# CVE-2026-63880: drm/amdgpu: fix lock leak on ENOMEM in AMDGPU_GEM_OP_GET_MAPPING_INFO

> A local attacker with GPU access can trigger a lock leak in the AMDGPU driver, causing a denial of service by blocking subsequent GPU operations.

- **Severity:** Not scored
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 19 Jul 2026
- **Updated:** 19 Jul 2026
- **Also known as:** BELL-CVE-2026-63880, DEBIAN-CVE-2026-63880, GHSA-5vfp-rcpc-cr39, UBUNTU-CVE-2026-63880

## What is CVE-2026-63880?

CVE-2026-63880 is a denial of service vulnerability in Linux, published on 19 Jul 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:

drm/amdgpu: fix lock leak on ENOMEM in AMDGPU_GEM_OP_GET_MAPPING_INFO

The AMDGPU_GEM_OP_GET_MAPPING_INFO branch of amdgpu_gem_op_ioctl()
holds three cleanup-tracked resources before calling kvcalloc():
the drm_gem_object reference from drm_gem_object_lookup(), the
drm_exec lock on the looked-up GEM via drm_exec_lock_obj(), and
the drm_exec lock on the per-process VM root page directory via
amdgpu_vm_lock_pd().  All three are released by the out_exec
label that every other error path in this function jumps to.
The kvcalloc() failure path returns -ENOMEM directly, skipping
out_exec and leaking all three.

The leaked per-process VM root PD dma_resv lock is the
load-bearing leak: any subsequent operation on the same VM
(further GEM ops, command-submission, eviction, TTM shrinker
callbacks) blocks on the held lock.  DRM_IOCTL_AMDGPU_GEM_OP is
DRM_AUTH | DRM_RENDER_ALLOW, so this is an unprivileged-local
denial of service against the caller's GPU context, reachable
by any process with /dev/dri/renderD* access.

Route the failure through out_exec so drm_exec_fini() and
drm_gem_object_put() run.

Reproduced on stock 7.0.0-10, Ryzen 7 5700U / Radeon Vega
(Lucienne): the failing ioctl returns -ENOMEM and a second
GET_MAPPING_INFO on the same fd then blocks in
drm_exec_lock_obj() on the leaked dma_resv.  SIGKILL on the
caller does not reap the task; the fd-release path during
process exit goes through amdgpu_gem_object_close() ->
drm_exec_prepare_obj() on the same lock, leaving the task in D
state until the box is rebooted.  The patched kernel was not
rebuilt and re-tested on this hardware; the fix is mechanical.
Tested on a single Lucienne / Vega box only.

Ziyi Guo posted an independent INT_MAX-bound check for
args->num_entries in the same branch [1]; the two patches are
complementary and can land in either order.

(cherry picked from commit b69d3256d79de15f54c322986ff4da68f1d65b0a)

## Which versions are affected by CVE-2026-63880?


## How do I fix CVE-2026-63880?

Apply the vendor's patch.

## Is CVE-2026-63880 being exploited?

There is no known exploitation of CVE-2026-63880 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-63880 and fix it if it is affected.

What it is: CVE-2026-63880 is a denial of service vulnerability in Linux, published on 19 Jul 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-2026-63880 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-2026-63880/ (Markdown: https://insights.sbomify.com/CVE-2026-63880/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-63880
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-63880
- OSV: https://osv.dev/vulnerability/CVE-2026-63880

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-63880/
Summaries are generated and may contain mistakes; the official description above is the record.