{
  "schemaVersion": 1,
  "attribution": [
    {
      "source": "CISA Known Exploited Vulnerabilities",
      "url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog",
      "licence": "US government work"
    },
    {
      "source": "GitHub Advisory Database",
      "url": "https://github.com/advisories",
      "licence": "CC BY 4.0"
    },
    {
      "source": "Have I Been Pwned",
      "url": "https://haveibeenpwned.com/",
      "licence": "CC BY 4.0"
    },
    {
      "source": "CVE Program (CVE records)",
      "url": "https://www.cve.org/Legal/TermsOfUse",
      "licence": "CVE Terms of Use",
      "notice": "Copyright © 1999-2026, The MITRE Corporation. CVE is a trademark and the CVE logo is a registered trademark of The MITRE Corporation.",
      "terms": "CVE Usage: MITRE hereby grants you a perpetual, worldwide, non-exclusive, no-charge, royalty-free, irrevocable copyright license to reproduce, prepare derivative works of, publicly display, publicly perform, sublicense, and distribute Common Vulnerabilities and Exposures (CVE™). Any copy you make for such purposes is authorized provided that you reproduce MITRE's copyright designation and this license in any such copy."
    },
    {
      "source": "FIRST EPSS",
      "url": "https://www.first.org/epss/",
      "licence": "free to use; FIRST requests attribution"
    }
  ],
  "record": {
    "id": "CVE-2025-40288",
    "sourceURL": "https://www.cve.org/CVERecord?id=CVE-2025-40288",
    "idYear": 2025,
    "status": "PUBLISHED",
    "publishedAt": "2025-12-06T21:51:14.440Z",
    "updatedAt": "2026-05-11T21:46:27.181Z",
    "importedAt": "2026-10-24T01:57:34.152Z",
    "snapshot": {
      "id": "cve_2026-10-24_midnight_baseline",
      "at": "2026-10-24T00:00:00.000Z",
      "source": "https://github.com/CVEProject/cvelistV5/releases/tag/cve_2026-10-24_0100Z"
    },
    "facts": {
      "title": "drm/amdgpu: Fix NULL pointer dereference in VRAM logic for APU devices",
      "summary": "In the Linux kernel, the following vulnerability has been resolved:\n\ndrm/amdgpu: Fix NULL pointer dereference in VRAM logic for APU devices\n\nPreviously, APU platforms (and other scenarios with uninitialized VRAM managers)\ntriggered a NULL pointer dereference in `ttm_resource_manager_usage()`. The root\ncause is not that the `struct ttm_resource_manager *man` pointer itself is NULL,\nbut that `man->bdev` (the backing device pointer within the manager) remains\nuninitialized (NULL) on APUs—since APUs lack dedicated VRAM and do not fully\nset up VRAM manager structures. When `ttm_resource_manager_usage()` attempts to\nacquire `man->bdev->lru_lock`, it dereferences the NULL `man->bdev`, leading to\na kernel OOPS.\n\n1. **amdgpu_cs.c**: Extend the existing bandwidth control check in\n   `amdgpu_cs_get_threshold_for_moves()` to include a check for\n   `ttm_resource_manager_used()`. If the manager is not used (uninitialized\n   `bdev`), return 0 for migration thresholds immediately—skipping VRAM-specific\n   logic that would trigger the NULL dereference.\n\n2. **amdgpu_kms.c**: Update the `AMDGPU_INFO_VRAM_USAGE` ioctl and memory info\n   reporting to use a conditional: if the manager is used, return the real VRAM\n   usage; otherwise, return 0. This avoids accessing `man->bdev` when it is\n   NULL.\n\n3. **amdgpu_virt.c**: Modify the vf2pf (virtual function to physical function)\n   data write path. Use `ttm_resource_manager_used()` to check validity: if the\n   manager is usable, calculate `fb_usage` from VRAM usage; otherwise, set\n   `fb_usage` to 0 (APUs have no discrete framebuffer to report).\n\nThis approach is more robust than APU-specific checks because it:\n- Works for all scenarios where the VRAM manager is uninitialized (not just APUs),\n- Aligns with TTM's design by using its native helper function,\n- Preserves correct behavior for discrete GPUs (which have fully initialized\n  `man->bdev` and pass the `ttm_resource_manager_used()` check).\n\nv4: use ttm_resource_manager_used(&adev->mman.vram_mgr.manager) instead of checking the adev->gmc.is_app_apu flag (Christian)",
      "affected": [
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "unaffected",
          "versions": [
            {
              "version": "d38ceaf99ed015f2a0b9af3499791bd3a3daae21",
              "status": "affected",
              "versionType": "git",
              "lessThan": "e70113b741ba253886cd71dbadfe3ea444bb2f5c"
            },
            {
              "version": "d38ceaf99ed015f2a0b9af3499791bd3a3daae21",
              "status": "affected",
              "versionType": "git",
              "lessThan": "1243e396148a65bb6c42a2b70fe43e50c16c494f"
            },
            {
              "version": "d38ceaf99ed015f2a0b9af3499791bd3a3daae21",
              "status": "affected",
              "versionType": "git",
              "lessThan": "43aa61c18a3a45042b098b7a1186ffb29364002c"
            },
            {
              "version": "d38ceaf99ed015f2a0b9af3499791bd3a3daae21",
              "status": "affected",
              "versionType": "git",
              "lessThan": "070bdce18fb12a49eb9c421e57df17d2ad29bf5f"
            },
            {
              "version": "d38ceaf99ed015f2a0b9af3499791bd3a3daae21",
              "status": "affected",
              "versionType": "git",
              "lessThan": "883f309add55060233bf11c1ea6947140372920f"
            }
          ]
        },
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "affected",
          "versions": [
            {
              "version": "4.2",
              "status": "affected"
            },
            {
              "version": "0",
              "status": "unaffected",
              "versionType": "semver",
              "lessThan": "4.2"
            },
            {
              "version": "6.1.159",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "6.1.*"
            },
            {
              "version": "6.6.117",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "6.6.*"
            },
            {
              "version": "6.12.59",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "6.12.*"
            },
            {
              "version": "6.17.9",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "6.17.*"
            },
            {
              "version": "6.18",
              "status": "unaffected",
              "versionType": "original_commit_for_fix",
              "lessThanOrEqual": "*"
            }
          ]
        }
      ]
    }
  }
}