In a small saucepan, combine cornstarch, cinnamon, and salt. Stir in orange juice and cranberry sauce. Cook over medium heat, stirring, until thickened, and set aside.
Place pork in a shallow roasting pan and cover with about half the cranberry mixture. Insert a meat thermometer. Roast 1 to 1 1/2 hours, basting occasionally with the remaining sauce. Meat is done when thermometer reads 160 degrees F. Remove meat from oven and allow to rest 10 minutes before carving.