Officially… The answer should be no.
But, if I were on the plane, would be no problem.
All of our bread comes in oven-able plastic bags, so we don't have to worry about that side of it from what is supplied by the caterers, however there is not always things like foil kicking around, so if you can, maybe wrap it in foil incase they don't have any to use.
As I say, the official answer is no, as we are not supposed to heat or cook any passengers own food, but I honestly can not see the harm in a couple of bread rolls.
But be prepared for a no, incase you get one.