CVE-2025-38008

Source
https://nvd.nist.gov/vuln/detail/CVE-2025-38008
Import Source
https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2025-38008.json
JSON Data
https://api.osv.dev/v1/vulns/CVE-2025-38008
Downstream
Published
2025-06-18T10:15:32Z
Modified
2025-06-18T14:01:35Z
Summary
[none]
Details

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

mm/page_alloc: fix race condition in unaccepted memory handling

The page allocator tracks the number of zones that have unaccepted memory using staticbranchenc/dec() and uses that static branch in hot paths to determine if it needs to deal with unaccepted memory.

Borislav and Thomas pointed out that the tracking is racy: operations on static_branch are not serialized against adding/removing unaccepted pages to/from the zone.

Sanity checks inside static_branch machinery detects it:

WARNING: CPU: 0 PID: 10 at kernel/jumplabel.c:276 _statickeyslowdeccpuslocked+0x8e/0xa0

The comment around the WARN() explains the problem:

/*
 * Warn about the '-1' case though; since that means a
 * decrement is concurrent with a first (0->1) increment. IOW
 * people are trying to disable something that wasn't yet fully
 * enabled. This suggests an ordering problem on the user side.
 */

The effect of this static_branch optimization is only visible on microbenchmark.

Instead of adding more complexity around it, remove it altogether.

References

Affected packages

Debian:13 / linux

Package

Name
linux
Purl
pkg:deb/debian/linux?arch=source

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0Unknown introduced version / All previous versions are affected
Fixed
6.12.30-1

Ecosystem specific

{
    "urgency": "not yet assigned"
}