CVE-2026-23147

A memory leak flaw was found in the Linux kernel's btrfs filesystem zlib compression code when using S390 hardware acceleration. Due to a missing folio_put() call in the copy_data_into_buffer() function, page cache folios are not released after use during compression operations. This can lead to gradual memory exhaustion on affected S390 systems using btrfs with compression enabled.

This vulnerability is specific to S390 architecture systems using btrfs with zlib compression and hardware acceleration enabled. The flaw was introduced by a code refactor and requires sustained filesystem compression activity to cause noticeable memory pressure.

The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.