Bug 2513333 (CVE-2026-68241)

Summary:	CVE-2026-68241 kernel: drm/i915/mst: limit DP MST ESI service loop
Product:	[Other] Security Response	Reporter:	OSIDB Bzimport <bzimport>
Component:	vulnerability	Assignee:	Product Security <prodsec-ir-bot>
Status:	NEW ---	QA Contact:
Severity:	low	Docs Contact:
Priority:	low
Version:	unspecified	CC:	rhel-process-autobot, 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 DisplayPort Multi-Stream Transport (MST) subsystem. An unbounded loop in the `intel_dp_check_mst_status()` function, responsible for servicing interrupts from a sink device, can lead to a system becoming unresponsive. A malicious or faulty DisplayPort MST sink device could exploit this to trigger a Denial of Service (DoS) condition.	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 2026-08-10 12:31:32 UTC

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

drm/i915/mst: limit DP MST ESI service loop

The loop in intel_dp_check_mst_status() keeps servicing interrupts
originating from the sink without bound. Add an upper bound to the new
interrupts occurring during interrupt processing to not get stuck on
potentially stuck sink devices. Use arbitrary 32 tries to clear incoming
interrupts in one go.

Discovered using AI-assisted static analysis confirmed by Intel Product
Security.

Note: The condition likely pre-dates the commit in the Fixes: tag, but
this is about as far back as a backport has any chance of
succeeding. Before that, the retry had a goto.

(cherry picked from commit b4ea5272133059acb493cc36599071a9e852ec2e)