{ "schemaVersion": 1, "attribution": [ { "source": "CISA Known Exploited Vulnerabilities", "url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog", "licence": "US government work" }, { "source": "GitHub Advisory Database", "url": "https://github.com/advisories", "licence": "CC BY 4.0" }, { "source": "Have I Been Pwned", "url": "https://haveibeenpwned.com/", "licence": "CC BY 4.0" }, { "source": "CVE Program (CVE records)", "url": "https://www.cve.org/Legal/TermsOfUse", "licence": "CVE Terms of Use", "notice": "Copyright © 1999-2026, The MITRE Corporation. CVE is a trademark and the CVE logo is a registered trademark of The MITRE Corporation.", "terms": "CVE Usage: MITRE hereby grants you a perpetual, worldwide, non-exclusive, no-charge, royalty-free, irrevocable copyright license to reproduce, prepare derivative works of, publicly display, publicly perform, sublicense, and distribute Common Vulnerabilities and Exposures (CVE™). Any copy you make for such purposes is authorized provided that you reproduce MITRE's copyright designation and this license in any such copy." }, { "source": "FIRST EPSS", "url": "https://www.first.org/epss/", "licence": "free to use; FIRST requests attribution" } ], "record": { "id": "CVE-2025-22034", "sourceURL": "https://www.cve.org/CVERecord?id=CVE-2025-22034", "idYear": 2025, "status": "PUBLISHED", "publishedAt": "2025-04-16T14:11:53.301Z", "updatedAt": "2026-08-05T11:56:06.819Z", "importedAt": "2026-10-24T01:57:29.455Z", "snapshot": { "id": "cve_2026-10-24_midnight_baseline", "at": "2026-10-24T00:00:00.000Z", "source": "https://github.com/CVEProject/cvelistV5/releases/tag/cve_2026-10-24_0100Z" }, "facts": { "title": "mm/gup: reject FOLL_SPLIT_PMD with hugetlb VMAs", "summary": "In the Linux kernel, the following vulnerability has been resolved:\n\nmm/gup: reject FOLL_SPLIT_PMD with hugetlb VMAs\n\nPatch series \"mm: fixes for device-exclusive entries (hmm)\", v2.\n\nDiscussing the PageTail() call in make_device_exclusive_range() with\nWilly, I recently discovered [1] that device-exclusive handling does not\nproperly work with THP, making the hmm-tests selftests fail if THPs are\nenabled on the system.\n\nLooking into more details, I found that hugetlb is not properly fenced,\nand I realized that something that was bugging me for longer -- how\ndevice-exclusive entries interact with mapcounts -- completely breaks\nmigration/swapout/split/hwpoison handling of these folios while they have\ndevice-exclusive PTEs.\n\nThe program below can be used to allocate 1 GiB worth of pages and making\nthem device-exclusive on a kernel with CONFIG_TEST_HMM.\n\nOnce they are device-exclusive, these folios cannot get swapped out\n(proc$pid/smaps_rollup will always indicate 1 GiB RSS no matter how much\none forces memory reclaim), and when having a memory block onlined to\nZONE_MOVABLE, trying to offline it will loop forever and complain about\nfailed migration of a page that should be movable.\n\n# echo offline > /sys/devices/system/memory/memory136/state\n# echo online_movable > /sys/devices/system/memory/memory136/state\n# ./hmm-swap &\n... wait until everything is device-exclusive\n# echo offline > /sys/devices/system/memory/memory136/state\n[ 285.193431][T14882] page: refcount:2 mapcount:0 mapping:0000000000000000\n index:0x7f20671f7 pfn:0x442b6a\n[ 285.196618][T14882] memcg:ffff888179298000\n[ 285.198085][T14882] anon flags: 0x5fff0000002091c(referenced|uptodate|\n dirty|active|owner_2|swapbacked|node=1|zone=3|lastcpupid=0x7ff)\n[ 285.201734][T14882] raw: ...\n[ 285.204464][T14882] raw: ...\n[ 285.207196][T14882] page dumped because: migration failure\n[ 285.209072][T14882] page_owner tracks the page as allocated\n[ 285.210915][T14882] page last allocated via order 0, migratetype\n Movable, gfp_mask 0x140dca(GFP_HIGHUSER_MOVABLE|__GFP_COMP|__GFP_ZERO),\n id 14926, tgid 14926 (hmm-swap), ts 254506295376, free_ts 227402023774\n[ 285.216765][T14882] post_alloc_hook+0x197/0x1b0\n[ 285.218874][T14882] get_page_from_freelist+0x76e/0x3280\n[ 285.220864][T14882] __alloc_frozen_pages_noprof+0x38e/0x2740\n[ 285.223302][T14882] alloc_pages_mpol+0x1fc/0x540\n[ 285.225130][T14882] folio_alloc_mpol_noprof+0x36/0x340\n[ 285.227222][T14882] vma_alloc_folio_noprof+0xee/0x1a0\n[ 285.229074][T14882] __handle_mm_fault+0x2b38/0x56a0\n[ 285.230822][T14882] handle_mm_fault+0x368/0x9f0\n...\n\nThis series fixes all issues I found so far. There is no easy way to fix\nwithout a bigger rework/cleanup. I have a bunch of cleanups on top (some\nprevious sent, some the result of the discussion in v1) that I will send\nout separately once this landed and I get to it.\n\nI wish we could just use some special present PROT_NONE PTEs instead of\nthese (non-present, non-none) fake-swap entries; but that just results in\nthe same problem we keep having (lack of spare PTE bits), and staring at\nother similar fake-swap entries, that ship has sailed.\n\nWith this series, make_device_exclusive() doesn't actually belong into\nmm/rmap.c anymore, but I'll leave moving that for another day.\n\nI only tested this series with the hmm-tests selftests due to lack of HW,\nso I'd appreciate some testing, especially if the interaction between two\nGPUs wanting a device-exclusive entry works as expected.\n\n\n#include \n#include \n#include \n#include \n#include \n#include \n#include \n#include \n#include \n#include \n\n#define HMM_DMIRROR_EXCLUSIVE _IOWR('H', 0x05, struct hmm_dmirror_cmd)\n\nstruct hmm_dmirror_cmd {\n\t__u64 addr;\n\t__u64 ptr;\n\t__u64 npages;\n\t__u64 cpages;\n\t__u64 faults;\n};\n\nconst size_t size = 1 * 1024 * 1024 * 1024ul;\nconst size_t chunk_size = 2 * 1024 * 1024ul;\n\nint m\n---truncated---", "affected": [ { "vendor": "Linux", "product": "Linux", "defaultStatus": "unaffected", "versions": [ { "version": "9cb28da54643ad464c47585cd5866c30b0218e67", "status": "affected", "versionType": "git", "lessThan": "2e877ff3492267def06dd50cb165dc9ab8838e7d" }, { "version": "9cb28da54643ad464c47585cd5866c30b0218e67", "status": "affected", "versionType": "git", "lessThan": "48d28417c66cce2f3b0ba773fcb6695a56eff220" }, { "version": "9cb28da54643ad464c47585cd5866c30b0218e67", "status": "affected", "versionType": "git", "lessThan": "fd900832e8440046627b60697687ab5d04398008" }, { "version": "9cb28da54643ad464c47585cd5866c30b0218e67", "status": "affected", "versionType": "git", "lessThan": "8977752c8056a6a094a279004a49722da15bace3" } ] }, { "vendor": "Linux", "product": "Linux", "defaultStatus": "affected", "versions": [ { "version": "6.10", "status": "affected" }, { "version": "0", "status": "unaffected", "versionType": "semver", "lessThan": "6.10" }, { "version": "6.12.23", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "6.12.*" }, { "version": "6.13.11", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "6.13.*" }, { "version": "6.14.2", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "6.14.*" }, { "version": "6.15", "status": "unaffected", "versionType": "original_commit_for_fix", "lessThanOrEqual": "*" } ] } ] } } }