CVE-2025-68250
hung_task: fix warnings caused by unaligned lock pointers
- State
- Published
- Severity
- 8.2 High
- Published
- Dec 16, 2025
- Updated
- Aug 5, 2026
- Reserved
- Dec 16, 2025
Description
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!
Scores
| CVSS | Score | Vector | Source |
|---|---|---|---|
| 3.1 | 8.2 High | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:H | Linux |
Weaknesses
The record names no weakness.
Affected Products
| Product | Versions |
|---|---|
LinuxLinux |
|
LinuxLinux |
|
References
Every record here comes from the CVE Program’s CVE List. © 1999–2026 The MITRE Corporation. CVE is a registered trademark of The MITRE Corporation. The records are reproduced under the CVE Program terms of use.