{"cve":"CVE-2024-57883","nvd":{"published":"2025-01-15T13:15:12.637","modified":"2026-10-15T22:18:03.883","status":"Modified","description":"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.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","score":5.5},"cwes":[],"references":["https://git.kernel.org/stable/c/02333ac1c35370517a19a4a131332a9690c6a5c7","https://git.kernel.org/stable/c/2e31443a0d18ae43b9d29e02bf0563f07772193d","https://git.kernel.org/stable/c/56b274473d6e7e7375f2d0a2b4aca11d67c6b52f","https://git.kernel.org/stable/c/59d9094df3d79443937add8700b2ef1a866b1081","https://git.kernel.org/stable/c/8410996eb6fea116fe1483ed977aacf580eee7b4"],"products":["linux:linux_kernel"],"source":"nvd","synced_at":"2026-10-19T21:58:20.756570362+00:00"},"epss":{"cve":"CVE-2024-57883","score":0.00217,"percentile":0.12049,"date":"2026-10-25"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}