The names of Simon Peter and Malchus are mentioned only by John in connection with this incident. The incident itself is related by all the Evangelists.
A sword
Contrary to the rule which forbade the carrying of weapons on a feast-day.
The high priest's servant
See on Mat 26:51.
Right ear
Luke and John. The others do not specify which ear. For ear John and Mark have ὠτάριον, a diminutive; Luke, οὐς, and Matthew, ὠτίον, a diminutive in form, but not in force. See on Mat 26:51.