---
id: CVE-2026-89501
title: 'ring-buffer: Hold cpu_buffer::lock when resizing a subbuf'
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  ring-buffer: Hold cpu_buffer::lock when resizing a subbuf

  Because, ring_buffer_subbuf_order_set() can clear cpu_buffer->free_page,
  hold cpu_buffer->lock to prevent rac…
severity: high
cvss: 7.8
cvssVector: 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H'
cvssSource: cna
cwe:
  - CWE-413
vendor: Linux
product: Linux
affected:
  - >-
    Linux >= 8e7b58c27b3c567316a51079b375b846f9223bba <
    8a496aaa3da6e8d545896c2370c7e617cc931ae2
  - >-
    Linux >= 8e7b58c27b3c567316a51079b375b846f9223bba <
    6fcb0b745a0b80df62eae4a93ce52a2d061f4ac2
  - >-
    Linux >= 8e7b58c27b3c567316a51079b375b846f9223bba <
    bf242baf58de03467f226c8e29554c9495dca7fc
  - >-
    Linux >= 8e7b58c27b3c567316a51079b375b846f9223bba <
    24974bd0da1b47fd56c975533ead50abf754e74d
  - Linux 6.8
published: '2026-09-11'
updated: '2026-10-19'
sourceUpdated: '2026-10-19T08:47:52.839Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-89501'
references:
  - url: 'https://git.kernel.org/stable/c/8a496aaa3da6e8d545896c2370c7e617cc931ae2'
  - url: 'https://git.kernel.org/stable/c/6fcb0b745a0b80df62eae4a93ce52a2d061f4ac2'
  - url: 'https://git.kernel.org/stable/c/bf242baf58de03467f226c8e29554c9495dca7fc'
  - url: 'https://git.kernel.org/stable/c/24974bd0da1b47fd56c975533ead50abf754e74d'
  - url: >-
      https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-89501.json
  - url: 'https://access.redhat.com/security/cve/CVE-2026-89501'
  - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2532254'
  - url: 'https://www.cve.org/CVERecord?id=CVE-2026-89501'
  - url: 'https://nvd.nist.gov/vuln/detail/CVE-2026-89501'
  - url: >-
      https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-89501.mbox
tags:
  - cve.org
  - csaf
  - vex
  - red-hat
epss: 0.00168
epssPercentile: 0.06065
scores:
  cna: 7.8
  vendor: 7
ingestedAt: '2026-09-14T15:23:07.475Z'
---

## Overview

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

ring-buffer: Hold cpu_buffer::lock when resizing a subbuf

Because, ring_buffer_subbuf_order_set() can clear cpu_buffer->free_page,
hold cpu_buffer->lock to prevent races with
ring_buffer_alloc_read_page() and ring_buffer_free_read_page().

## Affected

- `Linux >= 8e7b58c27b3c567316a51079b375b846f9223bba < 8a496aaa3da6e8d545896c2370c7e617cc931ae2`
- `Linux >= 8e7b58c27b3c567316a51079b375b846f9223bba < 6fcb0b745a0b80df62eae4a93ce52a2d061f4ac2`
- `Linux >= 8e7b58c27b3c567316a51079b375b846f9223bba < bf242baf58de03467f226c8e29554c9495dca7fc`
- `Linux >= 8e7b58c27b3c567316a51079b375b846f9223bba < 24974bd0da1b47fd56c975533ead50abf754e74d`
- `Linux 6.8`

## Remediation

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

## Vendor advisories

- **Red Hat VEX** · Moderate · affected: Red Hat Enterprise Linux 10 · no fix planned: Red Hat Enterprise Linux 10 · updated 2026-09-18 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-89501.json)