Challenge 43 RevengE

You must upload webshell and cat /flag

<html>
<head>
<title>Challenge 43 RevengE</title>
</head>
<body>
<hr>
You must upload webshell and cat <b>/flag</b>
<hr>
<?php
  if(isset($_FILES['file'])){
    $type = $_FILES['file']['type'];
    $name = $_FILES['file']['name'];
    if(!$type) { exit("type not detected"); }
    if(preg_match("/\.\.|\/|\\\|\.htaccess/",$name)) exit("dont do that");
    if(preg_match("/text\/|application\/octet-stream/i",$type)) exit("wrong type");
    $image = new Imagick();
    $image->readImage($_FILES['file']['tmp_name']);
    $image->resizeImage(500, 500, imagick::FILTER_GAUSSIAN, 10);
    $image->writeImage("./upload/".$name);
    echo "Done!<br><br><a href=./upload/{$name}>./upload/{$name}</a>";
  }
?>
<form method=post enctype="multipart/form-data" action=index.php>
<input name=file type=file><input type=submit>
</form>
<hr><?php highlight_file(__FILE__); ?>
</body>
</html>