# GSD-2021-1001215: dm btree remove: assign new_root only when removal succeeds

> A logic error in the Linux kernel device-mapper btree removal could lead to a null pointer dereference and system crash.

- **Severity:** Not scored
- **Exploited in the wild:** Not known
- **Login needed:** Not stated
- **Attackable:** Not stated
- **Victim action needed:** Not stated
- **Fix available:** No
- **Published:** 3 Aug 2021

## What is GSD-2021-1001215?

GSD-2021-1001215 is a vulnerability in Kernel, published on 3 Aug 2021. 

### Official description

dm btree remove: assign new_root only when removal succeeds

This is an automated ID intended to aid in discovery of potential security vulnerabilities. The actual impact and attack plausibility have not yet been proven.
This ID is fixed in Linux Kernel version v5.13.3 by commit ad365e9351ac2b450e7e79932ff6abf59342d91a. For more details please see the references link.

## Which versions are affected by GSD-2021-1001215?

1 open source package ship an affected version, including Kernel.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `Kernel` | Linux | All versions | None |

## How do I fix GSD-2021-1001215?

No fix has been published for GSD-2021-1001215 yet. Limit exposure of the affected software until one is available.

## Is GSD-2021-1001215 being exploited?

There is no known exploitation of GSD-2021-1001215 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for GSD-2021-1001215 and fix it if it is affected.

What it is: GSD-2021-1001215 is a vulnerability in Kernel, published on 3 Aug 2021. 
Exploitation: There is no known exploitation of GSD-2021-1001215 in the wild and no public exploit code.

Affected packages and fixed versions:
- Kernel (Linux): affected all versions; no fix listed

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/GSD-2021-1001215/ (Markdown: https://insights.sbomify.com/GSD-2021-1001215/index.md)
```

## Sources

- OSV: https://osv.dev/vulnerability/GSD-2021-1001215

---
From sbomify Insights: https://insights.sbomify.com/GSD-2021-1001215/
Summaries are generated and may contain mistakes; the official description above is the record.