CVE-2026-80716

/// Technical description

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

ALSA: pcm: wake linked drain waiters on unlink

snd_pcm_drain() on a linked stream parks an on-stack wait entry on the

drained peer's runtime->sleep, and after schedule_timeout() removes it

only if that peer is still found in the caller's group. If group

membership changes during the wait and the sleep ends by signal or

timeout (so autoremove_wake_function() does not run), finish_wait() is

skipped and snd_pcm_drain() returns with the entry still queued on that

stream's sleep list; a later wake_up() then walks a freed stack frame.

This is reachable by unlinking either the drained or the draining stream.

Unlike the close path (snd_pcm_drop() -> snd_pcm_post_stop()),

snd_pcm_unlink() never wakes the sleep queues. Wake every group member

under the group lock before the membership change, so a linked drainer is

released and drops its entry while the streams are still grouped.

The window was opened when snd_pcm_link_rws

/// Remediation

Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.

/// References