{"api_version":"1","generated_at":"2026-09-11T21:38:11+00:00","cve":"CVE-2026-89758","urls":{"html":"https://cve.report/CVE-2026-89758","api":"https://cve.report/api/cve/CVE-2026-89758.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-89758","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-89758"},"summary":{"title":"mm/mempolicy: skip non-present PMDs when queueing folios","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nmm/mempolicy: skip non-present PMDs when queueing folios\n\nPatch series \"mm: handle device-private PMDs in walk callbacks\", v3.\n\nSince commit 368076f52ebe (\"mm/huge_memory: add device-private THP support\nto PMD operations\") a PMD may hold a device-private swap entry whenever an\nHMM-based GPU driver migrates an anonymous THP folio to device memory via\nmigrate_vma_pages().\n\npmd_trans_huge_lock() succeeds for such PMDs (pmd_is_huge() returns true\nfor any non-present, non-none huge PMD), so several MM walk callbacks that\nused to assume present THP or migration entry are now reachable with a\ndevice-private PMD.  The results range from a VM_BUG_ON() firing on debug\nkernels, to an oops on a bogus vmemmap dereference, to silently isolating\nan unrelated live folio from LRU in the aliasing case.\n\n\nThis patch (of 3):\n\nqueue_folios_pmd() is called under pmd_trans_huge_lock(), whose\npmd_is_huge() check returns true for any non-present, non-none PMD\nsoftleaf.  Passing such a PMD to pmd_folio() treats the softleaf encoding\nas a hardware PFN and can return a bogus folio pointer.\n\nMirror queue_folios_pte_range(): handle non-present entries before looking\nup a folio.  Keep migration entries counted as failures, but skip other\nnon-present PMDs such as device-private entries.\n\nPotential trigger: an HMM-based GPU driver migrates an anonymous THP folio\nto device memory via migrate_vma_pages(), leaving a device-private PMD. \nUserspace then calls mbind(), migrate_pages() or set_mempolicy_home_node()\non that range.","state":"PUBLISHED","assigner":"Linux","published_at":"2026-09-11 20:20:06","updated_at":"2026-09-11 20:20:06"},"problem_types":[],"metrics":[],"references":[{"url":"https://git.kernel.org/stable/c/2858b4027f491e6fdb8ee2d8923798b619bf2791","name":"https://git.kernel.org/stable/c/2858b4027f491e6fdb8ee2d8923798b619bf2791","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/3d927093b2add7ced588a926c3dc5d7a83f18596","name":"https://git.kernel.org/stable/c/3d927093b2add7ced588a926c3dc5d7a83f18596","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-89758","name":"CVE Program record","refsource":"CVE.ORG","tags":["canonical"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-89758","name":"NVD vulnerability detail","refsource":"NVD","tags":["canonical","analysis"]}],"affected":[{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 368076f52ebeecd33e10a9f80905d7508b6b6149 3d927093b2add7ced588a926c3dc5d7a83f18596 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 368076f52ebeecd33e10a9f80905d7508b6b6149 2858b4027f491e6fdb8ee2d8923798b619bf2791 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 6.19","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.19 semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.2.4 7.2.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.3-rc1 * original_commit_for_fix","platforms":[]}],"timeline":[],"solutions":[],"workarounds":[],"exploits":[],"credits":[],"nvd_cpes":[],"vendor_comments":[],"enrichments":{"kev":null,"epss":null,"legacy_qids":[]},"source_records":{"cve_program":{"containers":{"cna":{"affected":[{"defaultStatus":"unaffected","product":"Linux","programFiles":["mm/mempolicy.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"lessThan":"3d927093b2add7ced588a926c3dc5d7a83f18596","status":"affected","version":"368076f52ebeecd33e10a9f80905d7508b6b6149","versionType":"git"},{"lessThan":"2858b4027f491e6fdb8ee2d8923798b619bf2791","status":"affected","version":"368076f52ebeecd33e10a9f80905d7508b6b6149","versionType":"git"}]},{"defaultStatus":"affected","product":"Linux","programFiles":["mm/mempolicy.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"status":"affected","version":"6.19"},{"lessThan":"6.19","status":"unaffected","version":"0","versionType":"semver"},{"lessThanOrEqual":"7.2.*","status":"unaffected","version":"7.2.4","versionType":"semver"},{"lessThanOrEqual":"*","status":"unaffected","version":"7.3-rc1","versionType":"original_commit_for_fix"}]}],"cpeApplicability":[{"nodes":[{"cpeMatch":[{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.2.4","versionStartIncluding":"6.19","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.3-rc1","versionStartIncluding":"6.19","vulnerable":true}],"negate":false,"operator":"OR"}]}],"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nmm/mempolicy: skip non-present PMDs when queueing folios\n\nPatch series \"mm: handle device-private PMDs in walk callbacks\", v3.\n\nSince commit 368076f52ebe (\"mm/huge_memory: add device-private THP support\nto PMD operations\") a PMD may hold a device-private swap entry whenever an\nHMM-based GPU driver migrates an anonymous THP folio to device memory via\nmigrate_vma_pages().\n\npmd_trans_huge_lock() succeeds for such PMDs (pmd_is_huge() returns true\nfor any non-present, non-none huge PMD), so several MM walk callbacks that\nused to assume present THP or migration entry are now reachable with a\ndevice-private PMD.  The results range from a VM_BUG_ON() firing on debug\nkernels, to an oops on a bogus vmemmap dereference, to silently isolating\nan unrelated live folio from LRU in the aliasing case.\n\n\nThis patch (of 3):\n\nqueue_folios_pmd() is called under pmd_trans_huge_lock(), whose\npmd_is_huge() check returns true for any non-present, non-none PMD\nsoftleaf.  Passing such a PMD to pmd_folio() treats the softleaf encoding\nas a hardware PFN and can return a bogus folio pointer.\n\nMirror queue_folios_pte_range(): handle non-present entries before looking\nup a folio.  Keep migration entries counted as failures, but skip other\nnon-present PMDs such as device-private entries.\n\nPotential trigger: an HMM-based GPU driver migrates an anonymous THP folio\nto device memory via migrate_vma_pages(), leaving a device-private PMD. \nUserspace then calls mbind(), migrate_pages() or set_mempolicy_home_node()\non that range."}],"providerMetadata":{"dateUpdated":"2026-09-11T19:47:00.562Z","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux"},"references":[{"url":"https://git.kernel.org/stable/c/3d927093b2add7ced588a926c3dc5d7a83f18596"},{"url":"https://git.kernel.org/stable/c/2858b4027f491e6fdb8ee2d8923798b619bf2791"}],"title":"mm/mempolicy: skip non-present PMDs when queueing folios","x_generator":{"engine":"bippy-1.2.0"}}},"cveMetadata":{"assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","assignerShortName":"Linux","cveId":"CVE-2026-89758","datePublished":"2026-09-11T19:47:00.562Z","dateReserved":"2026-09-11T19:38:34.763Z","dateUpdated":"2026-09-11T19:47:00.562Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"},"nvd":{"publishedDate":"2026-09-11 20:20:06","lastModifiedDate":"2026-09-11 20:20:06","problem_types":[],"metrics":[],"configurations":[]},"legacy_mitre":{"record":{"CveYear":"2026","CveId":"89758","Ordinal":"1","Title":"mm/mempolicy: skip non-present PMDs when queueing folios","CVE":"CVE-2026-89758","Year":"2026"},"notes":[{"CveYear":"2026","CveId":"89758","Ordinal":"1","NoteData":"In the Linux kernel, the following vulnerability has been resolved:\n\nmm/mempolicy: skip non-present PMDs when queueing folios\n\nPatch series \"mm: handle device-private PMDs in walk callbacks\", v3.\n\nSince commit 368076f52ebe (\"mm/huge_memory: add device-private THP support\nto PMD operations\") a PMD may hold a device-private swap entry whenever an\nHMM-based GPU driver migrates an anonymous THP folio to device memory via\nmigrate_vma_pages().\n\npmd_trans_huge_lock() succeeds for such PMDs (pmd_is_huge() returns true\nfor any non-present, non-none huge PMD), so several MM walk callbacks that\nused to assume present THP or migration entry are now reachable with a\ndevice-private PMD.  The results range from a VM_BUG_ON() firing on debug\nkernels, to an oops on a bogus vmemmap dereference, to silently isolating\nan unrelated live folio from LRU in the aliasing case.\n\n\nThis patch (of 3):\n\nqueue_folios_pmd() is called under pmd_trans_huge_lock(), whose\npmd_is_huge() check returns true for any non-present, non-none PMD\nsoftleaf.  Passing such a PMD to pmd_folio() treats the softleaf encoding\nas a hardware PFN and can return a bogus folio pointer.\n\nMirror queue_folios_pte_range(): handle non-present entries before looking\nup a folio.  Keep migration entries counted as failures, but skip other\nnon-present PMDs such as device-private entries.\n\nPotential trigger: an HMM-based GPU driver migrates an anonymous THP folio\nto device memory via migrate_vma_pages(), leaving a device-private PMD. \nUserspace then calls mbind(), migrate_pages() or set_mempolicy_home_node()\non that range.","Type":"Description","Title":"mm/mempolicy: skip non-present PMDs when queueing folios"}]}}}