We present an efficient strongly linearizable implementation of the load-linked/store-conditional (LL/SC) primitive from compare-and-swap (CAS) objects. Our algorithm has constant step complexity, and uses a bounded number of CAS objects and registers that can each store O(log n) bits, where n is the number of processes. All previously known wait-free LL/SC algorithms are either not strongly linearizable, or they use objects of unbounded size.