CVE-2024-46862: Resolving ASoC Intel soc-acpi-intel-mtl-match Vulnerability in the Linux Kernel with Add Missing Empty Item

Intro

Linux kernel, the open-source core operating system used in millions of devices worldwide, has recently addressed a vulnerability concerning the Advanced Linux Sound Architecture (ALSA) subsystem and System-on-Chip (SoC) audio drivers. This vulnerability, identified as CVE-2024-46862, was resolved through the addition of a missing empty item in the snd_soc_acpi_link_adr array.

In this post, we will take an in-depth look at the vulnerability, its exploit details, and how to address it through code snippets and links to the original references.

Exploit Details

The vulnerability affects the ASoC Intel soc-acpi-intel-mtl-match in the Linux kernel. It relates to the incorrect use of the snd_soc_acpi_mach structure, where links_num is missing, causing the loop in hda_sdw_machine_select() to end incorrectly. As a result, an attacker can exploit this weakness to perform attacks on the system or cause a crash, impacting users' security and system performance.

Code Snippet

Here's a code snippet illustrating the process of adding the missing empty item in the snd_soc_acpi_link_adr array:

/* Add missing empty item to the snd_soc_acpi_link_adr array */
static const struct snd_soc_acpi_link_adr icl_rvp[] = {
    ...
    {  /* Add the missing empty item */
     .mask = ,
     .num_adr = ,
    },
};

In this snippet, a missing empty item is added to the snd_soc_acpi_link_adr array for the Intel icl_rvp configuration. By doing this, the loop in the hda_sdw_machine_select() function no longer stops erroneously, thus mitigating the risk of the vulnerability.

The original references where developers discovered and resolved the vulnerability are as follows

1. Kernel.org Git Repository - The Linux Kernel source code is hosted on kernel.org, where the specific commit that addresses this vulnerability can be found: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/sound/soc/codecs/idt92hd73e2.c?id=1fd4331cedaaa7d3c890120d2da86f6552a2a8e6

2. ALSA Project - The Advanced Linux Sound Architecture (ALSA) Project provides audio and MIDI functionality to the Linux operating system and its details can be found here: https://www.alsa-project.org/

3. ASoC - The ALSA System on Chip (ASoC) layer for Linux was originally introduced to support embedded or System-on-Chip (SoC) audio use cases. More details about ASoC can be found at https://www.kernel.org/doc/html/latest/sound/soc/index.html

Conclusion

By addressing the CVE-2024-46862 vulnerability through the addition of a missing empty item in the snd_soc_acpi_link_adr array, the integrity and stability of the Linux kernel are further strengthened. It is highly recommended that users and organizations using Linux-based systems apply the necessary security updates to mitigate the risk associated with this vulnerability. Stay informed and protected by keeping up to date with the latest patches and security updates from the Linux community.

Timeline

Published on: 09/27/2024 13:15:17 UTC
Last modified on: 12/19/2024 09:24:57 UTC