baseline kernel: DragonFly dfbsd 6.5-DEVELOPMENT DragonFly 6.5-DEVELOPMENT #0: Thu Jul  2 06:02:54 UTC 2026  root@dfbsd:/usr/obj/usr/src/sys/X86_64_GENERIC  x86_64
fixed kernel:    DragonFly dfbsd 6.5-DEVELOPMENT DragonFly 6.5-DEVELOPMENT #1: Mon Sep  7 11:10:39 UTC 2026  root@dfbsd:/usr/obj/usr/src/sys/X86_64_GENERIC  x86_64
stack INVARIANTS kernel (stock snapshot); no SMAP/SMEP/KASLR
udf: kldload'able module (VFS_SET(udf_vfsops, udf, VFCF_READONLY))
devices: vn0 = /tmp/df3164-base.udf (crafted good image), vn1 = /tmp/df3164-garbage.img (1 MB zeros)
privilege: all setup run as root (mount(2) requires the mount cap); trigger program is a plain mount(2) caller