diff --git a/apps/files_external/lib/amazons3.php b/apps/files_external/lib/amazons3.php
index c08a266b48c23d36e897cae68b319af36d4963df..9a682fb2d48548696b6f862c116badf3a1d5fea2 100644
--- a/apps/files_external/lib/amazons3.php
+++ b/apps/files_external/lib/amazons3.php
@@ -300,14 +300,6 @@ class AmazonS3 extends \OC\Files\Storage\Common {
 		return false;
 	}
 
-	public function isReadable($path) {
-		return true;
-	}
-
-	public function isUpdatable($path) {
-		return true;
-	}
-
 	public function unlink($path) {
 		$path = $this->normalizePath($path);
 
diff --git a/apps/files_external/lib/dropbox.php b/apps/files_external/lib/dropbox.php
index b6deab6e5a712e93805cc6ad2f97092e82268b05..6e464f4e28715037cb1653fc6d9056e8af74ab10 100755
--- a/apps/files_external/lib/dropbox.php
+++ b/apps/files_external/lib/dropbox.php
@@ -146,14 +146,6 @@ class Dropbox extends \OC\Files\Storage\Common {
 		return false;
 	}
 
-	public function isReadable($path) {
-		return $this->file_exists($path);
-	}
-
-	public function isUpdatable($path) {
-		return $this->file_exists($path);
-	}
-
 	public function file_exists($path) {
 		if ($path == '' || $path == '/') {
 			return true;
diff --git a/apps/files_external/lib/google.php b/apps/files_external/lib/google.php
index b63b5885de1ac80287c334e3e821b8c8523e7390..426caf008ecb39795c0578678090b2c667e721b4 100644
--- a/apps/files_external/lib/google.php
+++ b/apps/files_external/lib/google.php
@@ -317,10 +317,6 @@ class Google extends \OC\Files\Storage\Common {
 		}
 	}
 
-	public function isReadable($path) {
-		return $this->file_exists($path);
-	}
-
 	public function isUpdatable($path) {
 		$file = $this->getDriveFile($path);
 		if ($file) {
diff --git a/apps/files_external/lib/sftp.php b/apps/files_external/lib/sftp.php
index 7c5aed5aa06b04f21e69077c28f3dc17352a6a7a..bcc4c5eafd545533bdafe33f7aede3617f896bec 100644
--- a/apps/files_external/lib/sftp.php
+++ b/apps/files_external/lib/sftp.php
@@ -180,14 +180,6 @@ class SFTP extends \OC\Files\Storage\Common {
 		return false;
 	}
 
-	public function isReadable($path) {
-		return true;
-	}
-
-	public function isUpdatable($path) {
-		return true;
-	}
-
 	public function file_exists($path) {
 		try {
 			return $this->client->stat($this->absPath($path)) !== false;
diff --git a/apps/files_external/lib/streamwrapper.php b/apps/files_external/lib/streamwrapper.php
index a086f411f573b0005c53d82ca9df9e1699687043..23c5f91a2f33b8ab25f710f95b9b7d88f4ea4412 100644
--- a/apps/files_external/lib/streamwrapper.php
+++ b/apps/files_external/lib/streamwrapper.php
@@ -41,19 +41,6 @@ abstract class StreamWrapper extends Common {
 		return filetype($this->constructUrl($path));
 	}
 
-	public function isReadable($path) {
-		// at least check whether it exists
-		// subclasses might want to implement this more thoroughly
-		return $this->file_exists($path);
-	}
-
-	public function isUpdatable($path) {
-		// at least check whether it exists
-		// subclasses might want to implement this more thoroughly
-		// a non-existing file/folder isn't updatable
-		return $this->file_exists($path);
-	}
-
 	public function file_exists($path) {
 		return file_exists($this->constructUrl($path));
 	}
diff --git a/apps/files_external/lib/swift.php b/apps/files_external/lib/swift.php
index bb650dacc7b0a4ae2c7c45060b1374bc29bafbd5..86938ef3bb9c59c82c450c057a61e045adc2941c 100644
--- a/apps/files_external/lib/swift.php
+++ b/apps/files_external/lib/swift.php
@@ -268,14 +268,6 @@ class Swift extends \OC\Files\Storage\Common {
 		}
 	}
 
-	public function isReadable($path) {
-		return true;
-	}
-
-	public function isUpdatable($path) {
-		return true;
-	}
-
 	public function unlink($path) {
 		$path = $this->normalizePath($path);
 
diff --git a/apps/files_external/lib/webdav.php b/apps/files_external/lib/webdav.php
index 5857c59dcfc092ef7b72b1b8532b1560e3dc7cc7..0837222e51103f78c1dfcf44d2a45410804f53c3 100644
--- a/apps/files_external/lib/webdav.php
+++ b/apps/files_external/lib/webdav.php
@@ -134,14 +134,6 @@ class DAV extends \OC\Files\Storage\Common{
 		}
 	}
 
-	public function isReadable($path) {
-		return true;//not properly supported
-	}
-
-	public function isUpdatable($path) {
-		return true;//not properly supported
-	}
-
 	public function file_exists($path) {
 		$this->init();
 		$path=$this->cleanPath($path);
diff --git a/lib/private/files/storage/common.php b/lib/private/files/storage/common.php
index f99bbc9ae5e386f4015733ecfafc55c07220d60b..678bf4190239c0e3dc5e96cea7fa40d67d1b0204 100644
--- a/lib/private/files/storage/common.php
+++ b/lib/private/files/storage/common.php
@@ -51,6 +51,19 @@ abstract class Common implements \OC\Files\Storage\Storage {
 		}
 	}
 
+	public function isReadable($path) {
+		// at least check whether it exists
+		// subclasses might want to implement this more thoroughly
+		return $this->file_exists($path);
+	}
+
+	public function isUpdatable($path) {
+		// at least check whether it exists
+		// subclasses might want to implement this more thoroughly
+		// a non-existing file/folder isn't updatable
+		return $this->file_exists($path);
+	}
+
 	public function isCreatable($path) {
 		if ($this->is_dir($path) && $this->isUpdatable($path)) {
 			return true;