{"id":"CVE-2026-98177","summary":"drm/amdkfd: Avoid integer underflow in EOP ring size calculation.","details":"In the Linux kernel, the following vulnerability has been resolved:\n\ndrm/amdkfd: Avoid integer underflow in EOP ring size calculation.\n\nThe low 6 bits of cp_hqd_eop_control store the base-2 logarithm\nof the EOP ring size. This was calculated as\n\norder_base_2(q-\u003eeop_ring_buffer_size / 4) - 1\n\nBut order_base_2 can in theory return 0, so this could underflow\n(although in practice the ring buffer size cannot be less than 4096).\n\nChange this to\n\norder_base_2(q-\u003eeop_ring_buffer_size / 8)\n\nusing properties of logarithms.\n\nAlso add to the above comment to make the mathematics more clear.\n\n(cherry picked from commit f0f43fcf8b2b3a924cad9444340921c96ed5f634)","modified":"2026-10-08T02:52:50.498268494Z","published":"2026-10-06T08:44:20.807Z","database_specific":{"cna_assigner":"Linux","osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/98xxx/CVE-2026-98177.json"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/287a34c4d712e0bdb67751e21316d9c8d75a528a"},{"type":"WEB","url":"https://git.kernel.org/stable/c/8ee521b8b189799e361d4233c5180ba56656d4d4"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/98xxx/CVE-2026-98177.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-98177"},{"type":"PACKAGE","url":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"d696d536f0a97ac779d6176107ac4e96d0a2f8b9"},{"fixed":"287a34c4d712e0bdb67751e21316d9c8d75a528a"},{"fixed":"8ee521b8b189799e361d4233c5180ba56656d4d4"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-98177.json"}},{"package":{"name":"Kernel","ecosystem":"Linux"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"4.3.0"},{"fixed":"7.2.8"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-98177.json"}}],"schema_version":"1.9.0"}