Fixes #8549: Fixed `yii\caching\FileCache` doesn't lock cache files when reading

framework/CHANGELOG.md

@@ -17,6 +17,7 @@ Yii Framework 2 Change Log
 - Bug #8592: Fixed `yii\db\Command::getRawSql()` unable to parse params specified without colon (':') (klimov-paul)
 - Bug #8593: Fixed `yii\db\ActiveQuery` produces incorrect SQL for aggregations, when `sql` field is set (klimov-paul)
 - Bug #8595: Fixed `yii\rbac\DbManager::checkAccessFromCache()` to check against auth items loaded in cache recursively (achretien, qiangxue)
+- Bug #8549: Fixed `yii\caching\FileCache` doesn't lock cache files when reading (iworker)
 - Bug #8606: Fixed `yii\web\Response::xSendFile()` does not reset format (vyants)
 - Bug #8627: Fixed `yii\db\Migration` produces incorrect results due to table schema caching (klimov-paul)
 - Bug #8661: Fixed `yii.activeForm.js` scrolling to top (nkovacs)
@@ -44,7 +45,6 @@ Yii Framework 2 Change Log
 - Chg #6354: `ErrorHandler::logException()` will now log the whole exception object instead of only its string representation (cebe)
 - Chg #8556: Extracted `yii\web\User::getAuthManager()` method (samdark)
 
-
 2.0.4 May 10, 2015
 ------------------
 

framework/caching/FileCache.php

@@ -107,11 +107,19 @@ class FileCache extends Cache
     protected function getValue($key)
     {
         $cacheFile = $this->getCacheFile($key);
+
         if (@filemtime($cacheFile) > time()) {
-            return @file_get_contents($cacheFile);
-        } else {
-            return false;
+            $fp = @fopen($cacheFile, 'r');
+            if ($fp !== false) {
+                @flock($fp, LOCK_SH);
+                $cacheValue = @file_get_contents($cacheFile);
+                @flock($fp, LOCK_UN);
+                @fclose($fp);
+                return $cacheValue;
+            }
         }
+
+        return false;
     }
 
     /**