RW/RX remap test

main.m

#include <mach/mach.h>

void remap(vm_address_t orig, vm_size_t size, bool execute)
{
  // remap source to target
  vm_address_t target = 0;
  uint64_t mask = 0;
  bool anywhere = true;
  vm_address_t source = orig;
  vm_prot_t cur_protection = 0;
  vm_prot_t max_protection = 0;

  kern_return_t retval =
      vm_remap(mach_task_self(), &target, size, mask, anywhere, mach_task_self(), source, false,
               &cur_protection, &max_protection, VM_INHERIT_DEFAULT);
  if (retval != KERN_SUCCESS)
  {
    NSLog(@"remap fail: 0x%x", retval);
    return;
  }
  
  if (execute)
  {
    retval = vm_protect(mach_task_self(), target, size, false, VM_PROT_READ | VM_PROT_EXECUTE);
  }
  else
  {
    retval = vm_protect(mach_task_self(), target, size, false, VM_PROT_READ | VM_PROT_WRITE);
  }
  
  if (retval != KERN_SUCCESS)
  {
    NSLog(@"prot fail: 0x%x", retval);
    return;
  }
  
  NSLog(@"OK, remap at 0x%lx", target);
}

int main(int argc, char* argv[])
{
  vm_size_t vm_size = 4096 * 4;
  vm_address_t vm_mem;
  
  kern_return_t retval = vm_allocate(mach_task_self(), &vm_mem, vm_size, VM_FLAGS_ANYWHERE);
  if (retval != KERN_SUCCESS)
  {
    NSLog(@"vm_allocate: 0x%x", retval);
    return -1;
  }
  
  NSLog(@"vm_mem 0x%lx", vm_mem);
  
  remap(vm_mem, vm_size, false);
  remap(vm_mem, vm_size, true);
  
  return 0;
}