Bug 2460622 (CVE-2026-31440)

Summary:	CVE-2026-31440 kernel: Linux kernel: Denial of Service due to event log memory leak in dmaengine: idxd
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:	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 dmaengine: idxd component. This vulnerability occurs during the device removal process, where a race condition can lead to event log memory not being properly deallocated if the device is reset before the deallocation check. A local attacker could exploit this memory leak, potentially leading to a denial of service (DoS) on the system.	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 2026-04-22 15:01:44 UTC

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

dmaengine: idxd: Fix leaking event log memory

During the device remove process, the device is reset, causing the
configuration registers to go back to their default state, which is
zero. As the driver is checking if the event log support was enabled
before deallocating, it will fail if a reset happened before.

Do not check if the support was enabled, the check for 'idxd->evl'
being valid (only allocated if the HW capability is available) is
enough.

Comment 1 Keith Grant 2026-04-22 17:05:32 UTC

Upstream advisory:
https://lore.kernel.org/linux-cve-announce/2026042244-CVE-2026-31440-78bd@gregkh/T