---
id: CVE-2026-98470
title: 'KVM: arm64: Don''t WARN on an unknown VM ioctl in protected mode'
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  KVM: arm64: Don't WARN on an unknown VM ioctl in protected mode

  kvm_pkvm_ioctl_allowed() WARNs when kvm_get_cap_for_kvm_ioctl() doesn't
  find the ioctl number in vm_ioc…
severity: none
vendor: Linux
product: Linux
affected:
  - >-
    Linux >= b12b3b04f6ba072ca5a618a75e546c996be94bd1 <
    cc53eb5c6515e3221314624a22c9da9c80a67f63
  - >-
    Linux >= b12b3b04f6ba072ca5a618a75e546c996be94bd1 <
    49d9d295d69d07e850cae35933ba8519e2915f26
  - Linux 7.0
published: '2026-10-18'
updated: '2026-10-18'
sourceUpdated: '2026-10-18T15:15:22.878Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-98470'
references:
  - url: 'https://git.kernel.org/stable/c/cc53eb5c6515e3221314624a22c9da9c80a67f63'
  - url: 'https://git.kernel.org/stable/c/49d9d295d69d07e850cae35933ba8519e2915f26'
tags:
  - cve.org
ingestedAt: '2026-10-18T15:45:12.297Z'
---

## Overview

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

KVM: arm64: Don't WARN on an unknown VM ioctl in protected mode

kvm_pkvm_ioctl_allowed() WARNs when kvm_get_cap_for_kvm_ioctl() doesn't
find the ioctl number in vm_ioctl_caps[], and kvm_arch_vm_ioctl() calls
it for every number the generic code doesn't handle, so
ioctl(vm_fd, 0xdeadbeef) from userspace taints a pKVM host and panics it
under panic_on_warn. The lookup is fed userspace input: return false,
and userspace gets the -EINVAL kvm_arch_vm_ioctl() returns for that
number on a host without pKVM.

## Affected

- `Linux >= b12b3b04f6ba072ca5a618a75e546c996be94bd1 < cc53eb5c6515e3221314624a22c9da9c80a67f63`
- `Linux >= b12b3b04f6ba072ca5a618a75e546c996be94bd1 < 49d9d295d69d07e850cae35933ba8519e2915f26`
- `Linux 7.0`

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.