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

drm/amdkfd: Avoid integer underflow in EOP ring size calculation.

The low 6 bits of cp_hqd_eop_control store the base-2 logarithm
of the EOP ring size. This was calculated as

order_base_2(q->eop_ring_buffer_size / 4) - 1

But order_base_2 can in theory return 0, so this could underflow
(although in practice the ring buffer size cannot be less than 4096).

Change this to

order_base_2(q->eop_ring_buffer_size / 8)

using properties of logarithms.

Also add to the above comment to make the mathematics more clear.

(cherry picked from commit f0f43fcf8b2b3a924cad9444340921c96ed5f634)
Published: 2026-10-06
Score: n/a
EPSS: n/a
KEV: No
Impact: n/a
Action: n/a
AI Analysis

No analysis available yet.

Remediation

No remediation available yet.

Tracking

Sign in to view the affected projects.

Advisories

No advisories yet.

History

Tue, 06 Oct 2026 09:00:00 +0000

Type Values Removed Values Added
Description In the Linux kernel, the following vulnerability has been resolved: drm/amdkfd: Avoid integer underflow in EOP ring size calculation. The low 6 bits of cp_hqd_eop_control store the base-2 logarithm of the EOP ring size. This was calculated as order_base_2(q->eop_ring_buffer_size / 4) - 1 But order_base_2 can in theory return 0, so this could underflow (although in practice the ring buffer size cannot be less than 4096). Change this to order_base_2(q->eop_ring_buffer_size / 8) using properties of logarithms. Also add to the above comment to make the mathematics more clear. (cherry picked from commit f0f43fcf8b2b3a924cad9444340921c96ed5f634)
Title drm/amdkfd: Avoid integer underflow in EOP ring size calculation.
First Time appeared Linux
Linux linux Kernel
CPEs cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
Vendors & Products Linux
Linux linux Kernel
References

Subscriptions

Linux Linux Kernel
cve-icon MITRE

Status: PUBLISHED

Assigner: Linux

Published:

Updated: 2026-10-06T08:44:20.807Z

Reserved: 2026-09-25T10:25:14.322Z

Link: CVE-2026-98177

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Received

Published: 2026-10-06T09:17:59.787

Modified: 2026-10-06T09:17:59.787

Link: CVE-2026-98177

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

No data.

Weaknesses

No weakness.