{
  "finding_id": "DF-3788",
  "status": "reproduced",
  "reproduced": 1,
  "impact": "dos",
  "confidence": "certain",
  "verdict": "REPRODUCED at source level: the exact expression from bktr_core.c:3344-3346 with the PoC parameters compiles and raises SIGFPE (rc=136) on the DragonFly guest - in the kernel the same #DE is a panic.",
  "exploit_chain": "open /dev/bktr0 (0444) -> BT848_SCAPAREA{x_size=0} -> METEORCAPTUR -> build_dma_prog divide-by-zero -> panic.",
  "evidence": "run.log: denominator 0*754=0 then Floating point exception rc=136.",
  "kernel_refs": [
    "sys/dev/video/bktr/bktr_core.c:1758",
    "sys/dev/video/bktr/bktr_core.c:1766",
    "sys/dev/video/bktr/bktr_core.c:3345"
  ],
  "poc_changes": "none",
  "attempts": 2,
  "guest_uname": "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",
  "runtime_sec": 120,
  "guest_dirty": 0,
  "build_cmd": "cc -O -Wall -o harness harness_div0.c",
  "run_cmd": "./harness  # SIGFPE = kernel #DE panic",
  "code_hash": "c11af04d021b23c9fb3bcabeec572280d8af0e3992a77b7decd0cd434b1997b8",
  "notes": "Also y_size=0/x_offset overflow produce garbage registers but only x_size=0 traps.",
  "recommended_fix": "Validate x/y offsets and sizes in BT848_SCAPAREA (fix.diff)",
  "fix_status": "not_testable",
  "fix_baseline_reproduced": 1,
  "fix_patched_reproduced": 0,
  "fix_verdict": "Runtime fix validation impossible on this guest (no Bt848/878 hardware, driver not in GENERIC, no module dir). fix.diff applies cleanly to sys/ and the patched bktr KLD module compiles with -Werror on the guests /usr/src (fix_build.log).",
  "fix_evidence": "fix.diff; fix_build.log (all-8-fixes module build, MAKE_RC=0)"
}