---
id: CVE-2025-68250
title: |-
  In the Linux kernel, the following vulnerability has been resolved:

  hung_task: fix warnings caused by unaligned lock pointers

  The blocker tracking mechanism assumes that lock pointers are at least
  4-byte aligned to use their lower bits…
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  hung_task: fix warnings caused by unaligned lock pointers

  The blocker tracking mechanism assumes that lock pointers are at least
  4-byte aligned to use their lower bits…
severity: high
cvss: 8.2
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:H'
published: '2025-12-16'
updated: '2026-10-14'
sourceUpdated: '2026-10-14T13:10:00.187'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2025-68250'
references:
  - url: 'https://git.kernel.org/stable/c/c0e2dcbe54cb15ecdf9d8f4501c6720423243888'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/c97513cddcfc235f2522617980838e500af21d01'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
tags:
  - nvd
epss: 0.00307
epssPercentile: 0.21783
ingestedAt: '2026-10-14T13:30:58.466Z'
---

## Overview

In the Linux kernel, the following vulnerability has been resolved:

hung_task: fix warnings caused by unaligned lock pointers

The blocker tracking mechanism assumes that lock pointers are at least
4-byte aligned to use their lower bits for type encoding.

However, as reported by Eero Tamminen, some architectures like m68k
only guarantee 2-byte alignment of 32-bit values. This breaks the
assumption and causes two related WARN_ON_ONCE checks to trigger.

To fix this, the runtime checks are adjusted to silently ignore any lock
that is not 4-byte aligned, effectively disabling the feature in such
cases and avoiding the related warnings.

Thanks to Geert Uytterhoeven for bisecting!

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.