---
id: CVE-2026-74349
title: 'ocfs2: reject FITRIM ranges shorter than a cluster'
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  ocfs2: reject FITRIM ranges shorter than a cluster

  ocfs2_trim_mainbm() trims the global bitmap in cluster units, but its
  too-short range validation only checks sb->s_b…
severity: high
cvss: 7.1
cvssVector: 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H'
cvssSource: cna
vendor: Linux
product: Linux
affected:
  - >-
    Linux >= aa89762c54800208d5afdcd8e6bf124818f17fe0 <
    d903d59c0315f59bdf0214b4f13d71c9feb2c45c
  - >-
    Linux >= aa89762c54800208d5afdcd8e6bf124818f17fe0 <
    441abb77222f155e8d931dbabb465466db01cfd7
  - >-
    Linux >= aa89762c54800208d5afdcd8e6bf124818f17fe0 <
    e652d0f5108e447b22da4249bcd23dd1b63c73dd
  - >-
    Linux >= aa89762c54800208d5afdcd8e6bf124818f17fe0 <
    346314bb0cc2fc52b50b73d6ecc62e0217455c2e
  - >-
    Linux >= aa89762c54800208d5afdcd8e6bf124818f17fe0 <
    06c0a0431b9856506fcd9b2c1b0c6136567d756d
  - >-
    Linux >= aa89762c54800208d5afdcd8e6bf124818f17fe0 <
    3fa7139b5f42731a61f78c42433adae13f9adc21
  - >-
    Linux >= aa89762c54800208d5afdcd8e6bf124818f17fe0 <
    2c13e02592b918be7725ab5965e01ef4e46c4b57
  - >-
    Linux >= aa89762c54800208d5afdcd8e6bf124818f17fe0 <
    ca1afd88f5eaaff9168e1466e5401385edf59543
  - Linux 3.14
ssvc:
  exploitation: none
  automatable: 'no'
  technicalImpact: partial
  timestamp: '2026-10-16T18:54:14.069402Z'
published: '2026-08-15'
updated: '2026-10-16'
sourceUpdated: '2026-10-16T18:55:34.720Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-74349'
references:
  - url: 'https://git.kernel.org/stable/c/d903d59c0315f59bdf0214b4f13d71c9feb2c45c'
  - url: 'https://git.kernel.org/stable/c/441abb77222f155e8d931dbabb465466db01cfd7'
  - url: 'https://git.kernel.org/stable/c/e652d0f5108e447b22da4249bcd23dd1b63c73dd'
  - url: 'https://git.kernel.org/stable/c/346314bb0cc2fc52b50b73d6ecc62e0217455c2e'
  - url: 'https://git.kernel.org/stable/c/06c0a0431b9856506fcd9b2c1b0c6136567d756d'
  - url: 'https://git.kernel.org/stable/c/3fa7139b5f42731a61f78c42433adae13f9adc21'
  - url: 'https://git.kernel.org/stable/c/2c13e02592b918be7725ab5965e01ef4e46c4b57'
  - url: 'https://git.kernel.org/stable/c/ca1afd88f5eaaff9168e1466e5401385edf59543'
tags:
  - cve.org
epss: 0.00171
epssPercentile: 0.06095
ingestedAt: '2026-10-16T19:46:24.376Z'
---

## Overview

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

ocfs2: reject FITRIM ranges shorter than a cluster

ocfs2_trim_mainbm() trims the global bitmap in cluster units, but its
too-short range validation only checks sb->s_blocksize.

On filesystems with a cluster size larger than the block size, a FITRIM
range that is at least one block but shorter than one cluster is accepted
and shifted down to len == 0.  The later start + len - 1 and len -= ... 
arithmetic then underflows and can drive trimming past the requested
range.

Reject ranges shorter than s_clustersize instead.  That preserves the
existing -EINVAL behavior for requests that cannot discard even one
allocation unit and keeps zero-cluster trims out of the group walk.

## Affected

- `Linux >= aa89762c54800208d5afdcd8e6bf124818f17fe0 < d903d59c0315f59bdf0214b4f13d71c9feb2c45c`
- `Linux >= aa89762c54800208d5afdcd8e6bf124818f17fe0 < 441abb77222f155e8d931dbabb465466db01cfd7`
- `Linux >= aa89762c54800208d5afdcd8e6bf124818f17fe0 < e652d0f5108e447b22da4249bcd23dd1b63c73dd`
- `Linux >= aa89762c54800208d5afdcd8e6bf124818f17fe0 < 346314bb0cc2fc52b50b73d6ecc62e0217455c2e`
- `Linux >= aa89762c54800208d5afdcd8e6bf124818f17fe0 < 06c0a0431b9856506fcd9b2c1b0c6136567d756d`
- `Linux >= aa89762c54800208d5afdcd8e6bf124818f17fe0 < 3fa7139b5f42731a61f78c42433adae13f9adc21`
- `Linux >= aa89762c54800208d5afdcd8e6bf124818f17fe0 < 2c13e02592b918be7725ab5965e01ef4e46c4b57`
- `Linux >= aa89762c54800208d5afdcd8e6bf124818f17fe0 < ca1afd88f5eaaff9168e1466e5401385edf59543`
- `Linux 3.14`

## Remediation

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