Fix #3666: Properly catch out-of-bounds image reads (based on patch b…

…y Rubidium)
OpenTTD · Feb 11, 2012 · c2db67b · c2db67b
1 parent b2f1327
commit c2db67b
Showing 1 changed file with 3 additions and 0 deletions.
diff --git a/nml/output_grf.py b/nml/output_grf.py
@@ -119,6 +119,9 @@ def print_sprite(self, sprite_info):
         y = sprite_info.ypos.value
         size_x = sprite_info.xsize.value
         size_y = sprite_info.ysize.value
+        (im_width, im_height) = im.size
+        if x + size_x > im_width or y + size_y > im_height:
+            raise generic.ScriptError("Read beyond bounds of image file '%s'" % sprite_info.file.value, sprite_info.file.pos)
         sprite = im.crop((x, y, x + size_x, y + size_y))
 
         # Check for white pixels; those that cause "artefacts" when shading