CVE-2025-38078

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

ALSA: pcm: Fix race of buffer access at PCM OSS layer

The PCM OSS layer tries to clear the buffer with the silence data at

initialization (or reconfiguration) of a stream with the explicit call

of snd_pcm_format_set_silence() with runtime->dma_area. But this may

lead to a UAF because the accessed runtime->dma_area might be freed

concurrently, as it's performed outside the PCM ops.

For avoiding it, move the code into the PCM core and perform it inside

the buffer access lock, so that it won't be changed during the

operation.