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 https://www.openbsd.org/ddb.html describes the minimum info required in bug reports. Insufficient info makes it difficult to find and fix bugs.