db3db0,ffff80002bb2e050) at VOP_INACTIVE+0xc5 sys/kern/vfs_vops.c:489
vput(fffffd8065db3db0) at vput+0xac sys/kern/vfs_subr.c:779
ufs_remove(ffff80002d6bbd78) at ufs_remove+0x136 sys/ufs/ufs/ufs_vnops.c:601
VOP_REMOVE(fffffd8065db3468,fffffd8065db3db0,ffff80002d6bbe58) at VOP_REMOVE+0x11c sys/kern/vfs_vops.c:333
dounlinkat(ffff80002bb2e050,ffffff9c,7dab6aa51620,0) at dounlinkat+0x110 sys/kern/vfs_syscalls.c:1891
syscall(ffff80002d6bbfd0) at syscall+0x854 mi_syscall sys/sys/syscall_mi.h:180 [inline]
syscall(ffff80002d6bbfd0) at syscall+0x854 sys/arch/amd64/amd64/trap.c:577
Xsyscall() at Xsyscall+0x128
end of kernel
end trace frame: 0x7dab6aa51ad0, count: 246
End of stack trace.


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