For very large posts (~18k) with lots of markup, these regexes were causing enough backtracking for php to run out of memory, silently generating an empty entry. This tightens up the regexes so they do less backtracking.

include/bbcode.php

@@ -642,8 +642,8 @@ function bbcode($Text,$preserve_nl = false, $tryoembed = true, $simplehtml = fal
 	$Text = preg_replace('/\&quot\;/','"',$Text);
 
 	// fix any escaped ampersands that may have been converted into links
-	$Text = preg_replace("/\<(.*?)(src|href)=(.*?)\&amp\;(.*?)\>/ism",'<$1$2=$3&$4>',$Text);
-	$Text = preg_replace("/\<(.*?)(src|href)=\"[^hfm](.*?)\>/ism",'<$1$2="">',$Text);
+	$Text = preg_replace("/\<([^>]*?)(src|href)=(.*?)\&amp\;(.*?)\>/ism",'<$1$2=$3&$4>',$Text);
+	$Text = preg_replace("/\<([^>]*?)(src|href)=\"[^hfm](.*?)\>/ism",'<$1$2="">',$Text);
 
 	if($saved_image)
 		$Text = bb_replace_images($Text, $saved_image);