[BUGFIX] Prevent TypeError in FileSearchDemand

Since `QueryHelper::parseOrderBy()` might return
NULL as value for fieldname and direction, we
now check those values properly to prevent any
TypeErrors using the type-hinted `addOrdering()`
method.

Resolves: #102649
Releases: main, 12.4
Change-Id: Ie117e7fd0593392e843aaca5c1e9c254c4de42d1
Reviewed-on: https://review.typo3.org/c/Packages/TYPO3.CMS/+/82168


Tested-by: Oliver Bartsch <bo@cedev.de>
Tested-by: Christian Kuhn <lolli@schwarzbu.ch>
Reviewed-by: Oliver Bartsch <bo@cedev.de>
Tested-by: core-ci <typo3@b13.com>
Reviewed-by: Christian Kuhn <lolli@schwarzbu.ch>
Reviewed-by: Oliver Klee <typo3-coding@oliverklee.de>
Tested-by: Garvin Hicking <gh@faktor-e.de>
Reviewed-by: Garvin Hicking <gh@faktor-e.de>
Tested-by: Stefan Bürk <stefan@buerk.tech>
Reviewed-by: Stefan Bürk <stefan@buerk.tech>
Reviewed-by: Thomas Hohn <tho@gyldendal.dk>

typo3/sysext/core/Classes/Resource/Search/FileSearchQuery.php

@@ -94,7 +94,10 @@ class FileSearchQuery
         if ($searchDemand->getOrderings() === null) {
             $orderBy = ($GLOBALS['TCA'][self::FILES_TABLE]['ctrl']['sortby'] ?? '') ?: ($GLOBALS['TCA'][self::FILES_TABLE]['ctrl']['default_sortby'] ?? '');
             foreach (QueryHelper::parseOrderBy((string)$orderBy) as [$fieldName, $order]) {
-                $searchDemand = $searchDemand->addOrdering(self::FILES_TABLE, $fieldName, $order);
+                if (is_string($fieldName) && $fieldName !== '') {
+                    // Call add ordering only for valid field names
+                    $searchDemand = $searchDemand->addOrdering(self::FILES_TABLE, $fieldName, $order ?? 'ASC');
+                }
             }
         }
         foreach ($searchDemand->getOrderings() as [$tableName, $fieldName, $direction]) {