CVE-2023-52736: ALSA: hda: Do not unset preset when cleaning up codec

Description

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

ALSA: hda: Do not unset preset when cleaning up codec

Several functions that take part in codec's initialization and removal
are re-used by ASoC codec drivers implementations. Drivers mimic the
behavior of hda_codec_driver_probe/remove() found in
sound/pci/hda/hda_bind.c with their component->probe/remove() instead.

One of the reasons for that is the expectation of
snd_hda_codec_device_new() to receive a valid pointer to an instance of
struct snd_card. This expectation can be met only once sound card
components probing commences.

As ASoC sound card may be unbound without codec device being actually
removed from the system, unsetting ->preset in
snd_hda_codec_cleanup_for_unbind() interferes with module unload -> load
scenario causing null-ptr-deref. Preset is assigned only once, during
device/driver matching whereas ASoC codec driver's module reloading may
occur several times throughout the lifetime of an audio stack.

Classification

CVE ID: CVE-2023-52736

Affected Products

Vendor: Linux

Product: Linux

Exploit Prediction Scoring System (EPSS)

EPSS Score: 0.05% (probability of being exploited)

EPSS Percentile: 17.81% (scored less or equal to compared to others)

EPSS Date: 2025-02-03 (when was this score calculated)

References

https://git.kernel.org/stable/c/7fc4e7191eae9d9325511e03deadfdb2224914f8
https://git.kernel.org/stable/c/e909f5f2aa55a8f9aa6919cce08015cb0e8d4668
https://git.kernel.org/stable/c/427ca2530da8dc61a42620d7113b05e187b6c2c0
https://git.kernel.org/stable/c/87978e6ad45a16835cc58234451111091be3c59a

Timeline