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Fencer Vulns
medium 5.5

CVE-2026-23163 json

drm/amdgpu: fix NULL pointer dereference in amdgpu_gmc_filter_faults_remove

published 2026-02-14 8 mo ago modified 2026-11-05 3 d ago also EUVD-2026-5876

cvss
5.5
version 3.1, NVD
cisa kev
Not listed
not in CISA's catalog
epss
0.1%
EPSS 0.1% chance of exploitation in 30 days, percentile 2%
public exploits
0
none known

Summary

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

drm/amdgpu: fix NULL pointer dereference in amdgpu_gmc_filter_faults_remove

On APUs such as Raven and Renoir (GC 9.1.0, 9.2.2, 9.3.0), the ih1 and ih2 interrupt ring buffers are not initialized. This is by design, as these secondary IH rings are only available on discrete GPUs. See vega10_ih_sw_init() which explicitly skips ih1/ih2 initialization when AMD_IS_APU is set.

However, amdgpu_gmc_filter_faults_remove() unconditionally uses ih1 to get the timestamp of the last interrupt entry. When retry faults are enabled on APUs (noretry=0), this function is called from the SVM page fault recovery path, resulting in a NULL pointer dereference when amdgpu_ih_decode_iv_ts_helper() attempts to access ih->ring[].

The crash manifests as:

BUG: kernel NULL pointer dereference, address: 0000000000000004 RIP: 0010:amdgpu_ih_decode_iv_ts_helper+0x22/0x40 [amdgpu] Call Trace: amdgpu_gmc_filter_faults_remove+0x60/0x130 [amdgpu] svm_range_restore_pages+0xae5/0x11c0 [amdgpu] amdgpu_vm_handle_fault+0xc8/0x340 [amdgpu] gmc_v9_0_process_interrupt+0x191/0x220 [amdgpu] amdgpu_irq_dispatch+0xed/0x2c0 [amdgpu] amdgpu_ih_process+0x84/0x100 [amdgpu]

This issue was exposed by commit 1446226d32a4 ("drm/amdgpu: Remove GC HW IP 9.3.0 from noretry=1") which changed the default for Renoir APU from noretry=1 to noretry=0, enabling retry fault handling and thus exercising the buggy code path.

Fix this by adding a check for ih1.ring_size before attempting to use it. Also restore the soft_ih support from commit dd299441654f ("drm/amdgpu: Rework retry fault removal"). This is needed if the hardware doesn't support secondary HW IH rings.

v2: additional updates (Alex)

(cherry picked from commit 6ce8d536c80aa1f059e82184f0d1994436b1d526)

Patch / fix

  • Linux Linux 6.6.123, 6.12.69, 6.18.9, 6.19
  • linux Debian 13 6.12.69-1
  • linux Debian 14 6.18.9-1

debian advisories DEBIAN-CVE-2026-23163

  • linux Ubuntu 24.04 LTS 6.8.0-117.117
  • linux-aws Ubuntu 24.04 LTS 6.8.0-1055.58
  • linux-gcp Ubuntu 24.04 LTS 6.8.0-1058.61
  • linux-gke Ubuntu 24.04 LTS 6.8.0-1054.60
  • linux-ibm Ubuntu 24.04 LTS 6.8.0-1055.56
  • linux-azure Ubuntu 24.04 LTS 6.8.0-1056.62
  • linux-gkeop Ubuntu 24.04 LTS 6.8.0-1041.44
  • linux-raspi Ubuntu 24.04 LTS 6.8.0-1056.60

ubuntu advisories UBUNTU-CVE-2026-23163

Ubuntu security data © Canonical Ltd., from https://github.com/canonical/ubuntu-security-notices via OSV; changed: normalised to fixed package versions per release. CC BY-SA 4.0

  • kernel-64kb SLE Module for Basesystem 15 SP7 6.4.0-150700.53.34.1
  • kernel-syms SLE Module for Development Tools 15 SP7 6.4.0-150700.53.34.1
  • kernel-azure SLE Module for Public Cloud 15 SP7 6.4.0-150700.53.34.1
  • kernel-source SLE Module for Development Tools 15 SP7, SLE Module for Basesystem 15 SP7 6.4.0-150700.53.34.1
  • kernel-default SLE Workstation Extension 15 SP7, SLE Module for Legacy 15 SP7, SLE Module for Basesystem 15 SP7 +2 more 6.4.0-150700.53.34.1
  • kernel-zfcpdump SLE Module for Basesystem 15 SP7 6.4.0-150700.53.34.1
  • kernel-obs-build SLE Module for Development Tools 15 SP7 6.4.0-150700.53.34.1
  • kernel-default-base SLE Module for Basesystem 15 SP7 6.4.0-150700.53.34.1.150700.17.23.1

suse advisories SUSE-SU-2026:1081-1SUSE-SU-2026:20873-1SUSE-SU-2026:20838-1SUSE-SU-2026:20931-1SUSE-SU-2026:20845-1SUSE-SU-2026:20876-1

  • kernel-rt openSUSE Leap 16.0 6.12.0-160000.27.1
  • dtb-aarch64 openSUSE Leap 16.0 6.12.0-160000.27.1
  • kernel-64kb openSUSE Leap 16.0 6.12.0-160000.27.1
  • kernel-syms openSUSE Leap 16.0 6.12.0-160000.27.1
  • kernel-azure openSUSE Leap 16.0 6.12.0-160000.27.1
  • kernel-obs-qa openSUSE Leap 16.0 6.12.0-160000.27.1
  • kernel-source openSUSE Leap 16.0 6.12.0-160000.27.1
  • kernel-default openSUSE Leap 16.0 6.12.0-160000.27.1

opensuse advisories openSUSE-SU-2026:20416-1

  • kernel Azure Linux 3.0 6.6.126.1-1

azure linux advisories AZL-77760

Azure Linux vulnerability data, Copyright (c) Microsoft Corporation, from https://github.com/microsoft/AzureLinuxVulnerabilityData via OSV, under the MIT licence; changed: normalised to fixed package versions per release. MIT

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2026-23163 updated cvss 5.5

kernel: drm/amdgpu: fix NULL pointer dereference in amdgpu_gmc_filter_faults_remove

  • Red Hat Enterprise Linux 6 perf, kernel, python-perf, kernel-kdump, kernel-firmware, kernel-bootwrapper, +1 more
    affected: no fix planned “Out of support scope”
  • Red Hat Enterprise Linux 9 rv, perf, rtla, kernel, bpftool, libperf, +82 more Red Hat Enterprise Linux 10 kernel
    affected: no fix available “Fix deferred”
  • Red Hat Enterprise Linux 7 perf, kernel, bpftool, kernel-rt, python-perf, kernel-kdump, +8 more Red Hat Enterprise Linux 8 perf, kernel, bpftool, kernel-rt, kernel-core, kernel-tools, +29 more Red Hat Enterprise Linux 9 kernel-rt, kernel-rt-selftests-internal
    not affected: vulnerable code not present

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

CISA SSVC

Exploitation
none
Automatable
no
Technical impact
partial
Assessed
3 d ago

Exploit prediction

0.13% chance of exploitation in the next 30 days, higher than 2% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by version score vector
NVD 3.1 5.5 CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Affected products

  • Linux Linux

Classification

Weakness
Technology feeds

References

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.