Methods and systems for substantially simultaneous evaluation of rock sample permeability and porosity, and composition of formation fluids, are provided. Such methods and systems may be used to evaluate the permeability, porosity, and composition of at least a portion of a subterranean formation in a drilling operation. An example of such a method may include passing a cleaning fluid through the rock sample so as to extract at least a portion of one or more formation fluids from the rock sample in an effluent comprising the cleaning fluid and the portion of the one or more formation fluids; and determining one or more properties of the effluent so as to determine the composition of the portion of the one or more formation fluids, and so as to determine the permeability and porosity of the rock sample.