I don't think he needs it fixed. He's not in pain, and he fought a noble fight against the worst monsters in our world. His scars are proof he's the strongest of his siblings, not the runt like others said. He's like Jon.
[Arya]
Ghost won't hurt anyone who doesn't try to hurt us. He was with one of us the longest, Ser Davos said Ghost didn't leave Jon's side when he was dead.