Bug 2536485 (CVE-2026-90296)

Summary:	CVE-2026-90296 kernel: cpufreq: imx6q: fix devres accumulation across driver rebind
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:	akhatavk, aos-team-art-private, asdas, dpaolell, jdelft, jupierce, lgarciaa, mbiarnes, ppalepu, ppostler, prdhamdh, rhel-process-autobot, sghai, sidsharm, suppawar, vlaad, 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 `cpufreq: imx6q` driver. This vulnerability involves improper management of device resources when the driver is reloaded or re-initialized. Repeated reloads can lead to a continuous accumulation of memory, which is not properly released. This memory leak could eventually cause the system to become unstable or unresponsive, leading to a denial of service.	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 2026-09-17 18:10:24 UTC

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

cpufreq: imx6q: fix devres accumulation across driver rebind

imx6_soc_volt is allocated with devm_kcalloc(cpu_dev, ...), where cpu_dev
is the CPU device from get_cpu_device(0). That device is never unbound, so
its devres list is never released, and imx6q_cpufreq_remove() does not free
the array either. Every probe therefore adds an allocation that stays for
the lifetime of the system.

Allocate against the platform device instead. Its devres is released when
the driver is unbound, which is exactly the lifetime the array wants:
imx6q_set_target() reads it, and nothing may reach that after
cpufreq_unregister_driver().

That makes the array actually go away on unbind, so also clear the
file-scope pointer in remove and on the failed-probe path, rather than
leave it pointing at memory devres is about to release.

Tested by rebinding the driver on qemu's mcimx6ul-evk.

Comment 1 gkamathe 2026-09-22 20:10:15 UTC

Upstream advisory:
https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-90296.mbox