CVE-2024-26721: In the Linux kernel, the following vulnerability has been resolved: drm/i915/dsc: Fix the macro that calculates DSCC_/DSCA_ PPS reg address Commit b...

Description

In the Linux kernel, the following vulnerability has been resolved: drm/i915/dsc: Fix the macro that calculates DSCC_/DSCA_ PPS reg address Commit bd077259d0a9 ("drm/i915/vdsc: Add function to read any PPS register") defines a new macro to calculate the DSC PPS register addresses with PPS number as an input. This macro correctly calculates the addresses till PPS 11 since the addresses increment by 4. So in that case the following macro works correctly to give correct register address: _MMIO(_DSCA_PPS_0 + (pps) * 4) However after PPS 11, the register address for PPS 12 increments by 12 because of RC Buffer memory allocation in between. Because of this discontinuity in the address space, the macro calculates wrong addresses for PPS 12 - 16 resulting into incorrect DSC PPS parameter value read/writes causing DSC corruption. This fixes it by correcting this macro to add the offset of 12 for PPS >=12. v3: Add correct paranthesis for pps argument (Jani Nikula) (cherry picked from commit 6074be620c31dc2ae11af96a1a5ea95580976fb5)

Metrics

CVSS 3.1

5.5/10

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

EPSS Probability

0.20%

9.5th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-131

Affected Software

Vendor	Product	Versions	Update
Linux	Linux Kernel	>= 6.7, < 6.7.6	—
Linux	Linux Kernel	6.8	Rc1

References

Timeline

Published: Apr 3, 2024
Last Modified: Jun 17, 2026
Status: Analyzed

Frequently Asked Questions

What is CVE-2024-26721?

In the Linux kernel, the following vulnerability has been resolved: drm/i915/dsc: Fix the macro that calculates DSCC_/DSCA_ PPS reg address Commit bd077259d0a9 ("drm/i915/vdsc: Add function to read any PPS register") defines a new macro to calculate the DSC PPS register addresses with PPS number as an input. This macro correctly calculates the addresses till PPS 11 since the addresses increment by 4. So in that case the following macro works correctly to give correct register address: _MMIO(_DSCA_PPS_0 + (pps) * 4) However after PPS 11, the register address for PPS 12 increments by 12 because of RC Buffer memory allocation in between. Because of this discontinuity in the address space, the macro calculates wrong addresses for PPS 12 - 16 resulting into incorrect DSC PPS parameter value read/writes causing DSC corruption. This fixes it by correcting this macro to add the offset of 12 for PPS >=12. v3: Add correct paranthesis for pps argument (Jani Nikula) (cherry picked from commit 6074be620c31dc2ae11af96a1a5ea95580976fb5)

How severe is CVE-2024-26721?

CVE-2024-26721 has a CVSS score of 5.5/10 (MEDIUM severity). The EPSS model estimates a 0.20% probability of exploitation in the next 30 days.

How do I fix CVE-2024-26721?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.