check that we know the parent

diff --git a/apps/files_sharing/lib/cache.php b/apps/files_sharing/lib/cache.php
index 187d3f38afcc7dc981c60d5cde2916c2c49a1ab2..2f982ec9dc6e0e536fbf88ac30009d800f6de016 100644 (file)
--- a/apps/files_sharing/lib/cache.php
+++ b/apps/files_sharing/lib/cache.php
@@ -415,9 +415,11 @@ class Shared_Cache extends Cache {
                } else {
                        // bubble up to source cache
                        $sourceCache = $this->getSourceCache($path);
-                       $parent = dirname($this->files[$path]);
-                       if ($sourceCache) {
-                               $sourceCache->correctFolderSize($parent);
+                       if (isset($this->files[$path])) {
+                               $parent = dirname($this->files[$path]);
+                               if ($sourceCache) {
+                                       $sourceCache->correctFolderSize($parent);
+                               }
                        }
                }
        }