---
id: CVE-2025-21874
title: 'dm-integrity: Avoid divide by zero in table status in Inline mode'
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  dm-integrity: Avoid divide by zero in table status in Inline mode

  In Inline mode, the journal is unused, and journal_sectors is zero.

  Calculating the journal watermar…
severity: none
vendor: Linux
product: Linux
affected:
  - >-
    Linux >= fb0987682c629c1d2c476f35f6fde405a5e304a4 <
    22c6f577b3cb184857b440ae5e5916f6c9e7021d
  - >-
    Linux >= fb0987682c629c1d2c476f35f6fde405a5e304a4 <
    06d9895f265282e939a8933bb18de82eba2b4dda
  - >-
    Linux >= fb0987682c629c1d2c476f35f6fde405a5e304a4 <
    7fb39882b20c98a9a393c244c86b56ef6933cff8
  - Linux 6.11
ssvc:
  exploitation: none
  automatable: 'no'
  technicalImpact: partial
  timestamp: '2026-11-05T20:36:06.022549Z'
published: '2025-03-27'
updated: '2026-11-05'
sourceUpdated: '2026-11-05T20:41:46.172Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2025-21874'
references:
  - url: 'https://git.kernel.org/stable/c/22c6f577b3cb184857b440ae5e5916f6c9e7021d'
  - url: 'https://git.kernel.org/stable/c/06d9895f265282e939a8933bb18de82eba2b4dda'
  - url: 'https://git.kernel.org/stable/c/7fb39882b20c98a9a393c244c86b56ef6933cff8'
tags:
  - cve.org
epss: 0.00203
epssPercentile: 0.10347
ingestedAt: '2026-11-05T22:38:31.852Z'
---

## Overview

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

dm-integrity: Avoid divide by zero in table status in Inline mode

In Inline mode, the journal is unused, and journal_sectors is zero.

Calculating the journal watermark requires dividing by journal_sectors,
which should be done only if the journal is configured.

Otherwise, a simple table query (dmsetup table) can cause OOPS.

This bug did not show on some systems, perhaps only due to
compiler optimization.

On my 32-bit testing machine, this reliably crashes with the following:

 : Oops: divide error: 0000 [#1] PREEMPT SMP
 : CPU: 0 UID: 0 PID: 2450 Comm: dmsetup Not tainted 6.14.0-rc2+ #959
 : EIP: dm_integrity_status+0x2f8/0xab0 [dm_integrity]
 ...

## Affected

- `Linux >= fb0987682c629c1d2c476f35f6fde405a5e304a4 < 22c6f577b3cb184857b440ae5e5916f6c9e7021d`
- `Linux >= fb0987682c629c1d2c476f35f6fde405a5e304a4 < 06d9895f265282e939a8933bb18de82eba2b4dda`
- `Linux >= fb0987682c629c1d2c476f35f6fde405a5e304a4 < 7fb39882b20c98a9a393c244c86b56ef6933cff8`
- `Linux 6.11`

## Remediation

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