CVE-2025-71295

In the Linux kernel, the following vulnerability has been resolved: fs/buffer: add alert in try_to_free_buffers() for folios without buffers try_to_free_buffers() can be called on folios with no buffers attached when filemap_release_folio() is invoked on a folio belonging to a mapping with AS_RELEASE_ALWAYS set but no release_folio operation defined. In such cases, folio_needs_release() returns true because of the AS_RELEASE_ALWAYS flag, but the folio has no private buffer data. This causes try_to_free_buffers() to call drop_buffers() on a folio with no buffers, leading to a null pointer dereference. Adding a check in try_to_free_buffers() to return early if the folio has no buffers attached, with WARN_ON_ONCE() to alert about the misconfiguration. This provides defensive hardening.

• linux linux kernel (>= 6.1.72 < 6.1.165) • linux linux kernel (>= 6.2 < 6.6.128) • linux linux kernel (>= 6.7 < 6.12.75) • linux linux kernel (>= 6.13 < 6.18.16) • linux linux kernel (>= 6.19 < 6.19.6)