Bug 2546430 (CVE-2026-98212)

Summary:	CVE-2026-98212 kernel: mmc: hsq: Fix use-after-free in retry work
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 MultiMediaCard (MMC) host software queue. A local user could exploit a use-after-free vulnerability when pending retry operations are not cancelled before device removal, allowing tasks to access memory after it has been released. This issue can lead to a Denial of Service (DoS) through a system crash or potential privilege escalation.	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 2026-10-06 09:19:43 UTC

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

mmc: hsq: Fix use-after-free in retry work

mmc_hsq_pump_requests() queues retry_work when request_atomic() returns
-EBUSY; today sdhci-sprd is the only consumer that implements
request_atomic(). The work is embedded in a devm-allocated mmc_hsq, but
is never cancelled during driver removal. Work still pending at unbind
can therefore run after the devm allocation has been released and
dereference hsq->mmc and hsq->mrq.

Use devm_work_autocancel() to cancel and drain retry_work before the devm
allocation is released. By the time devres cleanup begins,
mmc_remove_host() has already stopped the host, so no new requests can
arm the work.

This issue was found by an in-house static analysis tool.

Comment 1 Mauro Matteo Cascella 2026-10-09 09:28:41 UTC

Upstream advisory:
https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-98212.mbox