{"id":"CVE-2026-89836","revision":"d24a3c5f2f1f44c88d5e99b8dc1749c8","records":[{"revision":"d24a3c5f2f1f44c88d5e99b8dc1749c8","observedAt":"2026-10-23T15:48:27.903+00:00","statement":{"source":"cve-program","id":"CVE-2026-89836","aliases":[],"title":"f2fs: fix folio_nr_pages() race after put in large folio invalidate","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nf2fs: fix folio_nr_pages() race after put in large folio invalidate\n\nOur v6.18 based Android system is continuely suffering livelock and bad\npage stat as shown in[1] which related to broken xarray slot status. By\ninvestigating big folio operations within f2fs, we find below races and\nfix it by get the nr_pages before drop the refcount and folio_lock.\n\nf2fs_get_read_data_folio() calls f2fs_folio_put() before\nfolio_nr_pages() when invalidating a large folio from the page cache.\nThat unlocks the folio and drops the caller reference, leaving a window\nwhere a concurrent truncate or folio split can shrink the compound folio\nor free it before the invalidate range is computed. An undersized range\nthen leaves split sub-folios in mapping->i_pages, which can later\ninteract badly with truncate and reclaim (stale xarray entries and bad\npage state when folio->mapping no longer matches the mapping being\ntruncated).\n\n[1]\nPID: 2594     TASK: ffffff8169b81580  CPU: 7    COMMAND: \"Thread-3\"\n #0 [ffffffc08ef2b8a0] xas_load at ffffffe52d1f42a4\n #1 [ffffffc08ef2b900] find_get_entries at ffffffe52c185798\n #2 [ffffffc08ef2bb60] truncate_inode_pages_range at ffffffe52c19e83c\n #3 [ffffffc08ef2bbc0] truncate_inode_pages_final at ffffffe52c19ec2c\n #4 [ffffffc08ef2bc20] f2fs_evict_inode at ffffffe52c4c8400\n #5 [ffffffc08ef2bcc0] evict at ffffffe52c2de9f4\n #6 [ffffffc08ef2bd00] iput at ffffffe52c2db1b4\n #7 [ffffffc08ef2bd30] dentry_unlink_inode at ffffffe52c2d7204\n #8 [ffffffc08ef2bd50] __dentry_kill at ffffffe52c2d3dcc\n #9 [ffffffc08ef2bd80] dput at ffffffe52c2d3c3c\n #10 [ffffffc08ef2bda0] __fput at ffffffe52c2b0a7c\n #11 [ffffffc08ef2bde0] ____fput at ffffffe52c2b1034\n #12 [ffffffc08ef2bdf0] task_work_run at ffffffe52beea200\n #13 [ffffffc08ef2be20] exit_to_user_mode_loop at ffffffe52bfbc17c\n #14 [ffffffc08ef2be80] el0_svc at ffffffe52d1f8e54\n #15 [ffffffc08ef2beb0] el0t_64_sync_handler at ffffffe52d1f8d10","state":0,"publishedAt":"2026-09-16T10:31:10.233+00:00","modifiedAt":"2026-10-19T08:53:29.553+00:00","affected":[{"ecosystem":"Vendor product","name":"Linux","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"product\": \"Linux\",\n                    \"vendor\": \"Linux\",\n                    \"defaultStatus\": \"unaffected\",\n                    \"repo\": \"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\n                    \"programFiles\": [\n                        \"fs/f2fs/data.c\"\n                    ],\n                    \"versions\": [\n                        {\n                            \"version\": \"05e65c14ea59a401cec4284e9d612f9d5dc1b3f8\",\n                            \"lessThan\": \"cc34df18da92f68f9b384c3ae95ad64be46cb5ee\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"05e65c14ea59a401cec4284e9d612f9d5dc1b3f8\",\n                            \"lessThan\": \"0dab71381f1b4d12dc2056f8bd5aaa9d93ce9082\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        }\n                    ]\n                }"},{"ecosystem":"Vendor product","name":"Linux","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"product\": \"Linux\",\n                    \"vendor\": \"Linux\",\n                    \"defaultStatus\": \"affected\",\n                    \"repo\": \"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\n                    \"programFiles\": [\n                        \"fs/f2fs/data.c\"\n                    ],\n                    \"versions\": [\n                        {\n                            \"version\": \"7.0\",\n                            \"status\": \"affected\"\n                        },\n                        {\n                            \"version\": \"0\",\n                            \"lessThan\": \"7.0\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"7.2.5\",\n                            \"lessThanOrEqual\": \"7.2.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"7.3\",\n                            \"lessThanOrEqual\": \"*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"original_commit_for_fix\"\n                        }\n                    ]\n                }"}],"metrics":[{"system":"CVSS 3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","score":7.8,"severity":"HIGH"}],"references":["https://git.kernel.org/stable/c/cc34df18da92f68f9b384c3ae95ad64be46cb5ee","https://git.kernel.org/stable/c/0dab71381f1b4d12dc2056f8bd5aaa9d93ce9082"],"sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-89836","license":"CVE Program Terms of Use","key":"cve-program:CVE-2026-89836","identifiers":["CVE-2026-89836"]},"retained":false,"historicalAffected":[]}],"coverage":[]}