From a615e7dcfa71bfe5cf47ac32817a53ec1404f10d Mon Sep 17 00:00:00 2001
From: Arthur Schiwon <blizzz@arthur-schiwon.de>
Date: Fri, 16 Oct 2020 12:29:35 +0200
Subject: [PATCH] fixes potential passing of null to getUserGroupIds

Signed-off-by: Arthur Schiwon <blizzz@arthur-schiwon.de>
---
 lib/private/Share20/DefaultShareProvider.php | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/private/Share20/DefaultShareProvider.php b/lib/private/Share20/DefaultShareProvider.php
index ecfe282dfb..e43529086f 100644
--- a/lib/private/Share20/DefaultShareProvider.php
+++ b/lib/private/Share20/DefaultShareProvider.php
@@ -881,7 +881,7 @@ class DefaultShareProvider implements IShareProvider {
 			$cursor->closeCursor();
 		} elseif ($shareType === IShare::TYPE_GROUP) {
 			$user = $this->userManager->get($userId);
-			$allGroups = $this->groupManager->getUserGroupIds($user);
+			$allGroups = ($user instanceof IUser) ? $this->groupManager->getUserGroupIds($user) : [];
 
 			/** @var Share[] $shares2 */
 			$shares2 = [];