Bug 2468204 (CVE-2026-43351)

Summary:	CVE-2026-43351 kernel: KVM: arm64: Eagerly init vgic dist/redist on vgic creation
Product:	[Other] Security Response	Reporter:	OSIDB Bzimport <bzimport>
Component:	vulnerability	Assignee:	Product Security DevOps Team <prodsec-dev>
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 Kernel-based Virtual Machine (KVM) for arm64 architectures. When a virtual Generic Interrupt Controller (GIC) is created, a failure in the `vgic_allocate_private_irqs_locked()` function can leave internal data structures uninitialized. This can lead to a system crash when the KVM module attempts to free these uninitialized regions, resulting in a denial of service.	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 2026-05-08 15:04:37 UTC

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

KVM: arm64: Eagerly init vgic dist/redist on vgic creation

If vgic_allocate_private_irqs_locked() fails for any odd reason,
we exit kvm_vgic_create() early, leaving dist->rd_regions uninitialised.

kvm_vgic_dist_destroy() then comes along and walks into the weeds
trying to free the RDs. Got to love this stuff.

Solve it by moving all the static initialisation early, and make
sure that if we fail halfway, we're in a reasonable shape to
perform the rest of the teardown. While at it, reset the vgic model
on failure, just in case...

Comment 1 Keith Grant 2026-05-08 19:48:36 UTC

Upstream advisory:
https://lore.kernel.org/linux-cve-announce/2026050820-CVE-2026-43351-da54@gregkh/T