From 085bcd7da27e82e4695ff1a2cf961e9b6a820712 Mon Sep 17 00:00:00 2001
From: Vincent Petry <pvince81@owncloud.com>
Date: Fri, 22 Apr 2016 11:10:51 +0200
Subject: [PATCH] Throw NoUserException when attempting to init mount point for
 null user

In some scenarios initMountPoints is called with an empty user, and
also there is no user in the session.

In such cases, it is unsafe to let the code move on with an empty user.
---
 lib/private/files/filesystem.php |  3 +++
 tests/lib/files/filesystem.php   | 22 ++++++++++++++++++++++
 2 files changed, 25 insertions(+)

diff --git a/lib/private/files/filesystem.php b/lib/private/files/filesystem.php
index a9138b0d2d..ec9b537a35 100644
--- a/lib/private/files/filesystem.php
+++ b/lib/private/files/filesystem.php
@@ -372,6 +372,9 @@ class Filesystem {
 		if ($user == '') {
 			$user = \OC_User::getUser();
 		}
+		if ($user === null || $user === false || $user === '') {
+			throw new \OC\User\NoUserException('Attempted to initialize mount points for null user and no user in session');
+		}
 		if (isset(self::$usersSetup[$user])) {
 			return;
 		}
diff --git a/tests/lib/files/filesystem.php b/tests/lib/files/filesystem.php
index db1f22f894..8245af0ace 100644
--- a/tests/lib/files/filesystem.php
+++ b/tests/lib/files/filesystem.php
@@ -319,6 +319,28 @@ class Filesystem extends \Test\TestCase {
 		\OC\Files\Filesystem::initMountPoints($userId);
 	}
 
+	/**
+	 * @expectedException \OC\User\NoUserException
+	 */
+	public function testNullUserThrows() {
+		\OC\Files\Filesystem::initMountPoints(null);
+	}
+
+	public function testNullUserThrowsTwice() {
+		$thrown = 0;
+		try {
+			\OC\Files\Filesystem::initMountPoints(null);
+		} catch (NoUserException $e) {
+			$thrown++;
+		}
+		try {
+			\OC\Files\Filesystem::initMountPoints(null);
+		} catch (NoUserException $e) {
+			$thrown++;
+		}
+		$this->assertEquals(2, $thrown);
+	}
+
 	/**
 	 * Tests that the home storage is used for the user's mount point
 	 */