---
id: CVE-2026-53325
title: |-
  In the Linux kernel, the following vulnerability has been resolved:

  agp/amd64: Fix broken error propagation in agp_amd64_probe()

  A NULL pointer dereference was observed in the AMD64 AGP driver when
  running in a virtualized environment …
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  agp/amd64: Fix broken error propagation in agp_amd64_probe()

  A NULL pointer dereference was observed in the AMD64 AGP driver when
  running in a virtualized environment …
severity: none
published: '2026-06-29'
updated: '2026-06-29'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-53325'
references:
  - url: 'https://git.kernel.org/stable/c/0aa9b27c454c53074cde592eaceb442d30341585'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/53483a9f4ee9eeb18aa866ec16cce79e136987e1'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/b08472db93b1ccff84a7adec5779d47f0e9d3a30'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/cefe535a60a2e00e09f4b2689b0c8ffc6912459a'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
tags:
  - nvd
ingestedAt: '2026-06-29T13:42:12.354Z'
epss: 0.00126
epssPercentile: 0.01945
---

## Overview

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

agp/amd64: Fix broken error propagation in agp_amd64_probe()

A NULL pointer dereference was observed in the AMD64 AGP driver when
running in a virtualized environment (e.g. qemu/kvm) without a physical
AMD northbridge. The crash occurs in amd64_fetch_size() when attempting
to dereference the pointer returned by node_to_amd_nb(0).

The root cause of this crash is broken error propagation in
agp_amd64_probe(): When no AMD northbridges are found, cache_nbs()
correctly returns -ENODEV. However, the probe function erroneously
checks the return value against exactly -1, rather than < 0.

As a result, the hardware absence error is masked, allowing the driver
to improperly proceed with initialization. It eventually calls
agp_add_bridge(), which invokes amd64_fetch_size(). Since the hardware
does not exist, node_to_amd_nb(0) returns NULL, leading to a General
Protection Fault (GPF) when accessing its ->misc member.

Fix the issue by correcting the error check in agp_amd64_probe() to
abort properly when cache_nbs() returns any negative error code. This
prevents the driver from erroneously proceeding without hardware, thereby
avoiding the subsequent NULL pointer dereference at its source.

## Remediation

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