You can undo that change.
As expected, $CONFIG['allowed_file_extensions'] is empty. As far as I can see it is set in this function:
function cpg_get_type($filename,$filter=null)
{
global $CONFIG;
static $FILE_TYPES = array();
if (!$FILE_TYPES) {
// Map content types to corresponding user parameters
$content_types_to_vars = array(
'image' => 'allowed_img_types',
'audio' => 'allowed_snd_types',
'movie' => 'allowed_mov_types',
'document' => 'allowed_doc_types',
);
$result = cpg_db_query('SELECT extension, mime, content, player FROM ' . $CONFIG['TABLE_FILETYPES']);
$CONFIG['allowed_file_extensions'] = '';
while ( ($row = mysql_fetch_assoc($result)) ) {
// Only add types that are in both the database and user defined parameter
if ($CONFIG[$content_types_to_vars[$row['content']]] == 'ALL' || is_int(strpos('/' . $CONFIG[$content_types_to_vars[$row['content']]] . '/', '/' . $row['extension'] . '/'))) {
$FILE_TYPES[$row['extension']] = $row;
$CONFIG['allowed_file_extensions'] .= '/' . $row['extension'];
}
}
$CONFIG['allowed_file_extensions'] = substr($CONFIG['allowed_file_extensions'], 1);
mysql_free_result($result);
}
if (!is_array($filename)) {
$filename = explode('.', $filename);
}
$EOA = count($filename) - 1;
$filename[$EOA] = strtolower($filename[$EOA]);
if (!is_null($filter) && array_key_exists($filename[$EOA], $FILE_TYPES) && ($FILE_TYPES[$filename[$EOA]]['content'] == $filter)) {
return $FILE_TYPES[$filename[$EOA]];
} elseif (is_null($filter) && array_key_exists($filename[$EOA], $FILE_TYPES)) {
return $FILE_TYPES[$filename[$EOA]];
} else {
return null;
}
}
Are you able to debug this yourself? I never had a deeper look at this function and am currently short of time. But it cannot hurt to output all variables and array of that function.