{
    "dataType": "CVE_RECORD",
    "dataVersion": "5.1",
    "cveMetadata": {
        "cveId": "CVE-2024-40950",
        "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "state": "PUBLISHED",
        "assignerShortName": "Linux",
        "dateReserved": "2024-07-12T12:17:45.591Z",
        "datePublished": "2024-07-12T12:31:54.815Z",
        "dateUpdated": "2024-09-11T17:34:24.864Z"
    },
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                "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
                "shortName": "Linux",
                "dateUpdated": "2024-07-15T06:52:03.363Z"
            },
            "descriptions": [
                {
                    "lang": "en",
                    "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nmm: huge_memory: fix misused mapping_large_folio_support() for anon folios\n\nWhen I did a large folios split test, a WARNING \"[ 5059.122759][ T166]\nCannot split file folio to non-0 order\" was triggered.  But the test cases\nare only for anonmous folios.  while mapping_large_folio_support() is only\nreasonable for page cache folios.\n\nIn split_huge_page_to_list_to_order(), the folio passed to\nmapping_large_folio_support() maybe anonmous folio.  The folio_test_anon()\ncheck is missing.  So the split of the anonmous THP is failed.  This is\nalso the same for shmem_mapping().  We'd better add a check for both.  But\nthe shmem_mapping() in __split_huge_page() is not involved, as for\nanonmous folios, the end parameter is set to -1, so (head[i].index >= end)\nis always false.  shmem_mapping() is not called.\n\nAlso add a VM_WARN_ON_ONCE() in mapping_large_folio_support() for anon\nmapping, So we can detect the wrong use more easily.\n\nTHP folios maybe exist in the pagecache even the file system doesn't\nsupport large folio, it is because when CONFIG_TRANSPARENT_HUGEPAGE is\nenabled, khugepaged will try to collapse read-only file-backed pages to\nTHP.  But the mapping does not actually support multi order large folios\nproperly.\n\nUsing /sys/kernel/debug/split_huge_pages to verify this, with this patch,\nlarge anon THP is successfully split and the warning is ceased."
                }
            ],
            "affected": [
                {
                    "product": "Linux",
                    "vendor": "Linux",
                    "defaultStatus": "unaffected",
                    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                    "programFiles": [
                        "include/linux/pagemap.h",
                        "mm/huge_memory.c"
                    ],
                    "versions": [
                        {
                            "version": "c010d47f107f",
                            "lessThan": "5df493a99fcf",
                            "status": "affected",
                            "versionType": "git"
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                            "version": "c010d47f107f",
                            "lessThan": "6a50c9b512f7",
                            "status": "affected",
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                        }
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                    "vendor": "Linux",
                    "defaultStatus": "affected",
                    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                    "programFiles": [
                        "include/linux/pagemap.h",
                        "mm/huge_memory.c"
                    ],
                    "versions": [
                        {
                            "version": "6.9",
                            "status": "affected"
                        },
                        {
                            "version": "0",
                            "lessThan": "6.9",
                            "status": "unaffected",
                            "versionType": "custom"
                        },
                        {
                            "version": "6.9.7",
                            "lessThanOrEqual": "6.9.*",
                            "status": "unaffected",
                            "versionType": "custom"
                        },
                        {
                            "version": "6.10",
                            "lessThanOrEqual": "*",
                            "status": "unaffected",
                            "versionType": "original_commit_for_fix"
                        }
                    ]
                }
            ],
            "references": [
                {
                    "url": "https://git.kernel.org/stable/c/5df493a99fcf887133cf01d23cd4bebb6d385d3c"
                },
                {
                    "url": "https://git.kernel.org/stable/c/6a50c9b512f7734bc356f4bd47885a6f7c98491a"
                }
            ],
            "title": "mm: huge_memory: fix misused mapping_large_folio_support() for anon folios",
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                    "dateUpdated": "2024-08-02T04:39:55.883Z"
                },
                "title": "CVE Program Container",
                "references": [
                    {
                        "url": "https://git.kernel.org/stable/c/5df493a99fcf887133cf01d23cd4bebb6d385d3c",
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                            "type": "ssvc",
                            "content": {
                                "id": "CVE-2024-40950",
                                "role": "CISA Coordinator",
                                "options": [
                                    {
                                        "Exploitation": "none"
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