Bug 2507038 (CVE-2026-64481)

Summary:	CVE-2026-64481 kernel: ALSA: hda/cs35l41: Fix firmware load work teardown
Product:	[Other] Security Response	Reporter:	OSIDB Bzimport <bzimport>
Component:	vulnerability	Assignee:	Product Security DevOps Team <prodsec-dev>
Status:	NEW ---	QA Contact:
Severity:	medium	Docs Contact:
Priority:	medium
Version:	unspecified	CC:	rhel-process-autobot, watson-tool-maintainers
Target Milestone:	---	Keywords:	Security
Target Release:	---
Hardware:	All
OS:	Linux
Whiteboard:
Fixed In Version:		Doc Type:	---
Doc Text:	A flaw was found in the Linux kernel's ALSA sound driver for the cs35l41 component. This vulnerability occurs because the driver fails to properly remove controls and cancel firmware load work during component unbinding or device removal, especially when firmware autostart is disabled. This can lead to a worker attempting to access driver data that is no longer valid after teardown, resulting in memory corruption. An attacker with local access could potentially exploit this to cause a denial of service or escalate privileges.	Story Points:	---
Clone Of:		Environment:
Last Closed:		Type:	---
Regression:	---	Mount Type:	---
Documentation:	---	CRM:
Verified Versions:		Category:	---
oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:
Embargoed:

Description OSIDB Bzimport 2026-07-25 10:01:47 UTC

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

ALSA: hda/cs35l41: Fix firmware load work teardown

cs35l41_hda creates ALSA controls whose private data points at the
cs35l41_hda object. The firmware load control can also queue
fw_load_work.

Those controls are not removed on component unbind, and device remove
only cancels fw_load_work through cs35l41_remove_dsp(). That helper is
skipped when halo_initialized is false. With firmware_autostart
disabled, a firmware load can be requested before the DSP has been
initialized. If the component or device is removed before the queued
work runs, the worker can run after teardown and dereference driver
state that is no longer valid.

Track the created controls and remove them on unbind so no new control
callback can reach the driver data or queue more work. Then cancel
fw_load_work to drain any request that was already queued. Also cancel
the work unconditionally during device remove before runtime PM teardown.

Comment 1 Mauro Matteo Cascella 2026-07-28 16:15:28 UTC

Upstream advisory:
https://lore.kernel.org/linux-cve-announce/2026072548-CVE-2026-64481-d8df@gregkh/T