session_destroy() is not logging me out - php

Question

Whenever I run the logout.php script then go back to a page that is protected without login it will have me still logged in
logout.php
<?php
session_start();
session_unset();
session_destroy();
header("Location: ../index.php");
exit();
?>
login.php
$userlogin = user_login($email, $password.$salt);
if ($userlogin==false){
$errors[]='Wrong email/password combination.';
} else {
//set the user session
$_SESSION['UserId']=$userlogin;
$_SESSION['LoginIP']=$_SERVER['REMOTE_ADDR'];
$db->query("UPDATE users SET ipadd='".$_SERVER['REMOTE_ADDR']."' WHERE user_id=".$_SESSION['UserId']."");
echo '<meta http-equiv="refresh" content="0; URL=index.php">';
Check logged in snippet
/* Check if user is logged in or not */
function loggedin(){
return (isset($_SESSION['UserId'])) ? true : false;
}
if (loggedin()==true){
$session_user_id = $_SESSION['UserId'];
$user_data = user_data($session_user_id,'full_name','username');
$rezult =$db->query("SELECT ipadd FROM users WHERE user_id=".$_SESSION['UserId']."");
while($rez = $rezult->fetch_assoc()){
if ($rez['ipadd']==$_SERVER['REMOTE_ADDR']) {
} else {
echo '<meta http-equiv="refresh" content="0; URL=logout2.php">';
}
}
}
Been look at posts with the same question but whatever I try still getting the same issue. Any advice would be extremely appreciated!

Answer 1

this is from php.net http://php.net/manual/en/function.session-destroy.php
Note: You do not have to call session_destroy() from usual code. Cleanup $_SESSION array rather than destroying session data.
so you just need $_SESSION = null, and logout should happen.

Answer 2

I think in your index.php file should have these line:
if(!isset($_SESSION["session_name"])){
header("Location: somewhere_mainpage.php");
}
It is better to make all pages have these line. These line will send header to another page if no session has started.

Answer 3

I believe that session_start(); function call should be on your login page when the user login data is correct, and in your logout PHP code, you should set
session_destroy(); or unset($_SESSION['UserId'];
Logout.php:
<?php
session_destroy();
/* * OR * */
//unset($_SESSION['UserId'];
header("Location: ../index.php");
exit();
?>

Answer 4

<?php
session_unset();
session_destroy();
header("Location: ../index.php");
?>
should work, otherwise you could unset the values
<?php
unset($_SESSION['UserId']); // Unsets the UserId Variable reuse for each variable
session_destroy();
header("Location: ../index.php");
?>
have you tried just session_destroy() ?
also I'm not sure wether you need session_start() when you are closing the session, from memory you only need it to start the session

Answer 5

I always like to destroy the server session, and client cookie, try to manually cover all options in case of any errors.
You can destroy the cookie in PHP with:
setcookie(session_name(), '', time() - 3600, $cookie_path, $cookie_domain, $cookie_secure, $cookie_httponly );
<?php
$cookie_path = "...";
$cookie_domain = "...";
$cookie_secure = "...";
$cookie_httponly = "...";
session_start();
session_unset();
session_destroy();
setcookie(session_name(), '', time() - 3600, $cookie_path, $cookie_domain,$cookie_secure, $cookie_httponly );
header("Location: ../index.php");
exit();
time() - 3600 makes the cookie expiry before the current time, which makes it invalid.
Another option to investigate is session_regenerate_id() on your logout pages. Some reference pages are below:
php.net - session-regenerate-id
https://stackoverflow.com/a/22965580/1246494