---
id: CVE-2026-99135
title: 'dm-integrity: fix infinite loop on discard with large tag size'
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  dm-integrity: fix infinite loop on discard with large tag size

  When integrity_metadata handles a discard, it fills a buffer with
  DISCARD_FILLER and writes it over the …
severity: none
vendor: Linux
product: Linux
affected:
  - >-
    Linux >= 84597a44a9d86ac949900441cea7da0af0f2f473 <
    fc512700f1413fed652dac22fa1c4e837210b9c0
  - >-
    Linux >= 84597a44a9d86ac949900441cea7da0af0f2f473 <
    251b44b424920df9204e88a81fb3f78fa48ddd99
  - >-
    Linux >= 84597a44a9d86ac949900441cea7da0af0f2f473 <
    18d80c77b4c7dd20699e81cedfbbff4e9d198f28
  - Linux 5.7
published: '2026-10-28'
updated: '2026-10-28'
sourceUpdated: '2026-10-28T10:34:47.902Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-99135'
references:
  - url: 'https://git.kernel.org/stable/c/fc512700f1413fed652dac22fa1c4e837210b9c0'
  - url: 'https://git.kernel.org/stable/c/251b44b424920df9204e88a81fb3f78fa48ddd99'
  - url: 'https://git.kernel.org/stable/c/18d80c77b4c7dd20699e81cedfbbff4e9d198f28'
tags:
  - cve.org
ingestedAt: '2026-10-28T11:09:40.434Z'
---

## Overview

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

dm-integrity: fix infinite loop on discard with large tag size

When integrity_metadata handles a discard, it fills a buffer with
DISCARD_FILLER and writes it over the tags, max_blocks blocks at a
time. If the kmalloc fails, the buffer is the on-stack array
checksums_onstack and max_size is set to HASH_MAX_DIGESTSIZE. So if the
tag size is larger than HASH_MAX_DIGESTSIZE, max_blocks is zero, bi_size
is never decremented and the loop never terminates.

Fix this by using sizeof(checksums_onstack) as max_size. The array has
MAX_TAG_SIZE bytes since commit b93b6643e9b5 ("dm integrity: fix a
crash with unusually large tag size"), so max_blocks is at least 1.

## Affected

- `Linux >= 84597a44a9d86ac949900441cea7da0af0f2f473 < fc512700f1413fed652dac22fa1c4e837210b9c0`
- `Linux >= 84597a44a9d86ac949900441cea7da0af0f2f473 < 251b44b424920df9204e88a81fb3f78fa48ddd99`
- `Linux >= 84597a44a9d86ac949900441cea7da0af0f2f473 < 18d80c77b4c7dd20699e81cedfbbff4e9d198f28`
- `Linux 5.7`

## Remediation

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