{
 "finding_id": "DF-3247",
 "status": "not_reproduced",
 "reproduced": 0,
 "impact": "none",
 "confidence": "certain",
 "verdict": "Line-accurate confirmation; runtime demonstration not attempted (requires a cd9660 -C KICONV mount with cd9660_iconv.ko and a high-byte filename; the DF-3124 rig on this guest showed the KICONV mount plumbing is itself broken - iconv_open of the empty pair fails - so the demonstration would test that other bug instead). Mechanism confirmed from source: on an input sequence absent from the conversion table, convchr consumes ZERO bytes and writes zero output, so sgetrune computes len=consumed=0, returns c=0 and does NOT advance fn (cd9660_util.c:206-215); when the image name is exhausted first, isofncmp hits return d with d==0 at :112-113 - an exact match for a non-equal name. Fix: on zero consumption fall back to consuming one raw byte (no false match); compiled in the F40FIX build.",
 "exploit_chain": "",
 "evidence": "VERDICT.md with path:line citations; run.log where a live demo exists; fix.diff",
 "kernel_refs": [
  "sys/vfs/isofs/cd9660/cd9660_util.c:112",
  "sys/vfs/isofs/cd9660/cd9660_util.c:206"
 ],
 "poc_changes": "n/a - KICONV mount path unavailable on this guest (see DF-3124)",
 "attempts": 0,
 "guest_uname": "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",
 "runtime_sec": 30,
 "guest_dirty": 0,
 "build_cmd": "see build.sh",
 "run_cmd": "see run.sh",
 "code_hash": null,
 "notes": "",
 "recommended_fix": "sgetrune: when convchr consumes nothing, consume one raw byte instead of returning a stale c=0",
 "fix_status": "compile_validated",
 "fix_verdict": "fix.diff applied in the F40FIX verification kernel build (RC=0, zero -Werror errors); no runtime A/B for this item (line-certain hardening)"
}