The present application relates to a direct memory access, DMA, controller for a data processing system and a method of operating the DMA controller is provided. The DMA controller comprises a transfer table, a data path processing block and a comparator logic block. The table comprises at least one transfer descriptor comprising information about a source and destination of a DMA transfer. The data path processing block is provided to be coupled to a system interconnect of the data processing system and configured to receive data from the source of the DMA transfer and to transfer the received data to the destination of the DMA transfer. The comparator logic block is configured to validate the value of the received data against a predefined value range for range checking and to initiate one or more failed range check actions in response to a failed range checking.