# DF-1398 — Verification Verdict

## Verdict: CONFIRMED-BY-SOURCE-TRACE (root/vinum-only)

**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

Four remove_*_entry functions use `>` instead of `>=` for bounds check: remove_drive_entry (:1731 driveno>drives_allocated), remove_sd_entry (:1758 sdno>subdisks_allocated), remove_plex_entry (:1812 plexno>plexes_allocated), remove_volume_entry (:1871 volno>volumes_allocated). When index==N_allocated, DRIVE[sdno]/SD[sdno]/PLEX[plexno]/VOL[volno] is dereferenced before check short-circuits (struct pointer taken at function entry). free_drive bzeros the OOB region. VINUM_REMOVE passes user msg->index unvalidated.

**Source:** `sys/dev/raid/vinum/vinumconfig.c:1731, 1758, 1812, 1871`

## Why it cannot be reproduced on this guest

Root/vinum-capability only. vinum is a volume manager controlled via /dev/vinum (root-only ioctl). Not reachable as unprivileged maxx.

## Phase 6: Escalation Assessment

This is a **Root-only (vinum volume manager)** 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

Change `>` to `>=` in all four remove_*_entry bounds checks.

**Fix description:** Change `>` to `>=` in all four remove_*_entry functions' bounds checks.

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)