DF-4577 / manifest.json
{ "finding_id": "DF-4577", "manifest_version": 1, "title": "intel_hdcp_validate_v_prime KSV fill shift missing -sha_leftovers: repeater SHA-1 input stream corrupted for >=2 downstream devices, HDCP1.4 repeater auth always fails (fail-closed)", "file": "sys/dev/drm/i915/intel_hdcp.c", "verdict_summary": { "status": "untested", "kernel_level": "hardware-gated (no i915-class GPU in guest; needs Intel HSW/gen8+ display + HDCP repeater sink + DRM_MASTER)", "analytical": "proven by guest-compiled arithmetic simulation (run.log) + upstream v5.17 fix diff", "impact": "none (kernel memory safety); fail-closed loss of HDCP repeater content-protection" }, "reproduce": { "build": "./build.sh", "run": "./run.sh", "expected": "For N>=2: 'DF (old)' row diverges from the required stream at byte 5 (got 7 = 5|6, want 5); 'upstream' row emits the exact concatenation. N=1 correct in both." }, "kernel_refs": [ "sys/dev/drm/i915/intel_hdcp.c:221-223", "sys/dev/drm/i915/intel_hdcp.c:237-239", "sys/dev/drm/i915/intel_hdcp.c:262-360", "sys/dev/drm/i915/intel_hdcp.c:383-392", "sys/dev/drm/i915/intel_hdcp.c:444-455", "sys/dev/drm/i915/intel_hdcp.c:679-692" ], "upstream_fix_ref": "torvalds/linux v5.17+ drivers/gpu/drm/i915/display/intel_hdcp.c:529 ((sizeof(sha_text) - j - 1 - sha_leftovers) * 8); DF tree matches pre-v5.17 form (v4.17/v4.18/v5.4/v5.15-era)", "artifacts": [ "README.md", "VERDICT.md", "df4577_sim.c", "build.sh", "run.sh", "build.log", "run.log", "env.txt", "fix.diff", "manifest.json", "verdict.json" ] } |