From f8009347c438bef22ef0603ab3d3ccb44bb10bed Mon Sep 17 00:00:00 2001
From: Fabien Potencier <fabien@potencier.org>
Date: Wed, 13 Jul 2022 14:52:38 +0200
Subject: [PATCH] Fix a security issue on filesystem loader (possibility to
 load a template outside a configured directory)

---
 src/Loader/FilesystemLoader.php | 4 ++--
 tests/Loader/FilesystemTest.php | 5 +++++
 2 files changed, 7 insertions(+), 2 deletions(-)

diff --git a/src/Loader/FilesystemLoader.php b/src/Loader/FilesystemLoader.php
index 1912e05a1..7bcdae475 100644
--- a/src/Loader/FilesystemLoader.php
+++ b/src/Loader/FilesystemLoader.php
@@ -221,9 +221,9 @@ protected function findTemplate($name)
         }
 
         try {
-            $this->validateName($name);
-
             list($namespace, $shortname) = $this->parseName($name);
+
+            $this->validateName($shortname);
         } catch (LoaderError $e) {
             if (!$throw) {
                 return false;
diff --git a/tests/Loader/FilesystemTest.php b/tests/Loader/FilesystemTest.php
index 3307a9b7e..eb6ec7e16 100644
--- a/tests/Loader/FilesystemTest.php
+++ b/tests/Loader/FilesystemTest.php
@@ -31,6 +31,7 @@ public function testGetSourceContext()
     public function testSecurity($template)
     {
         $loader = new FilesystemLoader([__DIR__.'/../Fixtures']);
+        $loader->addPath(__DIR__.'/../Fixtures', 'foo');
 
         try {
             $loader->getCacheKey($template);
@@ -62,6 +63,10 @@ public function getSecurityTests()
             ['filters\\\\..\\\\..\\\\AutoloaderTest.php'],
             ['filters\\//../\\/\\..\\AutoloaderTest.php'],
             ['/../AutoloaderTest.php'],
+            ['@__main__/../AutoloaderTest.php'],
+            ['@foo/../AutoloaderTest.php'],
+            ['@__main__/../../AutoloaderTest.php'],
+            ['@foo/../../AutoloaderTest.php'],
         ];
     }