From Pokémon X and Y onward, if at least one parent holds a Destiny Knot, the baby will inherit five IVs instead of three.
This can be combined with an EV-enhancing item to ensure that one desired IV is always inherited; however, the offspring will still inherit only a total of five IVs from its parents (the EV-enhancing item simply guarantees which IV will be transferred for one of the five that the Destiny Knot allows).
So no matter how lucky you are, it's impossible for a Pokemon to inherit all six IVs; one IV will always be randomly generated.
Hope I helped. :)