bug #20146 [Validator] Prevent infinite loop in PropertyMetadata (wes…

…leylancel)

This PR was submitted for the master branch but it was merged into the 2.7 branch instead (closes #20146).

Discussion
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[Validator] Prevent infinite loop in PropertyMetadata

| Q             | A
| ------------- | ---
| Branch?       | 3.1
| Bug fix?      | yes
| New feature?  | no
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets |n/a
| License       | MIT
| Doc PR        | n/a

This commit fixes a possible infinite loop in PropertyMetadata when the PropertyMetadata class was constructed with an existing property of class and later used (after being serialized and cached) on that same class while that property no longer existing. `get_parent_class` will return false when there is no parent class and `property_existing` will then keeping return false causing the `while` loop to be infinite.

Commits
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c1ae7b6 Prevent infinite loop in PropertyMetadata

src/Symfony/Component/Validator/Mapping/PropertyMetadata.php

@@ -58,8 +58,14 @@ public function getPropertyValue($object)
      */
     protected function newReflectionMember($objectOrClassName)
     {
+        $originalClass = is_string($objectOrClassName) ? $objectOrClassName : get_class($objectOrClassName);
+
         while (!property_exists($objectOrClassName, $this->getName())) {
             $objectOrClassName = get_parent_class($objectOrClassName);
+
+            if (false === $objectOrClassName) {
+                throw new ValidatorException(sprintf('Property "%s" does not exist in class "%s"', $this->getName(), $originalClass));
+            }
         }
 
         $member = new \ReflectionProperty($objectOrClassName, $this->getName());

src/Symfony/Component/Validator/Tests/Mapping/PropertyMetadataTest.php

@@ -42,4 +42,14 @@ public function testGetPropertyValueFromOverriddenPrivateProperty()
         $this->assertTrue($metadata->isPublic($entity));
         $this->assertEquals('Overridden data', $metadata->getPropertyValue($entity));
     }
+
+    public function testGetPropertyValueFromRemovedProperty()
+    {
+        $entity = new Entity('foobar');
+        $metadata = new PropertyMetadata(self::CLASSNAME, 'internal');
+        $metadata->name = 'test';
+
+        $this->setExpectedException('Symfony\Component\Validator\Exception\ValidatorException');
+        $metadata->getPropertyValue($entity);
+    }
 }