I lived in Leodis last year, the area is pretty rough but that's the side opposite to the direction you'll be walking. It is still a bit of a rougher area than maybe some other halls but the walk is quick to uni and there are usually loads of students about. You just try to go out in groups when it's dark and that's about it.
You don't need to worry about safety in the actual halls' grounds because it's gated and you can only get in to the grounds with a fob. Then you need a fob to get into your block, flat and room. Plus there's 24 hour security with a mobile number for you to text (this is usually for noise complaints but can be used for anything else).