# CVE-2026-99135: dm-integrity: fix infinite loop on discard with large tag size


- **Severity:** Not scored
- **Exploited in the wild:** Not known
- **Fix available:** Yes
- **Published:** 28 Oct 2026
- **Updated:** 28 Oct 2026
- **Also known as:** AZL-111254, BELL-CVE-2026-99135, DEBIAN-CVE-2026-99135, GHSA-9xjj-2vj5-5vwq, UBUNTU-CVE-2026-99135

## What is CVE-2026-99135?

CVE-2026-99135 is a vulnerability in Linux, published on 28 Oct 2026. 

### Official description

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.

## Which versions are affected by CVE-2026-99135?


## How do I fix CVE-2026-99135?

Upgrade to a fixed version.

## Is CVE-2026-99135 being exploited?

There is no known exploitation of CVE-2026-99135 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-99135 and fix it if it is affected.

What it is: CVE-2026-99135 is a vulnerability in Linux, published on 28 Oct 2026. 
Exploitation: There is no known exploitation of CVE-2026-99135 in the wild and no public exploit code.

Affected product: Linux. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-99135/ (Markdown: https://insights.sbomify.com/CVE-2026-99135/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-99135
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-99135
- OSV: https://osv.dev/vulnerability/CVE-2026-99135

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-99135/
Summaries are generated and may contain mistakes; the official description above is the record.