Make sure we don't waste entropy
diff --git a/system/core/Security.php b/system/core/Security.php
index 4b204ad..b97df46 100755
--- a/system/core/Security.php
+++ b/system/core/Security.php
@@ -573,6 +573,7 @@
 
 		if (is_readable('/dev/urandom') && ($fp = fopen('/dev/urandom', 'rb')) !== FALSE)
 		{
+			stream_set_chunk_size($fp, $length);
 			$output = fread($fp, $length);
 			fclose($fp);
 			if ($output !== FALSE)