From 6a683dcf7780aa2e1544c470a8b5a4953fc13349 Mon Sep 17 00:00:00 2001
From: Spaceman1984 <49917670+Spaceman1984@users.noreply.github.com>
Date: Mon, 15 Jun 2020 06:24:22 +0200
Subject: [PATCH] storage: Fixed null pointer (#4130)

Fixes #4090

When trying to migrate a VM across 2 clusters, if a snapshot has been deleted and garbage collection has run to update the removed field, it is not possible to migrate the instance due to a null pointer.
---
 .../cloudstack/storage/snapshot/SnapshotDataFactoryImpl.java   | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/engine/storage/snapshot/src/main/java/org/apache/cloudstack/storage/snapshot/SnapshotDataFactoryImpl.java b/engine/storage/snapshot/src/main/java/org/apache/cloudstack/storage/snapshot/SnapshotDataFactoryImpl.java
index 11d61df3d7f..f8be1adee56 100644
--- a/engine/storage/snapshot/src/main/java/org/apache/cloudstack/storage/snapshot/SnapshotDataFactoryImpl.java
+++ b/engine/storage/snapshot/src/main/java/org/apache/cloudstack/storage/snapshot/SnapshotDataFactoryImpl.java
@@ -73,6 +73,9 @@ public class SnapshotDataFactoryImpl implements SnapshotDataFactory {
         for (SnapshotDataStoreVO snapshotDataStoreVO : allSnapshotsFromVolumeAndDataStore) {
             DataStore store = storeMgr.getDataStore(snapshotDataStoreVO.getDataStoreId(), role);
             SnapshotVO snapshot = snapshotDao.findById(snapshotDataStoreVO.getSnapshotId());
+            if (snapshot == null){ //snapshot may have been removed;
+                continue;
+            }
             SnapshotObject info = SnapshotObject.getSnapshotObject(snapshot, store);
 
             infos.add(info);