使用PTRACE_POKEDATA替换进程堆中的数据

Question

我想使用ptrace将我的工具附加到Linux进程，读取和写入此进程的堆内存并再次分离我的工具。 实际上，虽然没有错误，但它不起作用。运行该工具后，我无法在进程的堆内存中看到任何修改。无论如何，我不太确定这是否可能。目前，我的C代码如下所示：

      int res = 0, i = 0;
      int size = heap_address->end - heap_address->start;

      char tmp_page[size];
      memset(tmp_page, 'x', size); // just a test, I know this makes no sense

      printf(" -> Attaching to process...\n");
      res = ptrace(PTRACE_ATTACH, pid, NULL, NULL);
      if (res == -1) printf(" -> Error: ptrace attach\n");
      res = waitpid(pid, NULL, WUNTRACED);
      if (res != pid) printf(" -> Error: waitpid\n");

      printf(" -> Replacing heap\n");
      for (i=0; i < size; i+=4) {
       res = ptrace(PTRACE_POKEDATA, pid, heap_address->start+i, *(int *)(tmp_page+i));
         if (res == -1) printf(" -> Error: ptrace pokedata\n");
      }

      printf(" -> Detaching from process...\n");
      res = ptrace(PTRACE_DETACH, pid, NULL, NULL);
      if (res == -1) printf(" -> Error: ptrace detach\n");