Filemanager checks empty array 6.4.13

[dorothyDorothy]

I upgraded an add-on which makes use of system/ee/legacy/libraries/Filemanager.php
The call to fetch_upload_dir_prefs() throws an error because the _upload_dir_prefs array has no elements in it.
This is the error:

TypeError Caught
Illegal offset type in isset or empty

The line to check for the empty array is currently:

if (isset($this->_upload_dir_prefs[$dir_id])) {
      return $this->_upload_dir_prefs[$dir_id];
}

I suggest changing this to:

if ((count($this->_upload_dir_prefs) > 0) && (isset($this->_upload_dir_prefs[$dir_id])) ) {
   return $this->_upload_dir_prefs[$dir_id];
}

So that it checks if there are any elements before it starts checking if a particular element exists. This stops an error being thrown.

See line 156 of system/ee/legacy/libraries/Filemanager.php

How To Reproduce
Using Reinos Single Sign On version v5.4.3

Error Messages

TypeError Caught
Illegal offset type in isset or empty

Screenshots / Videos / Template Code

Environment Details:

• Version: 6.4.13
• PHP Version 8.2
• MySQL Version 8.0.34-0ubuntu0.22.04.1 for Linux on x86_64
• OS: Linux
• Web Server: Apache

Possible Solution
in system/ee/legacy/libraries/Filemanager.php
public function fetch_upload_dir_prefs($dir_id, $ignore_site_id = false)

if ((count($this->_upload_dir_prefs) > 0) && (isset($this->_upload_dir_prefs[$dir_id])) ) {

return $this->_upload_dir_prefs[$dir_id];

}

Additional context

[intoeetive]

@matthewjohns0n this looks like PHP compatibility issue where _upload_dir_prefs is defined as null vs array

[dorothyDorothy]

The array wasn't null but it was zero length.