# CVE-2026-97551: xfs: initialise args->total for parent pointer updates

> An integer overflow in XFS parent pointer updates causes filesystem shutdown, leading to denial of service for local attackers.

- **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:** 25 Sep 2026
- **Updated:** 19 Oct 2026
- **Also known as:** BELL-CVE-2026-97551, DEBIAN-CVE-2026-97551, GHSA-hph3-hwfc-67wh, UBUNTU-CVE-2026-97551

## What is CVE-2026-97551?

CVE-2026-97551 is a vulnerability in Linux, published on 25 Sep 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:

xfs: initialise args->total for parent pointer updates

xfs_parent_da_args_init() builds an xfs_da_args from a zeroed
xfs_parent_args (kmem_cache_zalloc), leaving args->total == 0.
xfs_da_grow_inode_int() treats that field as a running block reservation
and subtracts from it; because it is an xfs_extlen_t (uint32_t), the
first attr-fork growth wraps it to ~0U.  That defeats the free-space
check in xfs_alloc_space_available(), and when it coincides with an AG
that has exactly zero available blocks the allocation is clamped to
maxlen 0 and returns -ENOSPC, which xfs_defer_finish_noroll() escalates
to a filesystem shutdown.

Set args->total the way the log recovery path does
(xfs_attri_recover_work(), xfs_attr_item.c:706), in the add and replace
paths that can grow the fork.  Removals and lookups never grow it, so
they leave the field alone, matching that switch.

## Which versions are affected by CVE-2026-97551?


## How do I fix CVE-2026-97551?

Apply the vendor's patch.

## Is CVE-2026-97551 being exploited?

There is no known exploitation of CVE-2026-97551 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-97551 and fix it if it is affected.

What it is: CVE-2026-97551 is a vulnerability in Linux, published on 25 Sep 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-2026-97551 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-2026-97551/ (Markdown: https://insights.sbomify.com/CVE-2026-97551/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-97551
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-97551
- OSV: https://osv.dev/vulnerability/CVE-2026-97551

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-97551/
Summaries are generated and may contain mistakes; the official description above is the record.