CVE-2026-89819

Full vulnerability record from the local CVENow database.

Description

In the Linux kernel, the following vulnerability has been resolved: drm/amd/display: validate plane degamma LUT size for private color prop Unlike the CRTC degamma path, which is guarded by amdgpu_dm_verify_lut_sizes(), the per-plane degamma LUT size was never validated before use. __set_dm_plane_degamma() passed the user-supplied size straight into __is_lut_linear() and, for a non-linear LUT, into __set_input_tf() -> __drm_lut_to_dc_gamma(), the latter always iterating MAX_COLOR_LUT_ENTRIES entries regardless of the actual LUT size. A malformed AMD_PLANE_DEGAMMA_LUT blob (e.g. a single entry) could thus trigger a divide-by-zero in __is_lut_linear() or an out-of-bounds read in __drm_lut_to_dc_gamma(). Reject any plane degamma LUT whose size does not match MAX_COLOR_LUT_ENTRIES, mirroring the invariant the code already asserts a few lines below (and which the CRTC path enforces). The AMD_PLANE_DEGAMMA_LUT property is only exposed on builds with AMD_PRIVATE_COLOR defined.

Severity

HIGH

CVSS score

7.8 (v3.1)

Vulnerability status

Received

Source identifier

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

Published

2026-09-16 11:16:47.253000

Last modified

2026-10-19 09:18:25.810000

View original CVE JSON

{
  "id": "CVE-2026-89819",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "published": "2026-09-16T11:16:47.253",
  "lastModified": "2026-10-19T09:18:25.810",
  "vulnStatus": "Received",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\ndrm/amd/display: validate plane degamma LUT size for private color prop\n\nUnlike the CRTC degamma path, which is guarded by\namdgpu_dm_verify_lut_sizes(), the per-plane degamma LUT size was never\nvalidated before use. __set_dm_plane_degamma() passed the user-supplied\nsize straight into __is_lut_linear() and, for a non-linear LUT, into\n__set_input_tf() -> __drm_lut_to_dc_gamma(), the latter always iterating\nMAX_COLOR_LUT_ENTRIES entries regardless of the actual LUT size.\n\nA malformed AMD_PLANE_DEGAMMA_LUT blob (e.g. a single entry) could thus\ntrigger a divide-by-zero in __is_lut_linear() or an out-of-bounds read in\n__drm_lut_to_dc_gamma(). Reject any plane degamma LUT whose size does not\nmatch MAX_COLOR_LUT_ENTRIES, mirroring the invariant the code already\nasserts a few lines below (and which the CRTC path enforces).\n\nThe AMD_PLANE_DEGAMMA_LUT property is only exposed on builds with\nAMD_PRIVATE_COLOR defined."
    }
  ],
  "affected": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "affectedData": [
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "unaffected",
          "programFiles": [
            "drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_color.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "980f8710075acaeb226a94cde6dda8ffad30123c",
              "lessThan": "f6f04d8ae5725bcc893bdc62e3467efd97255c5b",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "980f8710075acaeb226a94cde6dda8ffad30123c",
              "lessThan": "0b2615b8b54f58bbdf986dffb38cbc35214a5cc5",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "980f8710075acaeb226a94cde6dda8ffad30123c",
              "lessThan": "b10cc09b329245c6d95f8fa3e7f068575e3e0e9f",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "980f8710075acaeb226a94cde6dda8ffad30123c",
              "lessThan": "e4c3ab59021e7c146a84b6671f0d530972bd58b4",
              "versionType": "git",
              "status": "affected"
            }
          ]
        },
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "affected",
          "programFiles": [
            "drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_color.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "6.8",
              "status": "affected"
            },
            {
              "version": "0",
              "lessThan": "6.8",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.12.110",
              "lessThanOrEqual": "6.12.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.18.51",
              "lessThanOrEqual": "6.18.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.2.5",
              "lessThanOrEqual": "7.2.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.3",
              "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
      }
    ]
  },
  "references": [
    {
      "url": "https://git.kernel.org/stable/c/0b2615b8b54f58bbdf986dffb38cbc35214a5cc5",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/b10cc09b329245c6d95f8fa3e7f068575e3e0e9f",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/e4c3ab59021e7c146a84b6671f0d530972bd58b4",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/f6f04d8ae5725bcc893bdc62e3467efd97255c5b",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ]
}