---
cve: "CVE-2021-47288"
severity: "HIGH"
cvss: 7.1
epss: "0.2%"
vendor: "Linux"
kev: false
exploited: false
published: "2024-05-21 15:15:16"
tags: [cve, security, high]
source: tsecurity.de CVE-Dossier
exported: "2026-10-02T07:45:31+02:00"
---

# CVE-2021-47288

> 7.1 HIGH

## Beschreibung

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

media: ngene: Fix out-of-bounds bug in ngene_command_config_free_buf()

Fix an 11-year old bug in ngene_command_config_free_buf() while
addressing the following warnings caught with -Warray-bounds:

arch/alpha/include/asm/string.h:22:16: warning: '__builtin_memcpy' offset [12, 16] from the object at 'com' is out of the bounds of referenced subobject 'config' with type 'unsigned char' at offset 10 [-Warray-bounds]
arch/x86/include/asm/string_32.h:182:25: warning: '__builtin_memcpy' offset [12, 16] from the object at 'com' is out of the bounds of referenced subobject 'config' with type 'unsigned char' at offset 10 [-Warray-bounds]

The problem is that the original code is trying to copy 6 bytes of
data into a one-byte size member _config_ of the wrong structue
FW_CONFIGURE_BUFFERS, in a single call to memcpy(). This causes a
legitimate compiler warning because memcpy() overruns the length
of &com.cmd.ConfigureBuffers.config. It seems that the right
structure is FW_CONFIGURE_FREE_BUFFERS, instead, because it contains
6 more members apart from the header _hdr_. Also, the name of
the function ngene_command_config_free_buf() suggests that the actual
intention is to ConfigureFreeBuffers, instead of ConfigureBuffers
(which takes place in the function ngene_command_config_buf(), above).

Fix this by enclosing those 6 members of struct FW_CONFIGURE_FREE_BUFFERS
into new struct config, and use &com.cmd.ConfigureFreeBuffers.config as
the destination address, instead of &com.cmd.ConfigureBuffers.config,
when calling memcpy().

This also helps with the ongoing efforts to globally enable
-Warray-bounds and get us closer to being able to tighten the
FORTIFY_SOURCE routines on memcpy().

## CISA-Anreicherung (vulnrichment/ADP)

- CISA-SSVC (Coordinator, v2.0.3):
  - Exploitation: **none**
  - Automatable: **no**
  - Technical Impact: **partial**

## CVSS-Vektor

```
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H
```

| Metrik | Wert | Bewertung |
|---|---|---|
| AV Angriffsvektor | Lokal | good |
| AC Komplexität | Gering | bad |
| PR Privilegien | Gering | warn |
| UI Interaktion | Keine | bad |
| S Scope | Unverändert | good |
| C Vertraulichkeit | Hoch | bad |
| I Integrität | Keine | good |
| A Verfügbarkeit | Hoch | bad |

## Referenzen

- <https://git.kernel.org/stable/c/4487b968e5eacd02c493303dc2b61150bb7fe4b2>
- <https://git.kernel.org/stable/c/c6ddeb63dd543b5474b0217c4e47538b7ffd7686>
- <https://git.kernel.org/stable/c/e818f2ff648581a6c553ae2bebc5dcef9a8bb90c>
- <https://git.kernel.org/stable/c/ec731c6ef564ee6fc101fc5d73e3a3a953d09a00>
- <https://git.kernel.org/stable/c/e617fa62f6cf859a7b042cdd6c73af905ff8fca3>
- <https://git.kernel.org/stable/c/e991457afdcb5f4dbc5bc9d79eaf775be33e7092>
- <https://git.kernel.org/stable/c/b9a178f189bb6d75293573e181928735f5e3e070>
- <https://git.kernel.org/stable/c/8d4abca95ecc82fc8c41912fa0085281f19cc29f>

---
_Exportiert aus dem [tsecurity.de CVE-Dossier](https://tsecurity.de/cve?cve=CVE-2021-47288) · Datenquellen: EUVD (ENISA), NVD, OSV, CISA KEV, FIRST EPSS, Exploit-DB, BSI WID (CSAF)_
