  This paper considers data secrecy in distributed storage systems (DSSs) using
maximally recoverable locally repairable codes (MR-LRCs). Conventional MR-LRCs
are in general not secure against eavesdroppers who can observe the transmitted
data during a global repair operation. This work enables nonzero secrecy
dimension of DSSs encoded by MR-LRCs through a new repair framework. The key
idea is to associate each local group with a central processing unit (CPU),
which aggregates and transmits the contribution from the intact nodes of their
group to the CPU of a group needing a global repair. The aggregation is enabled
by so-called local polynomials that can be generated independently in each
group. Two different schemes -- direct repair and forwarded repair -- are
considered, and their secrecy dimension using MR-LRCs is derived. Positive
secrecy dimension is enabled for several parameter regimes.
