FileCache: rebuild cache file before touch when different file owner (#16120)

* Test Travis envs

* The fix

* posix_geteuid only exists on Linux

* Added PR to changelog

.travis.yml

@@ -32,6 +32,7 @@ env:
     - TASK_TESTS_PHP=1
     - TASK_TESTS_JS=0
     - TASK_TESTS_COVERAGE=0
+    - TRAVIS_SECOND_USER=travis_two
 
 
 services:
@@ -147,6 +148,9 @@ install:
       travis_retry npm install
     fi
 
+  # Needed for FileCacheTest
+  - sudo useradd $TRAVIS_SECOND_USER --gid $(id -g) -M
+
 before_script:
   #
   # Disable:

framework/CHANGELOG.md

@@ -10,6 +10,7 @@ Yii Framework 2 Change Log
 - Bug #15988: Fixed bash completion (alekciy)
 - Bug #15117: Fixed `yii\db\Schema::getTableMetadata` cache refreshing (boboldehampsink)
 - Bug #16073: Fixed regression in Oracle `IN` condition builder for more than 1000 items (cebe)
+- Bug #16120: FileCache: rebuild cache file before touch when different file owner (Slamdunk)
 
 
 2.0.15.1 March 21, 2018

framework/caching/FileCache.php

@@ -141,6 +141,12 @@ class FileCache extends Cache
         if ($this->directoryLevel > 0) {
             @FileHelper::createDirectory(dirname($cacheFile), $this->dirMode, true);
         }
+        // If ownership differs the touch call will fail, so we try to
+        // rebuild the file from scratch by deleting it first
+        // https://github.com/yiisoft/yii2/pull/16120
+        if (is_file($cacheFile) && function_exists('posix_geteuid') && fileowner($cacheFile) !== posix_geteuid()) {
+            @unlink($cacheFile);
+        }
         if (@file_put_contents($cacheFile, $value, LOCK_EX) !== false) {
             if ($this->fileMode !== null) {
                 @chmod($cacheFile, $this->fileMode);

tests/framework/caching/FileCacheTest.php

@@ -52,4 +52,39 @@ class FileCacheTest extends CacheTestCase
         static::$time++;
         $this->assertFalse($cache->get('expire_testa'));
     }
+
+    public function testCacheRenewalOnDifferentOwnership()
+    {
+        $TRAVIS_SECOND_USER = getenv('TRAVIS_SECOND_USER');
+        if (empty($TRAVIS_SECOND_USER)) {
+            $this->markTestSkipped('Travis second user not found');
+        }
+
+        $cache = $this->getCacheInstance();
+
+        $cacheValue = uniqid('value_');
+        $cachePublicKey = uniqid('key_');
+        $cacheInternalKey = $cache->buildKey($cachePublicKey);
+
+        static::$time = \time();
+        $this->assertTrue($cache->set($cachePublicKey, $cacheValue, 2));
+        $this->assertSame($cacheValue, $cache->get($cachePublicKey));
+
+        $refClass = new \ReflectionClass($cache);
+        $refMethodGetCacheFile = $refClass->getMethod('getCacheFile');
+        $refMethodGetCacheFile->setAccessible(true);
+        $cacheFile = $refMethodGetCacheFile->invoke($cache, $cacheInternalKey);
+        $refMethodGetCacheFile->setAccessible(false);
+
+        $output = array();
+        $returnVar = null;
+        exec(sprintf('sudo chown %s %s',
+            escapeshellarg($TRAVIS_SECOND_USER),
+            escapeshellarg($cacheFile)
+        ), $output, $returnVar);
+
+        $this->assertSame(0, $returnVar, 'Cannot change ownership of cache file to test cache renewal');
+
+        $this->assertTrue($cache->set($cachePublicKey, uniqid('value_2_'), 2), 'Cannot rebuild cache on different file ownership');
+    }
 }