# CVE-2026-98298: dmaengine: mmp_pdma: fix wrong sg length in mmp_pdma_prep_slave_sg()

> A bug in the Linux kernel MMP PDMA driver causes out-of-bounds reads and data loss due to incorrect scatterlist length handling, potentially exposing memory or corrupting data.

- **Severity:** Not scored
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 6 Oct 2026
- **Updated:** 19 Oct 2026
- **Also known as:** AZL-106131, BELL-CVE-2026-98298, DEBIAN-CVE-2026-98298, GHSA-262v-749m-59x9, UBUNTU-CVE-2026-98298

## What is CVE-2026-98298?

CVE-2026-98298 is a memory corruption vulnerability in Linux, published on 6 Oct 2026. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

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

dmaengine: mmp_pdma: fix wrong sg length in mmp_pdma_prep_slave_sg()

In mmp_pdma_prep_slave_sg(), for_each_sg() iterates the scatterlist
putting each entry into 'sg', but the entry length is read from 'sgl'
(the list head) instead of 'sg' (the current entry):

    for_each_sg(sgl, sg, sg_len, i) {
        addr = sg_dma_address(sg);
        avail = sg_dma_len(sgl);   /* should be 'sg' */

Consequently 'avail' is always the length of the first entry. For
multi-sg lists this causes out-of-bounds reads when a later entry is
shorter than the first, and silent data loss when it is longer.
Single-sg or uniformly-sized lists happen to mask the issue.

## Which versions are affected by CVE-2026-98298?


## How do I fix CVE-2026-98298?

Apply the vendor's patch.

## Is CVE-2026-98298 being exploited?

There is no known exploitation of CVE-2026-98298 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-98298 and fix it if it is affected.

What it is: CVE-2026-98298 is a memory corruption vulnerability in Linux, published on 6 Oct 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-98298 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-2026-98298/ (Markdown: https://insights.sbomify.com/CVE-2026-98298/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-98298
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-98298
- OSV: https://osv.dev/vulnerability/CVE-2026-98298

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-98298/
Summaries are generated and may contain mistakes; the official description above is the record.