{"id":"CVE-2026-93239","summary":"arm64: mm: Fix the lockless page-table walk in show_pte()","details":"In the Linux kernel, the following vulnerability has been resolved:\n\narm64: mm: Fix the lockless page-table walk in show_pte()\n\nshow_pte() walks page tables locklessly and can run with interrupts\nenabled. A concurrent teardown can free a table page while it is being\nwalked. It can also clear a parent entry after show_pte() checked it; the\nregular pXd_offset() helpers then reread the cleared entry and can derive a\nbogus lower-level pointer and fault again.\n\nUse the lockless offset helpers with the saved parent entries, as\ngup_fast() does, and pass the saved PMD to pte_offset_map().\n\nFor task page tables, arm64 selects MMU_GATHER_RCU_TABLE_FREE. Disable\nlocal interrupts around the walk to hold off RCU-deferred table frees and\nblock the tlb_remove_table_sync_one() IPI until the walk is finished.\n\nPlace the IRQ guard after the header print. This does not make the output a\nconsistent snapshot, but prevents the task page-table walk from\ndereferencing a released table page or deriving a pointer from a different\nparent value.","modified":"2026-09-25T03:48:54.244306528Z","published":"2026-09-24T15:34:27.219Z","database_specific":{"cna_assigner":"Linux","osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/93xxx/CVE-2026-93239.json"},"references":[{"type":"PACKAGE","url":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"},{"type":"WEB","url":"https://git.kernel.org/stable/c/08d931a0a850ad16a64f2cd23a19f40795cdbdf7"},{"type":"WEB","url":"https://git.kernel.org/stable/c/0f05d95b99164a9ccc4cf4a4920e0ff0228138ad"},{"type":"WEB","url":"https://git.kernel.org/stable/c/68cbd70795dd8c06e7ccdc4eb0b74c5b180076c3"},{"type":"WEB","url":"https://git.kernel.org/stable/c/a77644d009dece1104b6fcc6e322b0e4503db0d6"},{"type":"WEB","url":"https://git.kernel.org/stable/c/b28fe65a36b8209b6adcf2722c7ce974cf9ac8d1"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/93xxx/CVE-2026-93239.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-93239"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"1d18c47c735e8adfe531fc41fae31e98f86b68fe"},{"fixed":"08d931a0a850ad16a64f2cd23a19f40795cdbdf7"},{"fixed":"b28fe65a36b8209b6adcf2722c7ce974cf9ac8d1"},{"fixed":"68cbd70795dd8c06e7ccdc4eb0b74c5b180076c3"},{"fixed":"0f05d95b99164a9ccc4cf4a4920e0ff0228138ad"},{"fixed":"a77644d009dece1104b6fcc6e322b0e4503db0d6"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-93239.json"}},{"package":{"name":"Kernel","ecosystem":"Linux"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"3.7.0"},{"fixed":"6.6.157"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.7.0"},{"fixed":"6.12.110"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.13.0"},{"fixed":"6.18.51"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.19.0"},{"fixed":"7.2.5"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-93239.json"}}],"schema_version":"1.9.0"}