From 04eb83fd24ed63bb6dcd8b7b2fedeec27b3a944d Mon Sep 17 00:00:00 2001
From: Aikar <aikar@aikar.co>
Date: Wed, 21 Mar 2018 20:52:07 -0400
Subject: [PATCH] Fix Dragon Server Crashes

If the dragon tries to find "ground" and hits a hole, or off edge,
it will infinitely keep looking for non air and eventually crash.

diff --git a/src/main/java/net/minecraft/server/DragonControllerLandedFlame.java b/src/main/java/net/minecraft/server/DragonControllerLandedFlame.java
index cfe84f4d4..4ab310cd6 100644
--- a/src/main/java/net/minecraft/server/DragonControllerLandedFlame.java
+++ b/src/main/java/net/minecraft/server/DragonControllerLandedFlame.java
@@ -53,7 +53,7 @@ public class DragonControllerLandedFlame extends AbstractDragonControllerLanded
             double d2 = this.a.bA.locY + (double) (this.a.bA.getHeight() / 2.0F);
             BlockPosition.MutableBlockPosition blockposition_mutableblockposition = new BlockPosition.MutableBlockPosition(d0, d2, d1);
 
-            while (this.a.world.isEmpty(blockposition_mutableblockposition)) {
+            while (this.a.world.isEmpty(blockposition_mutableblockposition ) && d2 > 0) { // Paper
                 --d2;
                 blockposition_mutableblockposition.c(d0, d2, d1);
             }
-- 
2.22.0