In the Linux kernel ASoC subsystem the fsl_micfil driver contains a logic flaw where the hardware parameters routine enables the master clock (mclk) without checking its current status, and the corresponding free routine disables it unconditionally. Because these two callbacks are not guaranteed to be called in a 1:1 sequence, a call to hw_free() can occur without a preceding hw_params() and an hw_params() can be invoked repeatedly during the SETUP state. The first scenario triggers a WARN() as the clock is already disabled, while the second scenario leaks an enable reference, causing the clock to remain enabled and ungateable. This resource leak can prevent proper shutdown of the audio hardware and may degrade system stability, effectively serving as a denial‑of‑service vector.

Affected systems encompass Linux kernel installations that include the fsl_micfil ASoC driver, which is common in certain ARM SoC configurations. No specific kernel version ranges are provided, so all kernel releases with this driver prior to the fix may be vulnerable.

The EPSS score for this issue is not available and the vulnerability is not listed in the CISA KEV catalog, suggesting that no public exploit is known. Nonetheless the bug can be triggered locally by applications that exercise the PCM audio subsystem and could lead to a steady resource leak of the master clock, causing intermittent or permanent loss of audio capability. Because the fault requires code paths within the kernel and no remote exploitation vector is documented, the overall risk remains moderate, though the impact on availability warrants prompt attention if affected hardware is in use.