CVE-2026-23147

In the Linux kernel, the following vulnerability has been resolved:<br /> <br /> btrfs: zlib: fix the folio leak on S390 hardware acceleration<br /> <br /> [BUG]<br /> After commit aa60fe12b4f4 ("btrfs: zlib: refactor S390x HW acceleration<br /> buffer preparation"), we no longer release the folio of the page cache<br /> of folio returned by btrfs_compress_filemap_get_folio() for S390<br /> hardware acceleration path.<br /> <br /> [CAUSE]<br /> Before that commit, we call kumap_local() and folio_put() after handling<br /> each folio.<br /> <br /> Although the timing is not ideal (it release previous folio at the<br /> beginning of the loop, and rely on some extra cleanup out of the loop),<br /> it at least handles the folio release correctly.<br /> <br /> Meanwhile the refactored code is easier to read, it lacks the call to<br /> release the filemap folio.<br /> <br /> [FIX]<br /> Add the missing folio_put() for copy_data_into_buffer().