From ae0ea2e242427ad80f04f4fcab1dc685ba417c47 Mon Sep 17 00:00:00 2001
From: Aleksander Machniak <machniak@kolabsys.com>
Date: Thu, 10 Mar 2016 16:43:10 +0100
Subject: [PATCH] Prevent from fatal errors on events without end date (#5307)

---
 plugins/libkolab/lib/kolab_date_recurrence.php | 7 +++++--
 plugins/libkolab/lib/kolab_format_event.php    | 4 ++++
 2 files changed, 9 insertions(+), 2 deletions(-)

diff --git a/plugins/libkolab/lib/kolab_date_recurrence.php b/plugins/libkolab/lib/kolab_date_recurrence.php
index f2483c96..4f8ae61a 100644
--- a/plugins/libkolab/lib/kolab_date_recurrence.php
+++ b/plugins/libkolab/lib/kolab_date_recurrence.php
@@ -49,8 +49,11 @@ class kolab_date_recurrence
 
         if (is_object($data['start']) && is_object($data['end']))
             $this->duration = $data['start']->diff($data['end']);
-        else
-            $this->duration = new DateInterval('PT' . ($data['end'] - $data['start']) . 'S');
+        else {
+            // Prevent from errors when end date is not set (#5307) RFC5545 3.6.1
+            $seconds = !empty($data['end']) ? ($data['end'] - $data['start']) : 0;
+            $this->duration = new DateInterval('PT' . $seconds . 'S');
+        }
     }
 
     /**
diff --git a/plugins/libkolab/lib/kolab_format_event.php b/plugins/libkolab/lib/kolab_format_event.php
index 41a9745b..a7cf2d42 100644
--- a/plugins/libkolab/lib/kolab_format_event.php
+++ b/plugins/libkolab/lib/kolab_format_event.php
@@ -189,6 +189,10 @@ class kolab_format_event extends kolab_format_xcal
             $object['end'] = clone $object['start'];
             $object['end']->add($interval);
         }
+        // make sure end date is specified (#5307) RFC5545 3.6.1
+        else if (!$object['end'] && $object['start']) {
+            $object['end'] = clone $object['start'];
+        }
 
         // organizer is part of the attendees list in Roundcube
         if ($object['organizer']) {