CVE-2026-98176 drm/amdkfd: Avoid integer underflow with ffs in EOP ring size calc
A local attacker can trigger an integer underflow in the AMD KFD driver, potentially causing a denial of service.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-98176?
CVE-2026-98176 is a vulnerability in Linux, published on 6 Oct 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
In the Linux kernel, the following vulnerability has been resolved:
drm/amdkfd: Avoid integer underflow with ffs in EOP ring size calc
The low 6 bits of cp_hqd_eop_control store the base-2 logarithm of the EOP ring size. This was calculated as
ffs(q->eop_ring_buffer_size / sizeof(unsigned int)) - 1 - 1
But ffs can in theory return 1 or 0, so this could underflow (although in practice the ring buffer size cannot be less than 4096).
Change this to
ffs(q->eop_ring_buffer_size / sizeof(unsigned int) / 4)
using properties of logarithms.
(cherry picked from commit 4f18c56630383c14bfc6b2d65f88f2f895d2121a)
Which versions are affected by CVE-2026-98176?
How do I fix CVE-2026-98176?
Apply the vendor's patch.
Is CVE-2026-98176 being exploited?
There is no known exploitation of CVE-2026-98176 in the wild and no public exploit code.
Sources
Also known as AZL-106263, BELL-CVE-2026-98176, DEBIAN-CVE-2026-98176, GHSA-mv47-6r4w-p28q, UBUNTU-CVE-2026-98176.