⬢ DragonFlyBSD Kernel Audit
DF-4641 / verdict.json
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{
  "finding_id": "DF-4641",
  "poc_id": "DF-4641",
  "status": "untested",
  "reproduced": 0,
  "impact": "Kernel-side over-read of adjacent physical space (other devices MMIO / unclaimed holes) into rdev->bios, parsed by atom/combios; possible read side effects on neighboring devices; no userspace exposure path found",
  "confidence": "likely",
  "attempts": 0,
  "guest_uname": null,
  "code_hash": null,
  "exploit_chain": [],
  "evidence": "DF-specific function (absent from FreeBSD drm2): maps the architectural 256KB maximum regardless of the ROM BARs actual decode (as little as 2KB per the vga_pci mask), and maps device MMIO WRITE-BACK cached instead of uncacheable. Sibling vga_pci path is rman-bounded. Low, hardware-gated.",
  "kernel_refs": [
    "sys/dev/drm/radeon/radeon_bios.c:133",
    "sys/dev/drm/radeon/radeon_bios.c:134",
    "sys/dev/drm/radeon/radeon_bios.c:140",
    "sys/dev/drm/radeon/radeon_bios.c:146",
    "sys/dev/drm/radeon/radeon_bios.c:153"
  ],
  "verdict": "not_run: needs a radeon GPU with a sub-256KB ROM BAR; guest has none",
  "fix_status": "not_testable",
  "fix_baseline_reproduced": 0,
  "fix_patched_reproduced": 0,
  "fix_verdict": "not_testable",
  "fix_evidence": "probe-BAR-size + map_uncacheable + cap-kmemdup fix in finding markdown"
}