# CVE-2021-47535: drm/msm/a6xx: Allocate enough space for GMU registers

> A memory corruption vulnerability in the Linux kernel's MSM GPU driver allows a local attacker to cause a system crash via out-of-bounds write.

- **Severity:** High 7.8 (`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H`)
- **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:** 24 May 2024
- **Updated:** 5 Aug 2026
- **Also known as:** DEBIAN-CVE-2021-47535, UBUNTU-CVE-2021-47535

## What is CVE-2021-47535?

CVE-2021-47535 is a high-severity memory corruption vulnerability in Linux kernel, published on 24 May 2024. 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/msm/a6xx: Allocate enough space for GMU registers

In commit 142639a52a01 ("drm/msm/a6xx: fix crashstate capture for
A650") we changed a6xx_get_gmu_registers() to read 3 sets of
registers. Unfortunately, we didn't change the memory allocation for
the array. That leads to a KASAN warning (this was on the chromeos-5.4
kernel, which has the problematic commit backported to it):

  BUG: KASAN: slab-out-of-bounds in _a6xx_get_gmu_registers+0x144/0x430
  Write of size 8 at addr ffffff80c89432b0 by task A618-worker/209
  CPU: 5 PID: 209 Comm: A618-worker Tainted: G        W         5.4.156-lockdep #22
  Hardware name: Google Lazor Limozeen without Touchscreen (rev5 - rev8) (DT)
  Call trace:
   dump_backtrace+0x0/0x248
   show_stack+0x20/0x2c
   dump_stack+0x128/0x1ec
   print_address_description+0x88/0x4a0
   __kasan_report+0xfc/0x120
   kasan_report+0x10/0x18
   __asan_report_store8_noabort+0x1c/0x24
   _a6xx_get_gmu_registers+0x144/0x430
   a6xx_gpu_state_get+0x330/0x25d4
   msm_gpu_crashstate_capture+0xa0/0x84c
   recover_worker+0x328/0x838
   kthread_worker_fn+0x32c/0x574
   kthread+0x2dc/0x39c
   ret_from_fork+0x10/0x18

  Allocated by task 209:
   __kasan_kmalloc+0xfc/0x1c4
   kasan_kmalloc+0xc/0x14
   kmem_cache_alloc_trace+0x1f0/0x2a0
   a6xx_gpu_state_get+0x164/0x25d4
   msm_gpu_crashstate_capture+0xa0/0x84c
   recover_worker+0x328/0x838
   kthread_worker_fn+0x32c/0x574
   kthread+0x2dc/0x39c
   ret_from_fork+0x10/0x18

Weakness: CWE-787 (Out-of-bounds Write)

## Which versions are affected by CVE-2021-47535?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2021-47535?

Apply the vendor's patch.

## Is CVE-2021-47535 being exploited?

There is no known exploitation of CVE-2021-47535 in the wild and no public exploit code.

## Other vulnerabilities in Linux kernel

- [CVE-2026-53266](https://insights.sbomify.com/CVE-2026-53266/): Linux Kernel Out-of-Bounds Write (high 8.8, exploited in the wild)
- [CVE-2013-6282](https://insights.sbomify.com/CVE-2013-6282/): Linux Kernel Improper Input Validation (high 8.8, exploited in the wild)
- [CVE-2022-0185](https://insights.sbomify.com/CVE-2022-0185/): Linux Kernel Heap-Based Buffer Overflow (high 8.4, exploited in the wild)
- [CVE-2013-2094](https://insights.sbomify.com/CVE-2013-2094/): Linux Kernel Privilege Escalation (high 8.4, exploited in the wild)
- [CVE-2026-53362](https://insights.sbomify.com/CVE-2026-53362/): Linux Kernel Unspecified (high 7.8, exploited in the wild)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2021-47535 and fix it if it is affected.

What it is: CVE-2021-47535 is a high-severity memory corruption vulnerability in Linux kernel, published on 24 May 2024. 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-2021-47535 in the wild and no public exploit code.

Affected product: Linux kernel. 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-2021-47535/ (Markdown: https://insights.sbomify.com/CVE-2021-47535/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2021-47535
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2021-47535
- OSV: https://osv.dev/vulnerability/CVE-2021-47535

---
From sbomify Insights: https://insights.sbomify.com/CVE-2021-47535/
Summaries are generated and may contain mistakes; the official description above is the record.