Bug 2451231 (CVE-2026-23338)

Summary:	CVE-2026-23338 kernel: drm/amdgpu/userq: Do not allow userspace to trivially triger kernel warnings
Product:	[Other] Security Response	Reporter:	OSIDB Bzimport <bzimport>
Component:	vulnerability	Assignee:	Product Security <prodsec-ir-bot>
Status:	NEW ---	QA Contact:
Severity:	unspecified	Docs Contact:
Priority:	unspecified
Version:	unspecified	Keywords:	Security
Target Milestone:	---
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Hardware:	All
OS:	Linux
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Doc Text:	A flaw was found in the Linux kernel, specifically within the `drm/amdgpu/userq` component. This vulnerability allows a local user to intentionally or unintentionally trigger kernel warnings. This occurs when the user provides an incorrect number of fences during a `userq wait ioctl` operation. While this does not compromise the kernel's integrity, it can lead to unnecessary system diagnostic messages.	Story Points:	---
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oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:
Embargoed:

Description OSIDB Bzimport 2026-03-25 11:06:00 UTC

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

drm/amdgpu/userq: Do not allow userspace to trivially triger kernel warnings

Userspace can either deliberately pass in the too small num_fences, or the
required number can legitimately grow between the two calls to the userq
wait ioctl. In both cases we do not want the emit the kernel warning
backtrace since nothing is wrong with the kernel and userspace will simply
get an errno reported back. So lets simply drop the WARN_ONs.

(cherry picked from commit 2c333ea579de6cc20ea7bc50e9595ef72863e65c)

Comment 1 Alexander B 2026-03-25 14:30:36 UTC

Upstream advisory:
https://lore.kernel.org/linux-cve-announce/2026032534-CVE-2026-23338-67c7@gregkh/T