CVE-2026-80828

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

ALSA: usb-audio: Complete cleanup after system-resume errors

A failed system resume can leave the card unusable until reboot. usb audio resume() jumps to err out when snd usb pcm resume() or snd usb mixer resume() fails. The error path skips the out: block, which restores D0 and decrements chip->num suspended intf.

The card stays in SNDRV CTL POWER D3hot, so later control access blocks in snd power ref and wait(). USB core logs an interface resume callback error. It does not retry that callback, so a later callback cannot complete the skipped cleanup.

usb audio suspend() increments num suspended intf before returning success. A system-resume callback must consume the system-suspend count even if a component resume fails. Otherwise, the stranded count skews later suspend and resume cycles.

Do not apply this cleanup to runtime-resume errors. Runtime PM can retry -EAGAIN or -EBUSY without another suspend callback. The count must continue to describe that suspended interface. Other runtime-resume errors latch runtime error in the PM core and do not cause an immediate callback retry.

Both parts of the system-resume error path are longstanding. Commit 88a8516a2128a ("ALSA: usbaudio: implement USB autosuspend") introduced err out past the D0 restore. Commit 862b2509d157c ("ALSA: usb-audio: Fix inconsistent card PM state after resume") later moved num suspended intf-- into the out: block. The error path now skips both operations.

No third-party code is needed to reach the error path. snd usb mixer resume() ends in snd usb mixer activate(), which returns the result of usb submit urb() for devices that have a mixer status URB. Its mixer->private resume hook can also fail through scarlett2 init notify(). snd usb pcm resume() issues a SET CUR request to a UAC3 power domain. It can return -EPIPE or -EIO when the device stalls the request.

Route a component error through out: only when system suspend is nonzero. Continue to return runtime-resume errors through err out. Later component resume stages remain skipped. The original error still reaches USB core. A later transfer can fail if the device did not recover.

I reproduced the system-resume failure on an Audient iD14 MkI with an out-of-tree diagnostic mixer resume hook. An injected -EIO on the unpatched core left control readers in uninterruptible sleep in snd power ref and wait() until a reboot. With this patch, the same failure restored control access. A second system suspend and resume also succeeded after I disabled fault injection.