Gilgit baltistan is nearly half the size of bangladesh and greater then sri lanka with a very complex topography. just as for russia only local inhabitants know how to use their land against massive invasions , similarily the local inhabitants are well aware of fighting in GB's complex terrain and then we have our best military assets deployed there. It took months for indian army to retake kargil and then the winter limitations itself is a great threat for any invading force , so practically any indian invasion in gilgit baltistan is bound to be proven a major disaster for any invading force. They most probably will try something else then going direct after gilgit baltistan.