# DF-1417 — Verification Verdict

## Verdict: CONFIRMED-BY-SOURCE-TRACE (HW-gated)

**Status:** inconclusive (HW-gated / not reachable as unprivileged maxx)
**Impact:** none (cannot reproduce on QEMU guest — no GPU/HW, or root/operator-only)
**Confidence:** certain (source-trace confirmed bug is real)

## Mechanism

smu8_get_clock_by_type (:1613): clocks->count=smu8_get_max_sclk_level() returns SMU reply (unvalidated). clocks->clock[MAX_NUM_CLOCKS=16] is stack-allocated in caller. count>16 → stack OOB write via clocks->clock[i]=.... Also OOB reads display_clock[8] (:1615) and table->entries[count] (:1619, VBIOS-sized).

**Source:** `sys/dev/drm/amd/powerplay/hwmgr/smu8_hwmgr.c:1613`

## Why it cannot be reproduced on this guest

HW-gated. amdgpu powerplay requires AMD GPU with SMU8 (Carrizo/Stoney). No GPU in QEMU guest.

## Phase 6: Escalation Assessment

This is a **HW-gated GPU module (amdgpu powerplay SMU8)** finding. The primitive is not reachable from the
unprivileged maxx user on this guest (no hardware / module not loaded / root-only device).
No escalation chain is possible because the trigger path is not exercisable.

For GPU findings: the module (radeon.ko/amdgpu.ko/i915.ko) is a loadable module not
present in the GENERIC kernel and requires actual GPU hardware absent from the QEMU guest.
For root/operator findings: the device node is mode 0600 or 0640 root:operator, and maxx
(uid 1001) has no operator group membership.

## Fix

Clamp clocks->count to MAX_NUM_CLOCKS after smu8_get_max_sclk_level() returns.

**Fix description:** Clamp smu8_get_max_sclk_level() result to MAX_NUM_CLOCKS before array writes.

The full git-apply-able diff is in `fix.diff`. It applies cleanly to the audit source tree
and compiles as part of the kernel build (validated via `make nativekernel` rc=0).

## Classification

- **status:** inconclusive
- **reproduced:** 0
- **impact:** none
- **fix_status:** not_testable (HW-gated: PoC cannot run on guest; diff applies + compiles verified)