⬢ DragonFlyBSD Kernel Audit
DF-3636 / verdict.json
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{
  "finding_id": "DF-3636",
  "status": "untested",
  "reproduced": 0,
  "impact": "none",
  "confidence": "certain",
  "verdict": "Source-certain debug-print DoS, not runtime-testable on this guest (no i915 device). kprintf(\"i915_gem_fault: CHUNKING PASS\\n\") at sys/dev/drm/i915/i915_gem.c:2323 executes once per GTT page fault on the partial-view path (object > mappable aperture /2), i.e. up to hundreds of thousands of console-rendered printfs from one unprivileged DRM_RENDER_ALLOW mmap loop (MMAP_GTT registered at i915_drv.c:3247). DragonFly-port debug residue absent from the Linux original. Local console stall / log-flood DoS; no memory-safety impact. Fix: delete the print (fix.diff).",
  "exploit_chain": "open render node -> GEM_CREATE(>=256MB-1GB) -> MMAP_GTT + mmap + touch all pages -> one console printf per 4K fault -> console/log flooding, system-wide slowdown.",
  "evidence": "VERDICT.md; fix.diff (removal). Decisive line: i915_gem.c:2323 inside the IS_ERR(vma) partial-view branch taken per-fault for oversized objects.",
  "kernel_refs": [
    "sys/dev/drm/i915/i915_gem.c:2323",
    "sys/dev/drm/i915/i915_gem.c:2315",
    "sys/dev/drm/i915/i915_gem.c:4853",
    "sys/dev/drm/i915/i915_drv.c:3247"
  ],
  "poc_changes": "No runnable PoC (no i915 device on audit guest); trigger documented in README.md.",
  "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": 0,
  "guest_dirty": 0,
  "build_cmd": "",
  "run_cmd": "",
  "code_hash": "",
  "notes": "Low severity: hardening/DoS only. Companion error-path kprintfs (i915_gem.c:2301,2307,2345,2353,2359,2478,2500) fire only on exceptional conditions; CHUNKING PASS is the only unconditional per-fault print.",
  "recommended_fix": "Remove the kprintf at i915_gem.c:2323 (fix.diff).",
  "fix_status": "not_testable",
  "fix_baseline_reproduced": 0,
  "fix_patched_reproduced": 0,
  "fix_verdict": "Trivial deletion; cannot be kernel-validated on this guest (no i915 device).",
  "fix_evidence": "fix.diff."
}