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CVE-2026-89828

Full vulnerability record from the local CVENow database.

Description

In the Linux kernel, the following vulnerability has been resolved: drm/amdgpu: Fix init ordering in amdgpu_vram_mgr_init() drmm_cgroup_register_region() is called before INIT_LIST_HEAD() and gpu_buddy_init() in amdgpu_vram_mgr_init(). If it fails, the function returns early and bypasses those initializations. Since adev->mman.initialized is set to true before amdgpu_vram_mgr_init() is called, a failure triggers amdgpu_ttm_fini(), which calls amdgpu_vram_mgr_fini(), which then: - Calls list_for_each_entry_safe() on reservations_pending and reserved_pages, whose list_head::next pointers are zero-initialized (NULL). The loop does not recognize them as empty and dereferences NULL. - Calls gpu_buddy_fini(), which iterates free_trees[] unconditionally via for_each_free_tree(). Since mm->free_trees is NULL (never allocated), this dereferences NULL. Both result in a kernel panic on the module load error path. Fix by moving drmm_cgroup_register_region() to after the list and buddy allocator are fully initialized, so the teardown path is safe to run.

Severity
Not scored
CVSS score
Not available
Vulnerability status
Received
Source identifier
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Published
2026-09-16 11:16:49.493000
Last modified
2026-10-19 09:18:26.770000
View original CVE JSON
{
  "id": "CVE-2026-89828",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "published": "2026-09-16T11:16:49.493",
  "lastModified": "2026-10-19T09:18:26.770",
  "vulnStatus": "Received",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\ndrm/amdgpu: Fix init ordering in amdgpu_vram_mgr_init()\n\ndrmm_cgroup_register_region() is called before INIT_LIST_HEAD() and\ngpu_buddy_init() in amdgpu_vram_mgr_init(). If it fails, the function\nreturns early and bypasses those initializations.\n\nSince adev->mman.initialized is set to true before amdgpu_vram_mgr_init()\nis called, a failure triggers amdgpu_ttm_fini(), which calls\namdgpu_vram_mgr_fini(), which then:\n\n - Calls list_for_each_entry_safe() on reservations_pending and\n   reserved_pages, whose list_head::next pointers are zero-initialized\n   (NULL). The loop does not recognize them as empty and dereferences NULL.\n\n - Calls gpu_buddy_fini(), which iterates free_trees[] unconditionally\n   via for_each_free_tree(). Since mm->free_trees is NULL\n   (never allocated), this dereferences NULL.\n\nBoth result in a kernel panic on the module load error path.\n\nFix by moving drmm_cgroup_register_region() to after the list and buddy\nallocator are fully initialized, so the teardown path is safe to run."
    }
  ],
  "affected": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "affectedData": [
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "unaffected",
          "programFiles": [
            "drivers/gpu/drm/amd/amdgpu/amdgpu_vram_mgr.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "2b624a2c18656ea32e0849e7bc0018ba3c97ca64",
              "lessThan": "e184e46ca1ba652ab8053a10a51b39aad06d3f5c",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "2b624a2c18656ea32e0849e7bc0018ba3c97ca64",
              "lessThan": "3e234c6face8651045f46895dfe9c086ea64f03b",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "2b624a2c18656ea32e0849e7bc0018ba3c97ca64",
              "lessThan": "e773798e14ac0aea54ca9676083b91f445e5bc59",
              "versionType": "git",
              "status": "affected"
            }
          ]
        },
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "affected",
          "programFiles": [
            "drivers/gpu/drm/amd/amdgpu/amdgpu_vram_mgr.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "6.14",
              "status": "affected"
            },
            {
              "version": "0",
              "lessThan": "6.14",
              "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": {},
  "references": [
    {
      "url": "https://git.kernel.org/stable/c/3e234c6face8651045f46895dfe9c086ea64f03b",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/e184e46ca1ba652ab8053a10a51b39aad06d3f5c",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/e773798e14ac0aea54ca9676083b91f445e5bc59",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ]
}