{"id":"CVE-2026-68274","title":"drm/xe/guc: Fix buffer overflow in steered register list allocation","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\ndrm/xe/guc: Fix buffer overflow in steered register list allocation\n\nThe size calculation for the steered register extarray uses only the\ngeometry DSS mask (g_dss_mask)…","severity":"high","cvss":7.8,"cvssVector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","cvssSource":"cna","vendor":"Linux","product":"Linux","affected":["Linux >= b170d696c1e2226713471d810c63b1162335079f < b485bfb45555163bfa5f565d6a3415fcb3035b02","Linux >= b170d696c1e2226713471d810c63b1162335079f < a9a020f3c11eba6573b699f9cf9245a51b025ade","Linux >= b170d696c1e2226713471d810c63b1162335079f < 632ecc90e1ca5d3b6822bb4d08f84a175b6c42c0","Linux 6.13"],"ssvc":{"exploitation":"none","automatable":"no","technicalImpact":"total","timestamp":"2026-10-16T15:46:31.440786Z"},"published":"2026-08-10","updated":"2026-10-16","sourceUpdated":"2026-10-16T15:53:05.971Z","source":"CVEORG","sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-68274","references":[{"url":"https://git.kernel.org/stable/c/b485bfb45555163bfa5f565d6a3415fcb3035b02"},{"url":"https://git.kernel.org/stable/c/a9a020f3c11eba6573b699f9cf9245a51b025ade"},{"url":"https://git.kernel.org/stable/c/632ecc90e1ca5d3b6822bb4d08f84a175b6c42c0"}],"tags":["cve.org"],"epss":0.00151,"epssPercentile":0.03835,"ingestedAt":"2026-10-16T17:24:46.853Z","slug":"CVE-2026-68274","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\ndrm/xe/guc: Fix buffer overflow in steered register list allocation\n\nThe size calculation for the steered register extarray uses only the\ngeometry DSS mask (g_dss_mask) to determine the number of entries to\nallocate:\n\n  total = bitmap_weight(gt->fuse_topo.g_dss_mask, ...) * steer_reg_num;\n\nHowever, the filling loop uses for_each_dss_steering(), which iterates\nover for_each_dss(), defined as the union of g_dss_mask and c_dss_mask\n(geometry + compute DSS). On platforms with compute-only DSS bits, the\nloop writes past the allocated buffer, corrupting adjacent slab objects.\n\nThis manifests as list_del corruption and SLUB redzone overwrites during\ndrm_managed_release on device unbind, since the overflow corrupts the\ndrmres list_head of neighboring allocations.\n\nFix by computing the allocation size using the union of both DSS masks,\nmatching the iteration pattern of for_each_dss_steering().\n\n--\nv2:\n- use bitmap_weighted_or() (Zhanjun)\n\n(cherry picked from commit 0a78a44f4901aa6c9263e66be7fce02282f1109f)\n\n## Affected\n\n- `Linux >= b170d696c1e2226713471d810c63b1162335079f < b485bfb45555163bfa5f565d6a3415fcb3035b02`\n- `Linux >= b170d696c1e2226713471d810c63b1162335079f < a9a020f3c11eba6573b699f9cf9245a51b025ade`\n- `Linux >= b170d696c1e2226713471d810c63b1162335079f < 632ecc90e1ca5d3b6822bb4d08f84a175b6c42c0`\n- `Linux 6.13`\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"twilight","depthScore":43,"depthScoreParts":{"impact":42.9,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}