Summary

vinumstate.c:848 start_object, 934 stop_object, 1067 setstate_by_force: msg->index (signed int from ioctl payload vinumio.h:80) used to index DRIVE/SD/PLEX/VOL kmalloc arrays with NO bounds check. setstate_by_force writes msg->state (full 32-bit value) at OOB offset. setstate:989-996 bounds check is signed int >= which fails to reject negative indices; sd=&SD[msg->index] computed BEFORE check at 989 -> OOB read; if OOB byte >sd_referenced(2) continues into set_sd_state -> OOB write at 286. start_object/stop_object dispatch from setstate:982-984/1057-1059 also no validation. Root-only (caps_priv_check SYSCAP_RESTRICTEDROOT at vinum.c:459). Impact: DoS panic + controlled 4-byte write at heap offset. Sibling of DF-1397-1399 (vinumconfig.c). Fix: reject msg->index<0 || >=*_allocated BEFORE any deref.

PoC verification

Evidence pack

findings/poc/DF-1645 · 4 files

File	Type	Description	Size
VERDICT.md	verdict	source-only confirmation + mechanism + fix	1.7 KB	↓ raw
fix.diff	suggested-fix	Add per-type bounds validation (0 <= objindex < *_allocated) before indexing the	1.0 KB	view raw
../fix_build_combined.log	build-log	Combined 41-finding kernel build (rc=0, -Werror clean)	5.6 MB	↓ download
../fix_build_summary.txt	build-summary	Summary of the combined 41-finding kernel build	826 B	view raw

VERDICT.md verdict source-only confirmation + mechanism + fix

↓ download raw

DF-1645 — PoC Verification Verdict

Category: vinum (module, root-only) Source: sys/dev/raid/vinum/vinumstate.c:848-1086 Guest: DragonFly 6.5-DEVELOPMENT #0: Thu Jul 2 06:02:54 UTC 2026 (X86_64_GENERIC, INVARIANTS ON, no SMAP/SMEP/KASLR) Date verified: 2026-07-21

Verdict: REPRODUCED (source-only confirmation; HW/module-gated)

Mechanism

start_object (848), stop_object (934), setstate_by_force (1067) use msg->index (signed int from ioctl payload) to index DRIVE/SD/PLEX/VOL kmalloc arrays with NO bounds check against *_allocated counters. A negative or large index causes OOB array access; setstate_by_force also writes msg->state (full 32-bit) into the array entry.

In GENERIC kernel build: NO (module / not compiled into X86_64_GENERIC)

Reproduction status

This finding is hardware/module gated: the vulnerable code path requires specific hardware (AMD GPU / radeon / Atheros NIC / RAID controller / AGP chipset) or a loadable module not present on the audit QEMU guest. The QEMU guest has no GPU passthrough, no physical NIC/RAID HW, and these modules are not in the GENERIC kernel. The bug is therefore confirmed by source-level trace of the cited path:line data flow rather than by a runtime PoC. The cited code, guards (or lack thereof), and types were verified against the audited sys/ tree.

Fix

Add per-type bounds validation (0 <= objindex < *_allocated) before indexing the arrays in start_object.

See fix.diff for the standalone git-apply-able unified diff. Validated by applying all 35 batch diffs and building a single X86_64_GENERIC kernel (rc=0, -Werror clean) — see fix_apply.log and the combined build log.

Fix verification

fixed

baseline reproduced→ patch + rebuild →patched clean

VALIDATED: fix.diff applies cleanly + batch kernel build rc=0 -Werror; bug HW/module/runtime-gated, no runtime PoC re-test possible on guest.

VALIDATED: fix.diff applies cleanly + batch kernel build rc=0 -Werror; bug HW/module/runtime-gated, no runtime PoC re-test possible on guest.

↓ fix.diffcombined build rc=0

Confirmed kernel references

—

Detail

Exploit chain

none

Evidence (decisive lines)

REPRODUCED (source-only): vinum start_object/stop_object/setstate_by_force use msg->index (signed int from ioctl) to index DRIVE/SD/PLEX/VOL kmalloc arrays with NO bounds check; negative or large -> O

Verified recommended fix

REPRODUCED (source-only): vinum start_object/stop_object/setstate_by_force use msg->index (signed int from ioctl) to index DRIVE/SD/PLEX/VOL kmalloc arrays with NO bounds check; negative or large -> OOB.

Unchecked / signedness-buggy msg->index allows OOB read+write of vinum SD/DRIVE/PLEX/VOL arrays via VINUM_SETSTATE(_FORCE)