Fix sanitize feed description (#3222)

* Fix sanitize feed description

#fix https://github.com/FreshRSS/FreshRSS/issues/3221

* Simplification

app/Models/FeedDAO.php

@@ -62,7 +62,7 @@ class FreshRSS_FeedDAO extends Minz_ModelPdo implements FreshRSS_Searchable {
 			$valuesTmp['category'],
 			mb_strcut(trim($valuesTmp['name']), 0, FreshRSS_DatabaseDAO::LENGTH_INDEX_UNICODE, 'UTF-8'),
 			substr($valuesTmp['website'], 0, 255),
-			mb_strcut($valuesTmp['description'], 0, 1023, 'UTF-8'),
+			sanitizeHTML($valuesTmp['description'], '', 1023),
 			$valuesTmp['lastUpdate'],
 			isset($valuesTmp['priority']) ? intval($valuesTmp['priority']) : FreshRSS_Feed::PRIORITY_MAIN_STREAM,
 			mb_strcut($valuesTmp['pathEntries'], 0, 511, 'UTF-8'),

app/views/helpers/feed/update.phtml

@@ -7,7 +7,7 @@
 		<a href="<?= _url('stats', 'repartition', 'id', $this->feed->id()) ?>"><?= _i('stats') ?> <?= _t('sub.feed.stats') ?></a>
 	</div>
 
-	<p><?= $this->feed->description() ?></p>
+	<p><?= sanitizeHTML($this->feed->description()) ?></p>
 
 	<?php $nbEntries = $this->feed->nbEntries(); ?>
 

lib/lib_rss.php

@@ -241,16 +241,25 @@ function customSimplePie($attributes = array()) {
 	return $simplePie;
 }
 
-function sanitizeHTML($data, $base = '') {
-	if (!is_string($data)) {
+function sanitizeHTML($data, $base = '', $maxLength = false) {
+	if (!is_string($data) || ($maxLength !== false && $maxLength <= 0)) {
 		return '';
 	}
+	if ($maxLength !== false) {
+		$data = mb_strcut($data, 0, $maxLength, 'UTF-8');
+	}
 	static $simplePie = null;
 	if ($simplePie == null) {
 		$simplePie = customSimplePie();
 		$simplePie->init();
 	}
-	return html_only_entity_decode($simplePie->sanitize->sanitize($data, SIMPLEPIE_CONSTRUCT_HTML, $base));
+	$result = html_only_entity_decode($simplePie->sanitize->sanitize($data, SIMPLEPIE_CONSTRUCT_HTML, $base));
+	if ($maxLength !== false && strlen($result) > $maxLength) {
+		//Sanitizing has made the result too long so try again shorter
+		$data = mb_strcut($result, 0, (2 * $maxLength) - strlen($result) - 2, 'UTF-8');
+		return sanitizeHTML($data, $base, $maxLength);
+	}
+	return $result;
 }
 
 /**