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GHSA-V84F-F8J3-97Q7

Vulnerability from github – Published: 2026-08-10 15:33 – Updated: 2026-08-14 00:31

Details

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

7.8 (High)


                  
                    CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

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{
  "affected": [],
  "aliases": [
    "CVE-2026-68274"
  ],
  "database_specific": {
    "cwe_ids": [],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-08-10T13:20:16Z",
    "severity": "HIGH"
  },
  "details": "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-\u003efuse_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)",
  "id": "GHSA-v84f-f8j3-97q7",
  "modified": "2026-08-14T00:31:54Z",
  "published": "2026-08-10T15:33:44Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-68274"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/632ecc90e1ca5d3b6822bb4d08f84a175b6c42c0"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/a9a020f3c11eba6573b699f9cf9245a51b025ade"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/b485bfb45555163bfa5f565d6a3415fcb3035b02"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ]
}

CVE-2026-68274 (GCVE-0-2026-68274)

Vulnerability from cvelistv5 – Published: 2026-08-10 12:01 – Updated: 2026-08-17 05:02

Title

drm/xe/guc: Fix buffer overflow in steered register list allocation

Summary

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

7.8 (High)


                        
                          CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Assigner

Linux mitre root

References

3 references

URL	Tags
https://git.kernel.org/stable/c/b485bfb45555163bf…
https://git.kernel.org/stable/c/a9a020f3c11eba657…
https://git.kernel.org/stable/c/632ecc90e1ca5d3b6…

Impacted products

2 products

Vendor	Product	Version
Linux	Linux	Affected: b170d696c1e2226713471d810c63b1162335079f , < b485bfb45555163bfa5f565d6a3415fcb3035b02 (git) Affected: b170d696c1e2226713471d810c63b1162335079f , < a9a020f3c11eba6573b699f9cf9245a51b025ade (git) Affected: b170d696c1e2226713471d810c63b1162335079f , < 632ecc90e1ca5d3b6822bb4d08f84a175b6c42c0 (git)
Linux	Linux	Affected: 6.13 Unaffected: 0 , < 6.13 (semver) Unaffected: 6.18.44 , ≤ 6.18.* (semver) Unaffected: 7.1.6 , ≤ 7.1.* (semver) Unaffected: 7.2 , ≤ * (original_commit_for_fix)

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{
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    "cna": {
      "affected": [
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          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "drivers/gpu/drm/xe/xe_guc_capture.c"
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              "lessThan": "a9a020f3c11eba6573b699f9cf9245a51b025ade",
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            },
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              "versionType": "git"
            }
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          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "6.13"
            },
            {
              "lessThan": "6.13",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
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              "lessThanOrEqual": "6.18.*",
              "status": "unaffected",
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              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "7.1.*",
              "status": "unaffected",
              "version": "7.1.6",
              "versionType": "semver"
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              "status": "unaffected",
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              "versionType": "original_commit_for_fix"
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          "nodes": [
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                {
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              ],
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              "operator": "OR"
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      "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-\u003efuse_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)"
        }
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            "version": "3.1"
          },
          "scenarios": [
            {
              "lang": "en",
              "value": "AV:L - The flaw is in the drm/xe GPU driver\u0027s GuC ADS/capture-list setup, reached only through local kernel device probe/GuC upload on the machine\u0027s own hardware; there is no network or remote-peer input anywhere on the path.\nAC:L - On any affected platform (one whose compute DSS mask contains bits outside the geometry DSS mask) the undersized allocation and the for_each_dss_steering() fill loop mismatch is fully deterministic, so the out-of-bounds write occurs reliably on every driver load without needing a race or a lucky memory layout.\nPR:L - The overflow happens in the xe driver\u0027s GuC initialization path, so an attacker needs only ordinary local access to a system with the affected Intel GPU present; no capability check or elevated privilege gates the corrupted code path itself.\nUI:N - No victim action is needed; the buffer overflow occurs automatically during xe_guc_ads_populate() at device probe, with no file to open, filesystem to mount, or user gesture involved.\nS:U - The out-of-bounds write corrupts kernel slab objects belonging to the same kernel security authority; there is no crossing of a VM, IOMMU, or sandbox boundary.\nC:H - The overflow overwrites adjacent slab objects including drmres list_head pointers, and such heap metadata corruption can be leveraged to make subsequent list operations dereference attacker-influenceable heap contents, so an information-disclosure primitive cannot be ruled out.\nI:H - This is a heap out-of-bounds write past the end of the drmm_kzalloc\u0027d extarray, overwriting neighboring allocations\u0027 contents and list linkage, which is exactly the class of corruption that yields arbitrary-write and control-flow-hijack primitives.\nA:H - The corruption is confirmed to produce list_del corruption and SLUB redzone overwrites, causing kernel oops/panic during drm_managed_release on device unbind and unpredictable slab corruption beforehand."
            }
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        }
      ],
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        "dateUpdated": "2026-08-17T05:02:07.998Z",
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          "url": "https://git.kernel.org/stable/c/b485bfb45555163bfa5f565d6a3415fcb3035b02"
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          "url": "https://git.kernel.org/stable/c/a9a020f3c11eba6573b699f9cf9245a51b025ade"
        },
        {
          "url": "https://git.kernel.org/stable/c/632ecc90e1ca5d3b6822bb4d08f84a175b6c42c0"
        }
      ],
      "title": "drm/xe/guc: Fix buffer overflow in steered register list allocation",
      "x_generator": {
        "engine": "bippy-1.2.0"
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  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2026-68274",
    "datePublished": "2026-08-10T12:01:49.762Z",
    "dateReserved": "2026-07-30T09:28:09.379Z",
    "dateUpdated": "2026-08-17T05:02:07.998Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Detection rules are retrieved from Rulezet.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
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