CVE-2026-53325 – agp/amd64: Fix broken error propagation in agp_amd64_probe()

CVE ID :CVE-2026-53325

Published : June 29, 2026, 4:53 a.m. | 52 minutes ago

Description :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 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.

Severity: 0.0 | NA

Visit the link for more details, such as CVSS details, affected products, timeline, and more…