{
    "data_version": "4.0",
    "data_type": "CVE",
    "data_format": "MITRE",
    "CVE_data_meta": {
        "ID": "CVE-2024-49964",
        "ASSIGNER": "cve@kernel.org",
        "STATE": "PUBLIC"
    },
    "description": {
        "description_data": [
            {
                "lang": "eng",
                "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nmm/hugetlb: fix memfd_pin_folios free_huge_pages leak\n\nmemfd_pin_folios followed by unpin_folios fails to restore free_huge_pages\nif the pages were not already faulted in, because the folio refcount for\npages created by memfd_alloc_folio never goes to 0.  memfd_pin_folios\nneeds another folio_put to undo the folio_try_get below:\n\nmemfd_alloc_folio()\n  alloc_hugetlb_folio_nodemask()\n    dequeue_hugetlb_folio_nodemask()\n      dequeue_hugetlb_folio_node_exact()\n        folio_ref_unfreeze(folio, 1);    ; adds 1 refcount\n  folio_try_get()                        ; adds 1 refcount\n  hugetlb_add_to_page_cache()            ; adds 512 refcount (on x86)\n\nWith the fix, after memfd_pin_folios + unpin_folios, the refcount for the\n(unfaulted) page is 512, which is correct, as the refcount for a faulted\nunpinned page is 513."
            }
        ]
    },
    "problemtype": {
        "problemtype_data": [
            {
                "description": [
                    {
                        "lang": "eng",
                        "value": "n/a"
                    }
                ]
            }
        ]
    },
    "affects": {
        "vendor": {
            "vendor_data": [
                {
                    "vendor_name": "Linux",
                    "product": {
                        "product_data": [
                            {
                                "product_name": "Linux",
                                "version": {
                                    "version_data": [
                                        {
                                            "version_affected": "<",
                                            "version_name": "89c1905d9c14",
                                            "version_value": "59e081ff2e91"
                                        },
                                        {
                                            "version_value": "not down converted",
                                            "x_cve_json_5_version_data": {
                                                "versions": [
                                                    {
                                                        "version": "6.11",
                                                        "status": "affected"
                                                    },
                                                    {
                                                        "version": "0",
                                                        "lessThan": "6.11",
                                                        "status": "unaffected",
                                                        "versionType": "semver"
                                                    },
                                                    {
                                                        "version": "6.11.3",
                                                        "lessThanOrEqual": "6.11.*",
                                                        "status": "unaffected",
                                                        "versionType": "semver"
                                                    },
                                                    {
                                                        "version": "6.12",
                                                        "lessThanOrEqual": "*",
                                                        "status": "unaffected",
                                                        "versionType": "original_commit_for_fix"
                                                    }
                                                ],
                                                "defaultStatus": "affected"
                                            }
                                        }
                                    ]
                                }
                            }
                        ]
                    }
                }
            ]
        }
    },
    "references": {
        "reference_data": [
            {
                "url": "https://git.kernel.org/stable/c/59e081ff2e91bbf19b8c1ecb75b031f778858383",
                "refsource": "MISC",
                "name": "https://git.kernel.org/stable/c/59e081ff2e91bbf19b8c1ecb75b031f778858383"
            },
            {
                "url": "https://git.kernel.org/stable/c/c56b6f3d801d7ec8965993342bdd9e2972b6cb8e",
                "refsource": "MISC",
                "name": "https://git.kernel.org/stable/c/c56b6f3d801d7ec8965993342bdd9e2972b6cb8e"
            }
        ]
    },
    "generator": {
        "engine": "bippy-8e903de6a542"
    }
}