Bug 2513207 (CVE-2026-68240)

Summary:	CVE-2026-68240 kernel: drm/gpusvm: publish dpagemap early to avoid device mapping leak on error
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 drm/gpusvm component. When drm_gpusvm_get_pages() encounters an error during page mapping, it fails to properly unmap previously created device mappings. This oversight can lead to a device mapping leak, consuming system resources and potentially impacting system stability or performance over time.	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 12:24:55 UTC

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

drm/gpusvm: publish dpagemap early to avoid device mapping leak on error

drm_gpusvm_get_pages() only stored the local dpagemap into
svm_pages->dpagemap on the success path. If a later page failed (e.g.
-EOPNOTSUPP when ctx->allow_mixed is false) and jumped to err_unmap,
svm_pages->dpagemap was still NULL, so __drm_gpusvm_unmap_pages() skipped
device_unmap() and leaked the device mappings already created.

Assign svm_pages->dpagemap when the first device page is mapped so the
err_unmap path can device_unmap() those mappings.

This issue was found by Sashiko AI review.