ghsa-q9r2-5479-5hm7
Vulnerability from github
In the Linux kernel, the following vulnerability has been resolved:
mm: turn folio_test_hugetlb into a PageType
The current folio_test_hugetlb() can be fooled by a concurrent folio split into returning true for a folio which has never belonged to hugetlbfs. This can't happen if the caller holds a refcount on it, but we have a few places (memory-failure, compaction, procfs) which do not and should not take a speculative reference.
Since hugetlb pages do not use individual page mapcounts (they are always fully mapped and use the entire_mapcount field to record the number of mappings), the PageType field is available now that page_mapcount() ignores the value in this field.
In compaction and with CONFIG_DEBUG_VM enabled, the current implementation can result in an oops, as reported by Luis. This happens since 9c5ccf2db04b ("mm: remove HUGETLB_PAGE_DTOR") effectively added some VM_BUG_ON() checks in the PageHuge() testing path.
[willy@infradead.org: update vmcoreinfo] Link: https://lkml.kernel.org/r/ZgGZUvsdhaT1Va-T@casper.infradead.org
{
"affected": [],
"aliases": [
"CVE-2024-35993"
],
"database_specific": {
"cwe_ids": [],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2024-05-20T10:15:13Z",
"severity": null
},
"details": "In the Linux kernel, the following vulnerability has been resolved:\n\nmm: turn folio_test_hugetlb into a PageType\n\nThe current folio_test_hugetlb() can be fooled by a concurrent folio split\ninto returning true for a folio which has never belonged to hugetlbfs. \nThis can\u0027t happen if the caller holds a refcount on it, but we have a few\nplaces (memory-failure, compaction, procfs) which do not and should not\ntake a speculative reference.\n\nSince hugetlb pages do not use individual page mapcounts (they are always\nfully mapped and use the entire_mapcount field to record the number of\nmappings), the PageType field is available now that page_mapcount()\nignores the value in this field.\n\nIn compaction and with CONFIG_DEBUG_VM enabled, the current implementation\ncan result in an oops, as reported by Luis. This happens since 9c5ccf2db04b\n(\"mm: remove HUGETLB_PAGE_DTOR\") effectively added some VM_BUG_ON() checks\nin the PageHuge() testing path.\n\n[willy@infradead.org: update vmcoreinfo]\n Link: https://lkml.kernel.org/r/ZgGZUvsdhaT1Va-T@casper.infradead.org",
"id": "GHSA-q9r2-5479-5hm7",
"modified": "2024-05-20T12:30:29Z",
"published": "2024-05-20T12:30:29Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2024-35993"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/2431b5f2650dfc47ce782d1ca7b02d6b3916976f"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/9fdcc5b6359dfdaa52a55033bf50e2cedd66eb32"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/d99e3140a4d33e26066183ff727d8f02f56bec64"
}
],
"schema_version": "1.4.0",
"severity": []
}