Waking up during surgery is very rare but if you do wake up during surgery it's known as anesthesia awareness.
When you do wake up because of anesthesia awareness you will usually not feel anything or any pain and the doctors that are with you while the surgery is being performed should put you back under while the surgery is being performed.
Th chance of waking up during surgery is very low because the doctors really know what they are doing and will give you the proper amount of anesthesia to keep you from waking up during the surgery.
It's estimated that only 1 in 19,000 surgery patients do wake up during surgery so it's a very low chance that you will wake up during surgery.