[Security] Throw an explicit error when authenticating a token with a…

… null user

Firewall/ContextListener.php

@@ -123,6 +123,10 @@ public function authenticate(RequestEvent $event): void
         ]);
 
         if ($token instanceof TokenInterface) {
+            if (!$token->getUser()) {
+                throw new \UnexpectedValueException(\sprintf('Cannot authenticate a "%s" token because it doesn\'t store a user.', $token::class));
+            }
+
             $originalToken = $token;
             $token = $this->refreshUser($token);
 

Tests/Firewall/ContextListenerTest.php

@@ -36,6 +36,7 @@
 use Symfony\Component\Security\Core\User\UserInterface;
 use Symfony\Component\Security\Core\User\UserProviderInterface;
 use Symfony\Component\Security\Http\Firewall\ContextListener;
+use Symfony\Component\Security\Http\Tests\Fixtures\NullUserToken;
 use Symfony\Contracts\Service\ServiceLocatorTrait;
 
 class ContextListenerTest extends TestCase
@@ -58,6 +59,30 @@ public function testUserProvidersNeedToImplementAnInterface()
         $this->handleEventWithPreviousSession([new \stdClass()]);
     }
 
+    public function testTokenReturnsNullUser()
+    {
+        $tokenStorage = new TokenStorage();
+        $tokenStorage->setToken(new NullUserToken());
+
+        $session = new Session(new MockArraySessionStorage());
+        $session->set('_security_context_key', serialize($tokenStorage->getToken()));
+
+        $request = new Request();
+        $request->setSession($session);
+        $request->cookies->set('MOCKSESSID', true);
+
+        $listener = new ContextListener($tokenStorage, [], 'context_key');
+
+        $this->expectException(\UnexpectedValueException::class);
+        $this->expectExceptionMessage('Cannot authenticate a "Symfony\Component\Security\Http\Tests\Fixtures\NullUserToken" token because it doesn\'t store a user.');
+
+        $listener->authenticate(new RequestEvent(
+            $this->createMock(HttpKernelInterface::class),
+            $request,
+            HttpKernelInterface::MAIN_REQUEST,
+        ));
+    }
+
     public function testOnKernelResponseWillAddSession()
     {
         $session = $this->runSessionOnKernelResponse(

Tests/Fixtures/NullUserToken.php

@@ -0,0 +1,23 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\Security\Http\Tests\Fixtures;
+
+use Symfony\Component\Security\Core\Authentication\Token\AbstractToken;
+use Symfony\Component\Security\Core\User\UserInterface;
+
+class NullUserToken extends AbstractToken
+{
+    public function getUser(): ?UserInterface
+    {
+        return null;
+    }
+}