Bug 2536234 (CVE-2026-93139)

Summary:	CVE-2026-93139 kernel: drm/amdgpu/mes: Fix hung_queue_db_array loop limit for multi-XCC
Product:	[Other] Security Response	Reporter:	OSIDB Bzimport <bzimport>
Component:	vulnerability	Assignee:	Product Security <prodsec-ir-bot>
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 AMDGPU driver within the Linux kernel. An issue with the `hung_queue_db_array` loop limit for multi-XCC (Cross-Chiplet Interconnect) GPUs can leave array entries uninitialized. This can lead to a null pointer dereference when accessing arrays indexed by XCC ID greater than or equal to 2, potentially causing a system crash or denial of service.	Story Points:	---
Clone Of:		Environment:
Last Closed:		Type:	---
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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 17:02:07 UTC

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

drm/amdgpu/mes: Fix hung_queue_db_array loop limit for multi-XCC

The loop iterated only AMDGPU_MAX_MES_PIPES times, leaving entries
uninitialized for multi-XCC GPUs. This causes null pointer dereferences
when accessing arrays indexed by XCC ID >= 2. Extend the loop to cover
all XCCs (AMDGPU_MAX_MES_PIPES * num_xcc), matching other per-XCC
arrays.

Comment 1 gkamathe 2026-09-18 19:06:13 UTC

Upstream advisory:
https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-93139.mbox