---
id: CVE-2026-81016
title: |-
  In the Linux kernel, the following vulnerability has been resolved:

  platform/x86/amd/pmc: Propagate SMU errors and validate S2D address

  amd_stb_s2d_init() discards the return value of several S2D SMU commands.
  When the SMU refuses a co…
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  platform/x86/amd/pmc: Propagate SMU errors and validate S2D address

  amd_stb_s2d_init() discards the return value of several S2D SMU commands.
  When the SMU refuses a co…
severity: high
cvss: 7.7
cvssVector: 'CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H'
cwe:
  - CWE-908
vendor: Linux
product: Linux
affected:
  - >-
    Linux >= 3d7d407dfb05b257e15cb0c6b056428a4a8c2e5d <
    638e1ca5d4e2b4fdbb209db64926d013b34f3b79
  - >-
    Linux >= 3d7d407dfb05b257e15cb0c6b056428a4a8c2e5d <
    8178f59d76570b152d836bde07f5997f15861f04
  - >-
    Linux >= 3d7d407dfb05b257e15cb0c6b056428a4a8c2e5d <
    775d4cde1f9737796ce7d8393521e9e8c5b49891
  - >-
    Linux >= 3d7d407dfb05b257e15cb0c6b056428a4a8c2e5d <
    0225c1d637687b03726f00ac65b6def843d2c464
  - Linux 5.18
published: '2026-09-11'
updated: '2026-10-03'
sourceUpdated: '2026-10-03T11:17:41.710'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-81016'
references:
  - url: 'https://git.kernel.org/stable/c/0225c1d637687b03726f00ac65b6def843d2c464'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/638e1ca5d4e2b4fdbb209db64926d013b34f3b79'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/775d4cde1f9737796ce7d8393521e9e8c5b49891'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/8178f59d76570b152d836bde07f5997f15861f04'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: >-
      https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-81016.json
  - url: 'https://access.redhat.com/security/cve/CVE-2026-81016'
  - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2532049'
  - url: 'https://www.cve.org/CVERecord?id=CVE-2026-81016'
  - url: 'https://nvd.nist.gov/vuln/detail/CVE-2026-81016'
  - url: >-
      https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-81016.mbox
  - url: 'https://git.kernel.org/stable/c/85ef9d4c384c1d143c51580933674d94dba3b8d9'
tags:
  - nvd
  - cve.org
  - csaf
  - vex
  - red-hat
  - score-dispute
epss: 0.00186
epssPercentile: 0.0808
scores:
  nvd: 7.7
  vendor: 5.5
  cna: 7.7
ingestedAt: '2026-09-14T15:23:07.475Z'
---

## Overview

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

platform/x86/amd/pmc: Propagate SMU errors and validate S2D address

amd_stb_s2d_init() discards the return value of several S2D SMU commands.
When the SMU refuses a command (e.g. "SMU cmd failed. err: 0xff") the
failure is only noticed indirectly - if at all - and reported as -EIO,
masking the real error.

More seriously, the S2D_PHYS_ADDR_LOW/HIGH return values are ignored, so
on failure phys_addr_low/hi are left uninitialised and the assembled
address is passed straight to devm_ioremap().  When the SMU leaves them at
zero this maps physical address 0 and trips the ioremap-on-RAM warning:

  amd_pmc AMDI000B:00: SMU cmd failed. err: 0xff
  ioremap on RAM at 0x0000000000000000 - 0x0000000000ffffff
  WARNING: CPU: 13 PID: 4592 at arch/x86/mm/ioremap.c:...

Check the return value of each SMU command and propagate it, and reject a
zero physical address before calling devm_ioremap().

## Remediation

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

## Vendor advisories

- **Red Hat VEX** · Moderate · affected: Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 9, Red Hat OpenShift Container Platform 4 · no fix planned: Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 9, Red Hat OpenShift Container Platform 4 · updated 2026-10-17 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-81016.json)