Why stop him....maybe they taste good.

Spray his paws with Bitter Apple :D!

My dog likes to lick both of his front paws and rub his snout on the nails. I want to say it was ever since his paws became a little raw from a really long walk. Now it seems more out of habit because he's been doing it for over 8 months. It's safe for me to correct him in this scenario, but yours is a bit different.

I would investigate where exactly he's licking (bottom, between a particular set of toes, all over). If it's a focused area do you best to look for something that's causing such as a splinter or wound. Get your dog comfortable and in a submissive temperament and gently massage the paw to see if he responds to specific spot. You can also blot his paw with a paper towel to see if any blood or pus shows up.

It's worth giving him a bath and spending extra time cleaning that one paw. The goal is to remove any foreign object causing irritation. And after the bath correct him if he starts back up again with licking.