CVE-2026-53189 mm/huge_memory: update file PMD counter before folio_put()

In the Linux kernel, the following vulnerability has been resolved: mm/hugememory: update file PMD counter before folioput splithugepmdlocked updates the file/shmem RSS counter after dropping the PMD mapping's folio reference. If folioput drops the last reference, mmcounterfile can later read fre...