Always check variable type before using readdir to avoid surprises

2 files changed, 20 insertions, 11 deletions

diff --git a/lib/cache/file.php b/lib/cache/file.php
index 9fee6034a71..361138e4736 100644
--- a/lib/cache/file.php
+++ b/lib/cache/file.php
@@ -80,9 +80,11 @@ class OC_Cache_File{
 		$storage = $this->getStorage();
 		if($storage and $storage->is_dir('/')) {
 			$dh=$storage->opendir('/');
-			while (($file = readdir($dh)) !== false) {
-				if($file!='.' and $file!='..' and ($prefix==='' || strpos($file, $prefix) === 0)) {
-					$storage->unlink('/'.$file);
+			if(is_resource($dh)) {
+				while (($file = readdir($dh)) !== false) {
+					if($file!='.' and $file!='..' and ($prefix==='' || strpos($file, $prefix) === 0)) {
+						$storage->unlink('/'.$file);
+					}
 				}
 			}
 		}
@@ -94,6 +96,9 @@ class OC_Cache_File{
 		if($storage and $storage->is_dir('/')) {
 			$now = time();
 			$dh=$storage->opendir('/');
+			if(!is_resource($dh)) {
+				return null;
+			}
 			while (($file = readdir($dh)) !== false) {
 				if($file!='.' and $file!='..') {
 					$mtime = $storage->filemtime('/'.$file);
diff --git a/lib/cache/fileglobal.php b/lib/cache/fileglobal.php
index 2fbd8ca3edb..c0bd8e45f39 100644
--- a/lib/cache/fileglobal.php
+++ b/lib/cache/fileglobal.php
@@ -69,9 +69,11 @@ class OC_Cache_FileGlobal{
 		$prefix = $this->fixKey($prefix);
 		if($cache_dir and is_dir($cache_dir)) {
 			$dh=opendir($cache_dir);
-			while (($file = readdir($dh)) !== false) {
-				if($file!='.' and $file!='..' and ($prefix==='' || strpos($file, $prefix) === 0)) {
-					unlink($cache_dir.$file);
+			if(is_resource($dh)) {
+				while (($file = readdir($dh)) !== false) {
+					if($file!='.' and $file!='..' and ($prefix==='' || strpos($file, $prefix) === 0)) {
+						unlink($cache_dir.$file);
+					}
 				}
 			}
 		}
@@ -88,11 +90,13 @@ class OC_Cache_FileGlobal{
 		$cache_dir = self::getCacheDir();
 		if($cache_dir and is_dir($cache_dir)) {
 			$dh=opendir($cache_dir);
-			while (($file = readdir($dh)) !== false) {
-				if($file!='.' and $file!='..') {
-					$mtime = filemtime($cache_dir.$file);
-					if ($mtime < $now) {
-						unlink($cache_dir.$file);
+			if(is_resource($dh)) {
+				while (($file = readdir($dh)) !== false) {
+					if($file!='.' and $file!='..') {
+						$mtime = filemtime($cache_dir.$file);
+						if ($mtime < $now) {
+							unlink($cache_dir.$file);
+						}
 					}
 				}
 			}