CVE-2023-53275 ALSA: hda: fix a possible null-pointer dereference due to data race in snd_hdac_regmap_sync()

What is CVE-2023-53275?

CVE-2023-53275 is a medium-severity vulnerability in Linux kernel, published on 16 Sep 2025. 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:

ALSA: hda: fix a possible null-pointer dereference due to data race in snd_hdac_regmap_sync()

The variable codec->regmap is often protected by the lock codec->regmap_lock when is accessed. However, it is accessed without holding the lock when is accessed in snd_hdac_regmap_sync():

if (codec->regmap)

In my opinion, this may be a harmful race, because if codec->regmap is set to NULL right after the condition is checked, a null-pointer dereference can occur in the called function regcache_sync():

map->lock(map->lock_arg); --> Line 360 in drivers/base/regmap/regcache.c

To fix this possible null-pointer dereference caused by data race, the mutex_lock coverage is extended to protect the if statement as well as the function call to regcache_sync().

[ Note: the lack of the regmap_lock itself is harmless for the current codec driver implementations, as snd_hdac_regmap_sync() is only for PM runtime resume that is prohibited during the codec probe. But the change makes the whole code more consistent, so it's merged as is -- tiwai ]

Weakness: CWE-476

Which versions are affected by CVE-2023-53275?

It affects 1 product.

Products include Linux kernel.

How do I fix CVE-2023-53275?

Apply the vendor's patch.

Is CVE-2023-53275 being exploited?

There is no known exploitation of CVE-2023-53275 in the wild and no public exploit code.

Other vulnerabilities in Linux kernel

• CVE-2026-53266 Linux Kernel Out-of-Bounds Write Exploited High 8.8
• CVE-2013-6282 Linux Kernel Improper Input Validation Exploited High 8.8
• CVE-2022-0185 Linux Kernel Heap-Based Buffer Overflow Exploited High 8.4
• CVE-2013-2094 Linux Kernel Privilege Escalation Exploited High 8.4
• CVE-2026-53362 Linux Kernel Unspecified Exploited High 7.8

All Linux kernel vulnerabilities

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as BELL-CVE-2023-53275, DEBIAN-CVE-2023-53275, GHSA-m34j-mgrv-w6rc, UBUNTU-CVE-2023-53275.