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DF-0005 PoC verification environment
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Tested at: 2026-07-02 (UTC)

--- guest uname ---
DragonFly dfbsd 6.5-DEVELOPMENT DragonFly v6.5.0.1712.g89e6a-DEVELOPMENT #1: Mon Jun 29 14:18:01 UTC 2026     root@ephemeral-5c2002c44b6c:/usr/obj/usr/src/sys/X86_64_GENERIC  x86_64

--- compiler ---
cc 8.3 [DragonFly] Release/2019-02-22

--- caller identity (PoC runs as this unprivileged user) ---
uid=1001(maxx) gid=1001(maxx) groups=1001(maxx)
(maxx is NOT in wheel)

--- TIOCSTI killswitch sysctl search (all negative => no killswitch) ---
sysctl: unknown oid 'kern.tty_tiocsti'
sysctl: unknown oid 'kern.legacy_tiocsti'
sysctl: unknown oid 'dev.tty.legacy_tiocsti'
(no tiocsti sysctl found anywhere in sysctl -a)

--- kernel source confirmed (read-only audit tree) ---
sys/kern/tty.c:1158  case TIOCSTI:
sys/kern/tty.c:1160      caps_priv_check_td(td, SYSCAP_RESTRICTEDROOT)  /* gated on (flag & FREAD)==0 */
sys/kern/tty.c:1167      caps_priv_check_td(td, SYSCAP_RESTRICTEDROOT)  /* gated on !isctty(p, tp)  */
sys/kern/tty.c:1172      (*linesw[tp->t_line].l_rint)(*(u_char *)data, tp);   /* inject sink */
sys/sys/tty.h:216        #define isctty(p, tp) ((p)->p_session == (tp)->t_session && ((p)->p_flags & P_CONTROLT))
sys/sys/fcntl.h:68       #define FREAD  0x0001

--- guest state after test ---
healthy (TIOCSTI inject is non-destructive; no panic, no reset needed)