In the Linux kernel, the following vulnerability has been resolved:

mm/huge_memory: update file PMD counter before folio_put()

__split_huge_pmd_locked() updates the file/shmem RSS counter after
dropping the PMD mapping's folio reference. If folio_put() drops the last
reference, mm_counter_file() can later read freed folio state via
folio_test_swapbacked().

Move the counter update before folio_put().