Bug 2541259 (CVE-2026-98004)

Summary:	CVE-2026-98004 kernel: iommu/riscv: Serialize command queue publishing
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 RISC-V IOMMU (Input-Output Memory Management Unit) driver. A local user can exploit this vulnerability to cause a Denial of Service (DoS) on systems running RISC-V architecture. A concurrency issue in how commands are published to the hardware queue allows lock contention to block other processor cores, resulting in a system hang.	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 2026-09-25 11:11:34 UTC

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

iommu/riscv: Serialize command queue publishing

Serialize command queue publishing so software producer state advances only
after a command is written and the hardware tail is updated. Wait for
hardware consumption outside the queue lock when the command queue is full
so other CPUs are not blocked behind a long poll.

Comment 1 Keith Grant 2026-09-28 18:47:07 UTC

Upstream advisory:
https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-98004.mbox