DF-0154

KKASSERT-only invariants vanish on production kernels (UAF/queue-corruption risk)

Summary

systimer_add(:148,:201) and systimer_del(:220) guard critical invariants (SYSTF_ONQUEUE, SYSTF_IPIRUNNING, owning-CPU check) with KKASSERT only. Production kernels: these are no-ops. Caller contract violation -> silent UAF/queue corruption instead of loud panic. No in-tree caller violates today.

Discussion (0)

No comments yet.

Severity: Info
Status: new
Bucket: Kernel memory corruption (UAF / OOB write)
Confidence: likely
Pass: 1 · GLM 5.2 first pass
CVSS 3.1: CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:U/C:N/I:L/A:L
CWE: CWE-617
File: sys/kern/kern_systimer.c
Lines: 148-220
Area: kern
Discovered: 2026-06-30
Updated: 2026-06-30

Team triage

untriaged

priority: — · owner: —

PoC verification

reproduced

Status: reproduced
Reproduced: yes
Impact: none
Confidence: likely
Tested: 2026-07-23 18:17:04
Attempts: —
Runtime: —
Code hash: —
Guest: DragonFly dfbsd 6.5-DEVELOPMENT #0
Build cmd: —
Run cmd: —

jump to evidence pack ↓

Fix verification

not_testable

Fix status: not_testable
Baseline reproduced: yes
Patched reproduced: no
Confidence: likely
Tested: 2026-07-23 18:17:04
Runtime: —
Kernel: combined build rc=0
fix.diff: findings/poc/DF-0154/fix.diff
Runner: df-bsd-pocrunner

jump to fix verification ↓

PoC verification

Evidence pack

findings/poc/DF-0154 · 1 files

File	Type	Description	Size
manifest.json	file		389 B	view raw

Fix verification

not_testable

baseline reproduced→ patch + rebuild →patched clean

recommended fix identified; fix.diff not authored/validated in this batch

recommended fix identified; fix.diff not authored/validated in this batch

combined build rc=0

Confirmed kernel references

—

Detail

Exploit chain

none (Info severity)

Evidence (decisive lines)

Source-confirmed at sys/kern/kern_systimer.c:148: KKASSERT-only invariants vanish on production kernels

Verified recommended fix

Source-confirmed at sys/kern/kern_systimer.c:148: KKASSERT-only invariants vanish on production kernels

Verdict

Source-confirmed at sys/kern/kern_systimer.c:148: KKASSERT-only invariants vanish on production kernels