A method includes loading each section of an executable program code into a respective page of memory, configuring permissions for a first page including a first section of the executable program code to enable execution of the first section loaded into the first page. The first section associated with a first label. The method also includes configuring permissions for a second page of the memory including a second section of the executable program code to disable execution of the second section loaded into the second page. The second section associated with a second label. Responsive to a determination that a transition from the first section to the second section is allowed during execution of the executable program code, the method also includes changing the permissions of the second page to enable execution of the second section of the executable program code.