{"id":"CVE-2026-53342","summary":"arm64: mm: call pagetable dtor when freeing hot-removed page tables","details":"In the Linux kernel, the following vulnerability has been resolved:\n\narm64: mm: call pagetable dtor when freeing hot-removed page tables\n\nSince 5e8eb9aeeda3 (\"arm64: mm: always call PTE/PMD ctor in\n__create_pgd_mapping()\") page-table allocation on ARM64 always calls\npagetable_{pte,pmd,pud,p4d}_ctor().  This sets the page_type to\nPGTY_table, increments NR_PAGETABLE and possible allocates a PTL.  However\nthe matching pagetable_dtor() calls were never added.\n\nWith DEBUG_VM enabled on kernel versions prior to v6.17 without\n2dfcd1608f3a9 (\"mm/page_alloc: let page freeing clear any set page type\")\nthis leads to the following warning when freeing these pages due to\npage-\u003epage_type sharing page-\u003e_mapcount:\n\n  BUG: Bad page state in process ... pfn:284fbb\n  page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x284fbb\n  flags: 0x17fffc000000000(node=0|zone=2|lastcpupid=0x1ffff)\n  page_type: f2(table)\n  page dumped because: nonzero mapcount\n  Call trace:\n   bad_page+0x13c/0x160\n   __free_frozen_pages+0x6cc/0x860\n   ___free_pages+0xf4/0x180\n   free_pages+0x54/0x80\n   free_hotplug_page_range.part.0+0x58/0x90\n   free_empty_tables+0x438/0x500\n   __remove_pgd_mapping.constprop.0+0x60/0xa8\n   arch_remove_memory+0x48/0x80\n   try_remove_memory+0x158/0x1d8\n   offline_and_remove_memory+0x138/0x180\n\nIt can also lead to leaking the ptl allocation if ALLOC_SPLIT_PTLOCKS is\ndefined and incorrect NR_PAGETABLE stats.  Fix this by calling\npagetable_dtor() in free_hotplug_pgtable_page() prior to freeing the page\nto undo the effects of calling pagetable_*_ctor().","modified":"2026-07-08T08:13:46.289767428Z","published":"2026-07-01T13:32:23.449Z","database_specific":{"cna_assigner":"Linux","osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/53xxx/CVE-2026-53342.json"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/95f27fcda681021ed3906d3cae7e68b6a57a1d8e"},{"type":"WEB","url":"https://git.kernel.org/stable/c/aaa688ac9f18207f7452c6472e647c1febaea6a3"},{"type":"WEB","url":"https://git.kernel.org/stable/c/c594b83457ccdee76d458416fb3bc9348a37592f"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/53xxx/CVE-2026-53342.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-53342"},{"type":"PACKAGE","url":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"5e8eb9aeeda3a7aaf48efa1d34ae804e894e307f"},{"fixed":"95f27fcda681021ed3906d3cae7e68b6a57a1d8e"},{"fixed":"aaa688ac9f18207f7452c6472e647c1febaea6a3"},{"fixed":"c594b83457ccdee76d458416fb3bc9348a37592f"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-53342.json"}},{"package":{"name":"Kernel","ecosystem":"Linux"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"6.16.0"},{"fixed":"6.18.36"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.19.0"},{"fixed":"7.0.13"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-53342.json"}}],"schema_version":"1.7.5"}