That was Summer and Shaddydog
Summer (light Grey almost White)
http://images1.wikia.nocookie.net/__cb20130318145913/gameofthrones/images/8/87/SummerS3.jpg
Shaddydog (very very dark brown/black, he is the one on the left)
http://images4.wikia.nocookie.net/__cb20120604073444/gameofthrones/images/thumb/8/8e/Bran%2C_Hodor%2C_Summer_and_Shaggydog.jpg/640px-Bran%2C_Hodor%2C_Summer_and_Shaggydog.jpg
Ghost (pure white)
http://images3.wikia.nocookie.net/cb20110625085821/gameofthrones/images/a/ab/Ghost.png
http://images3.wikia.nocookie.net/cb20110302121354/gameofthrones/images/thumb/4/4d/Ghost.jpg/300px-Ghost.jpg
Edit: Just to remind you that Ghost is not with Jon when he is with the wildlings. In the show they never show it but Jon gives Ghost instructions to return to Castle Black, though Jon is not sure if Ghost understands. In the show it is not commented on but Ghost is on the wrong side of the magic wall, ghost is above the wall instead below it inside the gift.