CVE-2026-43351: KVM: arm64: Eagerly init vgic dist/redist on vgic creation

CVE-2026-43351: KVM: arm64: Eagerly init vgic dist/redist on vgic creation

[Greg Kroah-Hartman]

From: Greg Kroah-Hartman <gregkh@kernel.org>

Description
===========

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...

The Linux kernel CVE team has assigned CVE-2026-43351 to this issue.


Affected and fixed versions
===========================

	Issue introduced in 6.14 with commit b3aa9283c0c505b5cfd25f7d6cfd720de2adc807 and fixed in 6.18.19 with commit b7493f48c3dba75674a4ee505b4afa8fe5102457
	Issue introduced in 6.14 with commit b3aa9283c0c505b5cfd25f7d6cfd720de2adc807 and fixed in 6.19.9 with commit a24f1d80fbcdbf8b2a7044a00fa12b3972b4c31c
	Issue introduced in 6.14 with commit b3aa9283c0c505b5cfd25f7d6cfd720de2adc807 and fixed in 7.0 with commit ac6769c8f948dff33265c50e524aebf9aa6f1be0

Please see https://www.kernel.org for a full list of currently supported
kernel versions by the kernel community.

Unaffected versions might change over time as fixes are backported to
older supported kernel versions.  The official CVE entry at
	https://cve.org/CVERecord/?id=CVE-2026-43351
will be updated if fixes are backported, please check that for the most
up to date information about this issue.


Affected files
==============

The file(s) affected by this issue are:
	arch/arm64/kvm/vgic/vgic-init.c


Mitigation
==========

The Linux kernel CVE team recommends that you update to the latest
stable kernel version for this, and many other bugfixes.  Individual
changes are never tested alone, but rather are part of a larger kernel
release.  Cherry-picking individual commits is not recommended or
supported by the Linux kernel community at all.  If however, updating to
the latest release is impossible, the individual changes to resolve this
issue can be found at these commits:
	https://git.kernel.org/stable/c/b7493f48c3dba75674a4ee505b4afa8fe5102457
	https://git.kernel.org/stable/c/a24f1d80fbcdbf8b2a7044a00fa12b3972b4c31c
	https://git.kernel.org/stable/c/ac6769c8f948dff33265c50e524aebf9aa6f1be0