PHP - empty $_POST and $_FILES - when uploading larger files

Question

I have a following problem, I have HTML form that uploads a file with some extra information. But it allows to upload files that only less then 10MB. But when user tries to

Answer 1

As noted in the edited question $_POST and $_FILES are empty when PHP silently discards data (happens when the actual data is bigger than post_max_size). Since HTTP header and $_GET remain intact those can be used to detect the discards.

Option a)

if(intval($_SERVER['CONTENT_LENGTH'])>0 && count($_POST)===0){
    throw new Exception('PHP discarded POST data because of request exceeding post_max_size.');
}

Option b)
Add a GET parameter that tells whether POST data is present.

Answer 2

i can mention that if you process form like below

if(isset($_POST['submit'])

if post_max_size is lower than posted data then the $_POST['submit'] will be empty

Answer 3

Run phpinfo() and check to make sure your upload_max_filesize and post_max_size directives are large enough.

http://us.php.net/manual/en/ini.core.php#ini.upload-max-filesize

http://us.php.net/manual/en/ini.core.php#ini.post-max-size

Answer 4

You can check for upload errors with:

if ($_FILES['images']['error'] !== UPLOAD_ERR_OK) {
   die("Upload failed with error code " . $_FILES['images']['error']);
}

The error codes are defined here.

Answer 5

There are some limits - both on client and server side.

On client side, the MAX_FILE_SIZE field is not of much use, perhaps browser may take it as a hint; but rather browsers follow their configured limits.

On server side, check php.ini for:

upload_max_filesize = 5M

post_max_size = 5M 

max_input_time = ...

Also check Apache's log for notes about dropped POST body or such.