{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2024-57883", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2025-01-11T14:45:42.024Z", "datePublished": "2025-01-15T13:05:36.352Z", "dateUpdated": "2026-08-05T11:46:45.519Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-05T11:46:45.519Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nmm: hugetlb: independent PMD page table shared count\n\nThe folio refcount may be increased unexpectly through try_get_folio() by\ncaller such as split_huge_pages. In huge_pmd_unshare(), we use refcount\nto check whether a pmd page table is shared. The check is incorrect if\nthe refcount is increased by the above caller, and this can cause the page\ntable leaked:\n\n BUG: Bad page state in process sh pfn:109324\n page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x66 pfn:0x109324\n flags: 0x17ffff800000000(node=0|zone=2|lastcpupid=0xfffff)\n page_type: f2(table)\n raw: 017ffff800000000 0000000000000000 0000000000000000 0000000000000000\n raw: 0000000000000066 0000000000000000 00000000f2000000 0000000000000000\n page dumped because: nonzero mapcount\n ...\n CPU: 31 UID: 0 PID: 7515 Comm: sh Kdump: loaded Tainted: G B 6.13.0-rc2master+ #7\n Tainted: [B]=BAD_PAGE\n Hardware name: QEMU KVM Virtual Machine, BIOS 0.0.0 02/06/2015\n Call trace:\n show_stack+0x20/0x38 (C)\n dump_stack_lvl+0x80/0xf8\n dump_stack+0x18/0x28\n bad_page+0x8c/0x130\n free_page_is_bad_report+0xa4/0xb0\n free_unref_page+0x3cc/0x620\n __folio_put+0xf4/0x158\n split_huge_pages_all+0x1e0/0x3e8\n split_huge_pages_write+0x25c/0x2d8\n full_proxy_write+0x64/0xd8\n vfs_write+0xcc/0x280\n ksys_write+0x70/0x110\n __arm64_sys_write+0x24/0x38\n invoke_syscall+0x50/0x120\n el0_svc_common.constprop.0+0xc8/0xf0\n do_el0_svc+0x24/0x38\n el0_svc+0x34/0x128\n el0t_64_sync_handler+0xc8/0xd0\n el0t_64_sync+0x190/0x198\n\nThe issue may be triggered by damon, offline_page, page_idle, etc, which\nwill increase the refcount of page table.\n\n1. The page table itself will be discarded after reporting the\n \"nonzero mapcount\".\n\n2. The HugeTLB page mapped by the page table miss freeing since we\n treat the page table as shared and a shared page table will not be\n unmapped.\n\nFix it by introducing independent PMD page table shared count. As\ndescribed by comment, pt_index/pt_mm/pt_frag_refcount are used for s390\ngmap, x86 pgds and powerpc, pt_share_count is used for x86/arm64/riscv\npmds, so we can reuse the field as pt_share_count." } ], "metrics": [ { "cvssV3_1": { "version": "3.1", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H", "baseScore": 7.8, "baseSeverity": "HIGH" }, "scenarios": [ { "lang": "en", "value": "AV:L - The vulnerable path is reached through local memory-management syscalls (mmap/munmap/mremap/mprotect on hugetlbfs or MAP_HUGETLB) that drive huge_pmd_unshare() from __unmap_hugepage_range(), move_hugetlb_page_tables() and hugetlb_change_protection(). No network or remote-peer data reaches this code.\nAC:L - The attacker drives both sides of the window: they repeatedly set up and tear down hugetlb mappings while concurrently issuing GUP-fast operations (O_DIRECT, io_uring, vmsplice) whose try_get_folio() speculative pin is exactly the refcount inflation the commit names, and the attempt can be retried without bound until it lands. On the very common cloud-guest configuration, virtio-mem/balloon hot-unplug runs do_migrate_range(), which folio_try_get()s every PFN with no LRU pre-check, widening the window enormously.\nPR:L - Every operation the attacker performs — creating a PUD-aligned MAP_SHARED hugetlbfs mapping and then unmapping, remapping or mprotecting it — is available to any unprivileged local user on hosts where hugepages are provisioned (databases, KVM hosts, HPC and container nodes routinely make /dev/hugepages group-accessible), and huge_pmd_unshare() performs no capability check.\nUI:N - The attacker issues the syscalls itself in a loop; no action by any other user or administrator is needed to complete the attack.\nS:U - The corrupted page tables and leaked hugetlb folios belong to the same kernel security authority; no VM, IOMMU or sandbox boundary is crossed even though the outcome is full kernel compromise.\nC:H - For PUD_SIZE hugetlb the refcount wrongly dropped belongs to the still-installed PUD page table page, and because free_pages_prepare() only runs the bad-page check under is_check_pages_enabled() (off on production kernels), that live page table is handed back to the buddy allocator and reallocated to attacker-controlled data, giving forged PUD entries and arbitrary physical memory read.\nI:H - The same freed-but-live page table gives the attacker write control over PUD entries, mapping arbitrary physical memory writable into their address space — an arbitrary kernel write and control-flow-hijack primitive; even short of that, mm_dec_nr_pmds() underflow and skipped unmapping corrupt kernel page-table accounting and mapcount state.\nA:H - Every triggering instance permanently leaks the PMD/PUD page table plus all hugetlb folios it mapped (they are never unmapped, so their mapcount and refcount stay pinned until reboot), repeatably exhausting the scarce pre-reserved hugetlb pool; on debug or panic_on_taint kernels it also produces the reported \"BUG: Bad page state\" with kernel taint, and freeing a live page table into the allocator crashes the system." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "include/linux/mm.h", "include/linux/mm_types.h", "mm/hugetlb.c" ], "versions": [ { "version": "39dde65c9940c97fcd178a3d2b1c57ed8b7b68aa", "lessThan": "94b4b41d0cdf5cfd4d4325bc0e6e9e0d0e996133", "status": "affected", "versionType": "git" }, { "version": "39dde65c9940c97fcd178a3d2b1c57ed8b7b68aa", "lessThan": "8410996eb6fea116fe1483ed977aacf580eee7b4", "status": "affected", "versionType": "git" }, { "version": "39dde65c9940c97fcd178a3d2b1c57ed8b7b68aa", "lessThan": "02333ac1c35370517a19a4a131332a9690c6a5c7", "status": "affected", "versionType": "git" }, { "version": "39dde65c9940c97fcd178a3d2b1c57ed8b7b68aa", "lessThan": "56b274473d6e7e7375f2d0a2b4aca11d67c6b52f", "status": "affected", "versionType": "git" }, { "version": "39dde65c9940c97fcd178a3d2b1c57ed8b7b68aa", "lessThan": "2e31443a0d18ae43b9d29e02bf0563f07772193d", "status": "affected", "versionType": "git" }, { "version": "39dde65c9940c97fcd178a3d2b1c57ed8b7b68aa", "lessThan": "59d9094df3d79443937add8700b2ef1a866b1081", "status": "affected", "versionType": "git" } ] }, { "product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "include/linux/mm.h", "include/linux/mm_types.h", "mm/hugetlb.c" ], "versions": [ { "version": "2.6.20", "status": "affected" }, { "version": "0", "lessThan": "2.6.20", "status": "unaffected", "versionType": "semver" }, { "version": "5.10.239", "lessThanOrEqual": "5.10.*", "status": "unaffected", "versionType": "semver" }, { "version": "5.15.186", "lessThanOrEqual": "5.15.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.1.142", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.6.72", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.12.9", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.13", "lessThanOrEqual": "*", "status": "unaffected", "versionType": "original_commit_for_fix" } ] } ], "cpeApplicability": [ { "nodes": [ { "operator": "OR", "negate": false, "cpeMatch": [ { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.20", "versionEndExcluding": "5.10.239" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.20", "versionEndExcluding": "5.15.186" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.20", "versionEndExcluding": "6.1.142" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.20", "versionEndExcluding": "6.6.72" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.20", "versionEndExcluding": "6.12.9" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.20", "versionEndExcluding": "6.13" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/94b4b41d0cdf5cfd4d4325bc0e6e9e0d0e996133" }, { "url": "https://git.kernel.org/stable/c/8410996eb6fea116fe1483ed977aacf580eee7b4" }, { "url": "https://git.kernel.org/stable/c/02333ac1c35370517a19a4a131332a9690c6a5c7" }, { "url": "https://git.kernel.org/stable/c/56b274473d6e7e7375f2d0a2b4aca11d67c6b52f" }, { "url": "https://git.kernel.org/stable/c/2e31443a0d18ae43b9d29e02bf0563f07772193d" }, { "url": "https://git.kernel.org/stable/c/59d9094df3d79443937add8700b2ef1a866b1081" } ], "title": "mm: hugetlb: independent PMD page table shared count", "x_generator": { "engine": "bippy-1.2.0" } }, "adp": [ { "title": "CVE Program Container", "references": [ { "url": "https://lists.debian.org/debian-lts-announce/2025/10/msg00008.html" }, { "url": "https://lists.debian.org/debian-lts-announce/2025/10/msg00007.html" } ], "providerMetadata": { "orgId": "af854a3a-2127-422b-91ae-364da2661108", "shortName": "CVE", "dateUpdated": "2025-11-03T17:31:29.588Z" } } ] } }