CVE-2025-21874: dm-integrity: Avoid divide by zero in table status in Inline mode

Q: Which systems are exposed to this issue?

Systems using the Linux device-mapper integrity target in Inline mode are exposed. In this mode the journal is unused and its sector count is zero, which can trigger the faulty status calculation.

Q: What is required to trigger the failure?

A local user or process with sufficient privileges to run a device-mapper table status query can trigger it. The reported trigger is a simple dmsetup table query against an affected inline-mode dm-integrity mapping.

Q: What is the impact of a successful trigger?

The status query can cause a divide-by-zero kernel OOPS and crash. The supplied severity vector indicates availability impact only, with no stated confidentiality or integrity impact.

Q: How can I determine whether a system is affected?

Check whether dm-integrity mappings are configured in Inline mode. On affected builds, querying the table status for such a mapping may produce a divide-error OOPS; however, the report notes that the issue may not reproduce on every system due to compiler optimization.

Published Mar 27, 2025

Updated

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 journalsectors is zero.

Calculating the journal watermark requires dividing by journalsectors, 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: dmintegritystatus+0x2f8/0xab0 [dmintegrity] ...

Affected Software

12 affected componentsFixes available

Linux Kernel

Linux Linux kernel>=6.11<6.12.18

Linux Linux kernel>=6.13<6.13.6

Linux Linux kernel=6.14-rc1

Linux Linux kernel=6.14-rc2

Linux Linux kernel=6.14-rc3

Linux Linux kernel=6.14-rc4

debian/linux<6.12.19-1

6.12.19-1

debian/linux<6.12.19-1

6.12.19-1

linux/kernel>=6.11.0<6.12.18

6.12.18

linux/kernel>=6.13.0<6.13.6

6.13.6

debian/linux

6.1.176-16.1.190-16.12.107-16.12.115-27.2.15-1

Remediation

Recommended actions to resolve this vulnerability, in priority order.

Upgrade
Upgrade debian/linux to a version that resolves this vulnerability.
Fixed in 6.12.19-1
Upgrade
Upgrade linux/Kernel to a version that resolves this vulnerability.
Fixed in 6.12.18
Upgrade
Upgrade linux/Kernel to a version that resolves this vulnerability.
Fixed in 6.13.6
Upgrade
Upgrade debian/linux to a version that resolves this vulnerability.
Fixed in 6.1.176-1Fixed in 6.1.190-1Fixed in 6.12.107-1Fixed in 6.12.115-2Fixed in 7.2.15-1

Event History

Mar 27, 2025

CVE Published

via MITRE·02:57 PM

Data Sourced

via MITRE·02:57 PM

Description

Data Sourced

via OSV·02:57 PM

DescriptionAffected Software

Data Sourced

via NVD·03:15 PM

RemedyDescriptionSeverityWeaknessAffected Software

Data Sourced

via OSV·03:15 PM

Severity

Frequently Asked Questions

Which systems are exposed to this issue?

Systems using the Linux device-mapper integrity target in Inline mode are exposed. In this mode the journal is unused and its sector count is zero, which can trigger the faulty status calculation.

What is required to trigger the failure?

A local user or process with sufficient privileges to run a device-mapper table status query can trigger it. The reported trigger is a simple dmsetup table query against an affected inline-mode dm-integrity mapping.

What is the impact of a successful trigger?

The status query can cause a divide-by-zero kernel OOPS and crash. The supplied severity vector indicates availability impact only, with no stated confidentiality or integrity impact.

How can I determine whether a system is affected?

Check whether dm-integrity mappings are configured in Inline mode. On affected builds, querying the table status for such a mapping may produce a divide-error OOPS; however, the report notes that the issue may not reproduce on every system due to compiler optimization.

CVE-2025-21874: dm-integrity: Avoid divide by zero in table status in Inline mode

Affected Software

Remediation

Event History

Frequently Asked Questions

Which systems are exposed to this issue?

What is required to trigger the failure?

What is the impact of a successful trigger?

How can I determine whether a system is affected?

Company

Resources

Contact

Frequently Asked Questions

Which systems are exposed to this issue?

What is required to trigger the failure?

What is the impact of a successful trigger?

How can I determine whether a system is affected?