{
  "finding_id": "DF-4567",
  "file": "sys/dev/drm/i915/intel_guc_ct.c",
  "title": "CTB ring math trusts GuC-firmware-written descriptor fields with only compiled-out GEM_BUG_ON validation (div-by-zero panic / FW-offset wild write)",
  "severity": "Info",
  "bucket": "base:dev",
  "verdict": "untested",
  "impact": "none",
  "confidence": "certain",
  "reproduce": {
    "build": "n/a — no PoC exists; path unreachable on this tree (no platform sets has_guc_ct; enable_guc defaults 0, root-only) and guest GPU is QEMU bochs std-VGA (no i915 device)",
    "run": "n/a",
    "expected": "n/a — static finding; trigger requires signed GuC firmware to write an out-of-contract descriptor (desc->size==0 => %0 panic at intel_guc_ct.c:366/373, :608/:624; inflated size/tail => wild cmds[tail] write past the 1-page CT object)"
  },
  "kernel_refs": [
    "sys/dev/drm/i915/intel_guc_ct.c:317",
    "sys/dev/drm/i915/intel_guc_ct.c:324",
    "sys/dev/drm/i915/intel_guc_ct.c:347",
    "sys/dev/drm/i915/intel_guc_ct.c:365",
    "sys/dev/drm/i915/intel_guc_ct.c:579",
    "sys/dev/drm/i915/intel_guc_ct.c:590",
    "sys/dev/drm/i915/intel_guc_fwif.h:382",
    "sys/dev/drm/i915/i915_gem.h:56",
    "sys/dev/drm/i915/intel_uc.c:218",
    "sys/dev/drm/i915/i915_params.h:49"
  ],
  "artifacts": [
    "README.md",
    "VERDICT.md",
    "fix.diff",
    "verdict.json",
    "manifest.json"
  ]
}