The glass sheet on the inside of our oven has come away from its metal casing. How do I glue it back?

The door itself has an outside heat proof door and inside has a metal door with hole in it filled with a sheet of glass about 20cm square which allows you to see through into the oven. The glass has come away from the metal casing and needs to be fixed back. I’m pretty sure there aren’t any ordinary glues we can use due to the temperatures involved and was hoping someone can advise me?