Linux is not in the public domain. Linux is a cancer that attaches itself in an intellectual property sense to everything it touches. That's the way that the license works.
Bio: Julia Spencer-Fleming is an American novelist of Mystery fiction. She has won the Agatha Award, Anthony Award, Macavity Awards, Dilys Award, Barry Award, the Nero Award, and Gumshoe Awards. She has also been a finalist for the Edgar Award.