CVE-2025-71295

Summary

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.

Affected Software

VendorProductVersion RangeStatus
LinuxLinuxd0eafc763135508be118dac208887a26c0adb74d < 1b111a69a6e33a922622bf9870e4e63fb2b649c8affected
LinuxLinuxb4fa966f03b7401ceacd4ffd7227197afb2b8376 < c1b6227555c52781178132b7a06466711855795caffected
LinuxLinuxb4fa966f03b7401ceacd4ffd7227197afb2b8376 < 727e5140e0cf83b4ce6a11b89bb73bff5d96f8f3affected
LinuxLinuxb4fa966f03b7401ceacd4ffd7227197afb2b8376 < 42c32d7571ccd8ef32351cac506f00b0fae99fd2affected
LinuxLinuxb4fa966f03b7401ceacd4ffd7227197afb2b8376 < c6246ca15999053d2632fbcc7b86e6eef7f077cbaffected
LinuxLinuxb4fa966f03b7401ceacd4ffd7227197afb2b8376 < b68f91ef3b3fe82ad78c417de71b675699a8467caffected
LinuxLinux6.1.72 < 6.1.165affected
LinuxLinux6.6affected
LinuxLinux0 < 6.6unaffected
LinuxLinux6.1.165 <= 6.1.*unaffected
LinuxLinux6.6.128 <= 6.6.*unaffected
LinuxLinux6.12.75 <= 6.12.*unaffected
LinuxLinux6.18.16 <= 6.18.*unaffected
LinuxLinux6.19.6 <= 6.19.*unaffected
LinuxLinux7.0 <= *unaffected

Weaknesses

References