syzbot

panic: ffs_blkfree: bad size
Stopped at      db_enter+0x18:  addq    $0x8,%rsp
    TID    PID    UID     PRFLAGS     PFLAGS  CPU  COMMAND
*488332  30506      0         0x2          0    1K syz-executor.0
db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:398
panic() at panic+0x15c sys/kern/subr_prf.c:212
ffs_blkfree(fffffd807aa3e550,16,4000) at ffs_blkfree+0xa0b sys/ufs/ffs/ffs_alloc.c:1280
ffs_truncate(fffffd807aa3e550,0,0,ffffffffffffffff) at ffs_truncate+0x1291 sys/ufs/ffs/ffs_inode.c:365
ufs_inactive(ffff800020c0ac68) at ufs_inactive+0x159 sys/ufs/ufs/ufs_inode.c:85
VOP_INACTIVE(fffffd8065d666f0,ffff800020b39650) at VOP_INACTIVE+0x4c sys/kern/vfs_vops.c:572
vput(fffffd8065d666f0) at vput+0xb6 sys/kern/vfs_subr.c:765
ufs_remove(ffff800020c0ad58) at ufs_remove+0x13c sys/ufs/ufs/ufs_vnops.c:620
VOP_REMOVE(fffffd806ec287a0,fffffd8065d666f0,ffff800020c0ae48) at VOP_REMOVE+0x61 sys/kern/vfs_vops.c:378
dounlinkat(ffff800020b39650,ffffff9c,7f7fffff38c0,0) at dounlinkat+0x195 sys/kern/vfs_syscalls.c:1805
syscall(ffff800020c0afd0) at syscall+0x552 mi_syscall sys/sys/syscall_mi.h:92 [inline]
syscall(ffff800020c0afd0) at syscall+0x552 sys/arch/amd64/amd64/trap.c:554
Xsyscall(6,a,7f7fffff38c0,a,4515bf181c0,7f7fffff3d80) at Xsyscall+0x128
end of kernel
end trace frame: 0x7f7fffff3d70, count: 3
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