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CVE-2026-93216

Estado: RecibidaSin puntuar—

In the Linux kernel, the following vulnerability has been resolved:

mm/page_owner: use memcg_data snapshot to avoid TOCTOU in print_page_owner_memcg()

print_page_owner_memcg() reads page->memcg_data via READ_ONCE() at the start to guard against tail pages and NULL data. However, it later re-reads page->memcg_data locklessly in two places:

1: page_memcg_check(page)

If the page is concurrently freed and reallocated as a THP tail page or slab page between these calls, the VM_BUG_ON assertions can trigger on CONFIG_DEBUG_VM=y builds, crashing the kernel.

Fix both TOCTOU issues by using the memcg_data snapshot throughout.

Detalles técnicos trazas, registros y código del informe original
2: PageMemcgKmem(page) (via folio_memcg_kmem(), which includes
   VM_BUG_ON assertions for tail pages and MEMCG_DATA_OBJEXTS)

CVSS

NVD no ha asignado puntuación CVSS a esta CVE (habitual desde el cambio de política de abril de 2026).

Probabilidad de explotación (EPSS)

EPSS (Exploit Prediction Scoring System, de FIRST) estima la probabilidad de que una vulnerabilidad sea explotada en 30 días. Complementa a CVSS (impacto) y a CISA KEV (explotación confirmada).

Tecnologías afectadas (1)

⚠ Inferidas por IA a partir de la descripción — NVD aún no ha analizado esta CVE; no son CPE verificados.

Linux — Linux KernelAI

Referencias

JSON original (NVD)

Mostrar
{
  "id": "CVE-2026-93216",
  "cveTags": [],
  "metrics": {},
  "affected": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "affectedData": [
        {
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "product": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "fcf8935832b86d3437f00e732c6d0d4d2819d6a9",
              "lessThan": "46761406e14381dc35f498c247a87565b87ea2ef",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "fcf8935832b86d3437f00e732c6d0d4d2819d6a9",
              "lessThan": "90f095b816e25c6a9e4446d299bac5007fdcb3df",
              "versionType": "git"
            }
          ],
          "programFiles": [
            "mm/page_owner.c"
          ],
          "defaultStatus": "unaffected"
        },
        {
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "product": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "5.18"
            },
            {
              "status": "unaffected",
              "version": "0",
              "lessThan": "5.18",
              "versionType": "semver"
            },
            {
              "status": "unaffected",
              "version": "7.2.4",
              "versionType": "semver",
              "lessThanOrEqual": "7.2.*"
            },
            {
              "status": "unaffected",
              "version": "7.3-rc1",
              "versionType": "original_commit_for_fix",
              "lessThanOrEqual": "*"
            }
          ],
          "programFiles": [
            "mm/page_owner.c"
          ],
          "defaultStatus": "affected"
        }
      ]
    }
  ],
  "published": "2026-09-24T16:17:16.670",
  "references": [
    {
      "url": "https://git.kernel.org/stable/c/46761406e14381dc35f498c247a87565b87ea2ef",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/90f095b816e25c6a9e4446d299bac5007fdcb3df",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ],
  "vulnStatus": "Received",
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nmm/page_owner: use memcg_data snapshot to avoid TOCTOU in print_page_owner_memcg()\n\nprint_page_owner_memcg() reads page->memcg_data via READ_ONCE() at the\nstart to guard against tail pages and NULL data.  However, it later\nre-reads page->memcg_data locklessly in two places:\n\n1: page_memcg_check(page)\n\n2: PageMemcgKmem(page) (via folio_memcg_kmem(), which includes\n   VM_BUG_ON assertions for tail pages and MEMCG_DATA_OBJEXTS)\n\nIf the page is concurrently freed and reallocated as a THP tail page or\nslab page between these calls, the VM_BUG_ON assertions can trigger on\nCONFIG_DEBUG_VM=y builds, crashing the kernel.\n\nFix both TOCTOU issues by using the memcg_data snapshot throughout."
    }
  ],
  "lastModified": "2026-09-24T16:17:16.670",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}