=== build ===
$ cc -O -o /root/df3516 /root/df3516.c
BUILD_OK

=== guest env ===
DragonFly dfbsd 6.5-DEVELOPMENT #0: Thu Jul 2 06:02:54 UTC 2026 root@dfbsd:/usr/obj/usr/src/sys/X86_64_GENERIC x86_64
modules: netgraph.ko, ng_socket.ko (stock, /boot/kernel)
PoC run as root (control sockets root-gated)