MooseFS 4.58.3: Maintenance Release

December 17th, 2025 | MooseFS Team

MooseFS 4.58.3 is a maintenance release aimed at improving stability, correctness, and security. It introduces no new features, but includes several important fixes identified by the community and during internal testing.

Stricter Storage Class Validation

Validation of reversible storage class options has been improved. Previously, the R flag could be accepted on its own, even though it is only meaningful when combined with other modes. The updated logic now rejects invalid combinations, helping prevent configuration mistakes.

Safer Privilege Handling in Daemons

MooseFS daemons now clear all auxiliary groups before dropping privileges from root to a less-privileged user. This small change improves the safety of privilege transitions and aligns the daemons more closely with established security best practices.

libmfsio Stability Fix

A rare bug in the descriptor resize logic within libmfsio has been fixed. While uncommon, resolving this issue improves correctness and robustness in edge-case scenarios.

Overall, 4.58.3 is a low-noise but worthwhile update, particularly for production environments.

We would like to thank the MooseFS Community for reporting issues, sharing feedback, and helping improve the quality and reliability of each release.