  tt_glyphzone_done( TT_GlyphZone  zone )
  {
    FT_Memory  memory = zone->memory;


    if ( memory )
    {
      FT_FREE( zone->contours );
      FT_FREE( zone->tags );
      FT_FREE( zone->cur );
      FT_FREE( zone->org );
      FT_FREE( zone->orus );

      zone->max_points   = zone->n_points   = 0;
      zone->max_contours = zone->n_contours = 0;
      zone->memory       = NULL;
    }
  }

The product writes data past the end, or before the beginning, of the intended buffer.