CVE-2026-98176

Published: October 9, 2026Last modified: October 9, 2026

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)

Status

References

• https://git.kernel.org/stable/c/82e1b8299c6da02ce02185c208d2fdf7572b5ea1
• https://git.kernel.org/stable/c/c883d0a132d430ef7ebb23fd94323be94d0fbdb8