CVE-2026-68274

Full vulnerability record from the local CVENow database.

Description

In the Linux kernel, the following vulnerability has been resolved: drm/xe/guc: Fix buffer overflow in steered register list allocation The size calculation for the steered register extarray uses only the geometry DSS mask (g_dss_mask) to determine the number of entries to allocate: total = bitmap_weight(gt->fuse_topo.g_dss_mask, ...) * steer_reg_num; However, the filling loop uses for_each_dss_steering(), which iterates over for_each_dss(), defined as the union of g_dss_mask and c_dss_mask (geometry + compute DSS). On platforms with compute-only DSS bits, the loop writes past the allocated buffer, corrupting adjacent slab objects. This manifests as list_del corruption and SLUB redzone overwrites during drm_managed_release on device unbind, since the overflow corrupts the drmres list_head of neighboring allocations. Fix by computing the allocation size using the union of both DSS masks, matching the iteration pattern of for_each_dss_steering(). -- v2: - use bitmap_weighted_or() (Zhanjun) (cherry picked from commit 0a78a44f4901aa6c9263e66be7fce02282f1109f)

Severity

HIGH

CVSS score

7.8 (v3.1)

Vulnerability status

Received

Source identifier

416baaa9-dc9f-4396-8d5f-8c081fb06d67

Published

2026-08-10 13:20:16.467000

Last modified

2026-10-19 21:18:00.577000

View original CVE JSON

{
  "id": "CVE-2026-68274",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "published": "2026-08-10T13:20:16.467",
  "lastModified": "2026-10-19T21:18:00.577",
  "vulnStatus": "Received",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "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) 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)"
    }
  ],
  "affected": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "affectedData": [
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "unaffected",
          "programFiles": [
            "drivers/gpu/drm/xe/xe_guc_capture.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "b170d696c1e2226713471d810c63b1162335079f",
              "lessThan": "b485bfb45555163bfa5f565d6a3415fcb3035b02",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "b170d696c1e2226713471d810c63b1162335079f",
              "lessThan": "a9a020f3c11eba6573b699f9cf9245a51b025ade",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "b170d696c1e2226713471d810c63b1162335079f",
              "lessThan": "632ecc90e1ca5d3b6822bb4d08f84a175b6c42c0",
              "versionType": "git",
              "status": "affected"
            }
          ]
        },
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "affected",
          "programFiles": [
            "drivers/gpu/drm/xe/xe_guc_capture.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "6.13",
              "status": "affected"
            },
            {
              "version": "0",
              "lessThan": "6.13",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.18.44",
              "lessThanOrEqual": "6.18.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.1.6",
              "lessThanOrEqual": "7.1.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.2",
              "lessThanOrEqual": "*",
              "versionType": "original_commit_for_fix",
              "status": "unaffected"
            }
          ]
        }
      ]
    }
  ],
  "metrics": {
    "cvssMetricV31": [
      {
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "type": "Secondary",
        "cvssData": {
          "version": "3.1",
          "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
          "baseScore": 7.8,
          "baseSeverity": "HIGH",
          "attackVector": "LOCAL",
          "attackComplexity": "LOW",
          "privilegesRequired": "LOW",
          "userInteraction": "NONE",
          "scope": "UNCHANGED",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "HIGH",
          "availabilityImpact": "HIGH"
        },
        "exploitabilityScore": 1.8,
        "impactScore": 5.9
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "timestamp": "2026-10-16T15:46:31.440786Z",
          "id": "CVE-2026-68274",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "total"
            }
          ],
          "role": "CISA Coordinator",
          "version": "2.0.3"
        }
      }
    ]
  },
  "weaknesses": [
    {
      "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
      "type": "Secondary",
      "description": [
        {
          "lang": "en",
          "value": "CWE-787"
        }
      ]
    }
  ],
  "references": [
    {
      "url": "https://git.kernel.org/stable/c/632ecc90e1ca5d3b6822bb4d08f84a175b6c42c0",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/a9a020f3c11eba6573b699f9cf9245a51b025ade",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/b485bfb45555163bfa5f565d6a3415fcb3035b02",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ]
}