mm/hugetlb: fix hugetlb vs. core-mm PT locking

{
  "id": "6d42c94fd054b00dceece05e796365ce211902277405d3293b51ca82dbec381c",
  "url": "https://osv.dev/vulnerability/CVE-2024-45024",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "mm/hugetlb: fix hugetlb vs. core-mm PT locking",
    "summary": "In the Linux kernel, the following vulnerability has been resolved: mm/hugetlb: fix hugetlb vs. core-mm PT locking We recently made GUP's common page table walking code to also walk hugetlb VMAs without most hugetlb special-casing, preparing for the future of having less hugetlb-specific page table walking code in the codebase. Turns out that we missed one page table locking detail: page table locking for hugetlb folios that are not mapped using a single PMD/PUD. Assume we have hugetlb folio that spans multiple PTEs (e.g., 64 KiB hugetlb folios on arm64 with 4 KiB base page size). GUP, as it walks the page tables, will perform a pte_offset_map_lock() to grab the PTE table lock. However, hugetlb that concurrently modifies these page tables would actually grab the mm->page_table_lock: with USE_SPLIT_PTE_PTLOCKS, the locks would differ. Something similar can happen right now with hugetlb folios that span multiple PMDs when USE_SPLIT_PMD_PTLOCKS. This issue can be reproduced [1], for example triggering: [ 3105.936100] ------------[ cut here ]------------ [ 3105.939323] WARNING: CPU: 31 PID: 2732 at mm/gup.c:142 try_grab_folio+0x11c/0x188 [ 3105.944634] Modules linked in: [...] [ 3105.974841] CPU: 31 PID: 2732 Comm: reproducer Not tainted 6.10.0-64.eln141.aarch64 #1 [ 3105.980406] Hardware name: QEMU KVM Virtual Machine, BIOS edk2-20240524-4.fc40 05/24/2024 [ 3105.986185] pstate: 60000005 (nZCv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--) [ 3105.991108] pc : try_grab_folio+0x11c/0x188",
    "evidence": "osv:CVE-2024-45024",
    "products": [
      {
        "name": {
          "value": "Kernel",
          "evidence": "/affected/1/package/name"
        },
        "prerequisites": [],
        "fixed_versions": [
          {
            "value": "6.10.7",
            "evidence": "/affected/1/ranges"
          }
        ],
        "affected_versions": []
      }
    ],
    "severity": "high",
    "structured": {
      "id": "CVE-2024-45024",
      "aliases": [
        "CVE-2024-45024"
      ],
      "metrics": [
        {
          "type": "CVSS_V3",
          "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
              "type": "GIT",
              "events": [
                {
                  "introduced": "9cb28da54643ad464c47585cd5866c30b0218e67"
                },
                {
                  "fixed": "7300dadba49e531af2d890ae4e34c9b115384a62"
                },
                {
                  "fixed": "5f75cfbd6bb02295ddaed48adf667b6c828ce07b"
                }
              ]
            }
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2024-45024.json"
          }
        },
        {
          "ranges": [
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "6.10.0"
                },
                {
                  "fixed": "6.10.7"
                }
              ]
            }
          ],
          "package": {
            "name": "Kernel",
            "ecosystem": "Linux"
          },
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2024-45024.json"
          }
        }
      ],
      "modified": "2026-10-28T02:30:50.709078236Z",
      "provider": "osv",
      "references": [
        "https://git.kernel.org/stable/c/5f75cfbd6bb02295ddaed48adf667b6c828ce07b",
        "https://git.kernel.org/stable/c/7300dadba49e531af2d890ae4e34c9b115384a62",
        "https://github.com/CVEProject/cvelistV5/tree/main/cves/2024/45xxx/CVE-2024-45024.json",
        "https://nvd.nist.gov/vuln/detail/CVE-2024-45024",
        "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"
      ],
      "provider_metadata": {
        "cna_assigner": "Linux",
        "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2024/45xxx/CVE-2024-45024.json"
      }
    },
    "related_cves": [
      {
        "value": "CVE-2024-45024",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 519110,
  "published_at": "2024-09-11T15:13:57.076+00:00"
}