What could happen with upload img script?

[klassasin]

Use the following code (it is a modification of my own code; use it instead of that code):

<?
if(!isset($_FILES['userfile'])) exit;

$maxsize = 100000;
$uploadDir = "upload/";
$fsize = $_FILES['userfile']['size'];
$fmime = $_FILES['userfile']['type'];

$uploadName = $_FILES['userfile']['name'];
$fext = substr($uploadName,strrpos($uploadName,'.')); 
$uploadFile = $uploadDir . $uploadName;

if(($fmime == "image/gif") || ($fmime == "image/jpeg") || ($fmime == "image/pjpeg")) {
  if($fsize < $maxsize) {
    if(strlen($uploadName) < 34) {
      uploadIt();
    } else {
      die("<strong>Filename is over 30 characters.</strong>");
    } 
  } else {
    die("<strong>File is too large.</strong>");
  }
 } else {
    die("<strong>File type is invalid.</strong>");
 }
} else {
    uploadIt();
} 
 
function uploadIt()
{
 global $uploadFile;
 if(move_uploaded_file($_FILES['userfile']['tmp_name'],$uploadFile)) {
   print "<strong>File successfully uploaded</strong><br /><br /><a href=\"$uploadDir\">Upload Directory</a>";
 } else {
   print "Upload <strong>FAILED!</strong><br />";
 }
}
?>