---
id: CVE-2026-92521
title: |-
  In the Linux kernel, the following vulnerability has been resolved:

  ACPI: PCI: Clear driver_data on all paths that free the acpi_pci_root

  acpi_pci_root_add() assigns the freshly allocated root to
  device->driver_data before dmar_device_…
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  ACPI: PCI: Clear driver_data on all paths that free the acpi_pci_root

  acpi_pci_root_add() assigns the freshly allocated root to
  device->driver_data before dmar_device_…
severity: none
vendor: Linux
product: Linux
affected:
  - >-
    Linux >= db89b4f0dbab837d0f3de2c3e9427a8d5393afa3 <
    321bb0eb1486a0d575f02e24e3f4170e408c2f51
  - >-
    Linux >= db89b4f0dbab837d0f3de2c3e9427a8d5393afa3 <
    3c1e8a14f9d06c1ed6f3e4bd2d283a62079109e2
  - >-
    Linux >= db89b4f0dbab837d0f3de2c3e9427a8d5393afa3 <
    a285fa3780c768dcc51c76768707d099a2cc611d
  - >-
    Linux >= db89b4f0dbab837d0f3de2c3e9427a8d5393afa3 <
    6aaf6dbf54fdfae096f3f90a79e9614e46579280
  - >-
    Linux >= db89b4f0dbab837d0f3de2c3e9427a8d5393afa3 <
    70cf773cca30a10b4964c24520a71279c974b899
  - >-
    Linux >= db89b4f0dbab837d0f3de2c3e9427a8d5393afa3 <
    3eee4c21931dc048ce63b86809f04e4e6f0dcad5
  - >-
    Linux >= db89b4f0dbab837d0f3de2c3e9427a8d5393afa3 <
    6e11ac626f9f9fc3a2ed27dfa44ccbe5fb762217
  - >-
    Linux >= db89b4f0dbab837d0f3de2c3e9427a8d5393afa3 <
    8a742141f7ab84975aa758b775567ef4740ef0cf
  - Linux 2.6.28
published: '2026-09-17'
updated: '2026-09-17'
sourceUpdated: '2026-09-17T17:17:55.013'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-92521'
references:
  - url: 'https://git.kernel.org/stable/c/321bb0eb1486a0d575f02e24e3f4170e408c2f51'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/3c1e8a14f9d06c1ed6f3e4bd2d283a62079109e2'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/3eee4c21931dc048ce63b86809f04e4e6f0dcad5'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/6aaf6dbf54fdfae096f3f90a79e9614e46579280'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/6e11ac626f9f9fc3a2ed27dfa44ccbe5fb762217'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/70cf773cca30a10b4964c24520a71279c974b899'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/8a742141f7ab84975aa758b775567ef4740ef0cf'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/a285fa3780c768dcc51c76768707d099a2cc611d'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
tags:
  - nvd
  - cve.org
ingestedAt: '2026-09-17T16:21:47.776Z'
epss: 0.0022
epssPercentile: 0.11151
---

## Overview

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

ACPI: PCI: Clear driver_data on all paths that free the acpi_pci_root

acpi_pci_root_add() assigns the freshly allocated root to
device->driver_data before dmar_device_add() and pci_acpi_scan_root().
Both failure paths reach the end: label where root is kfree()'d, but
only the pci_acpi_scan_root() path clears driver_data first.

When dmar_device_add() fails during a hot-add, root is freed while
device->driver_data still points at it.  The ACPI core does not clear
driver_data on attach failure, so a later acpi_pci_find_root() call may
dereference this dangling pointer.

acpi_pci_root_remove() has the same problem: it frees root without
clearing device->driver_data, leaving a dangling pointer behind after
the root bridge is removed.

Move the NULL assignment to the shared end: label so every error path in
acpi_pci_root_add() clears driver_data before freeing root, and clear it
in acpi_pci_root_remove() as well, so the object is never left reachable
through driver_data after being freed.

## Remediation

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