We see it happen a lot in rap music - producers 'sampling'/stealing a part of another older song hoping nobody will notice. Sampling isn't a bad thing, the only time it becomes a problem is when a producer/artist doesn't get authorisation to use it. It's now Eminem's turn to receive a lawsuit causing him of not crediting and gaining clearance of his 2013 hit "Rap God".
From the sounds of both tracks, it's definitely sounds like that might be a definite sample, we're thinking Slim Shady is going to have to pay up. Not only is the beat the similar, so are the flow and lyrics.