From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Spottedleaf <Spottedleaf@users.noreply.github.com>
Date: Tue, 24 Sep 2019 16:03:00 -0700
Subject: [PATCH] Fix MC-161754

Fixes https://github.com/PaperMC/Paper/issues/2580

We can use an entity valid check since this method is invoked for
each inventory iteraction (thanks to CB) and on player tick (vanilla).

diff --git a/src/main/java/net/minecraft/server/ContainerHorse.java b/src/main/java/net/minecraft/server/ContainerHorse.java
index 82109f50778a3ac4bea43ef83b5442105a45664a..ebaf45be997d121e1974dc1f920dccbf11744cb3 100644
--- a/src/main/java/net/minecraft/server/ContainerHorse.java
+++ b/src/main/java/net/minecraft/server/ContainerHorse.java
@@ -76,7 +76,7 @@ public class ContainerHorse extends Container {
 
     @Override
     public boolean canUse(EntityHuman entityhuman) {
-        return this.c.a(entityhuman) && this.d.isAlive() && this.d.g((Entity) entityhuman) < 8.0F;
+        return this.c.a(entityhuman) && (this.d.isAlive() && this.d.valid) && this.d.g((Entity) entityhuman) < 8.0F; // Paper - Fix MC-161754
     }
 
     @Override