spigot/CraftBukkit-Patches/0046-Fix-race-condition-that-could-kill-connections-befor.patch

From c0eb4a50b076f77a85b9215255a1d02be4a448c6 Mon Sep 17 00:00:00 2001
From: Jonas Konrad <me@yawk.at>
Date: Fri, 25 Apr 2014 23:46:46 +0200
Subject: [PATCH] Fix race condition that could kill connections before they
 were initiated

Because NetworkManagers are registered before they get their channel in
channelActive, the ServerConnection would remove them sometimes because
it thought they were disconnected. This commit fixes this by introducing
a 'preparing' variable that is true while the NetworkManager is not
initialized. The ServerConnection does not remove NetworkManagers with
this flag.

diff --git a/src/main/java/net/minecraft/network/NetworkManager.java b/src/main/java/net/minecraft/network/NetworkManager.java
index 4ea9b2bfcf..1cae281e6d 100644
--- a/src/main/java/net/minecraft/network/NetworkManager.java
+++ b/src/main/java/net/minecraft/network/NetworkManager.java
@@ -99,6 +99,7 @@ public class NetworkManager extends SimpleChannelInboundHandler<Packet<?>> {
     // Spigot Start
     public java.util.UUID spoofedUUID;
     public com.mojang.authlib.properties.Property[] spoofedProfile;
+    public boolean preparing = true;
     // Spigot End
     @Nullable
     private volatile PacketListener disconnectListener;
@@ -128,6 +129,9 @@ public class NetworkManager extends SimpleChannelInboundHandler<Packet<?>> {
         super.channelActive(channelhandlercontext);
         this.channel = channelhandlercontext.channel();
         this.address = this.channel.remoteAddress();
+        // Spigot Start
+        this.preparing = false;
+        // Spigot End
         if (this.delayedDisconnect != null) {
             this.disconnect(this.delayedDisconnect);
         }
@@ -470,6 +474,9 @@ public class NetworkManager extends SimpleChannelInboundHandler<Packet<?>> {
     }
 
     public void disconnect(DisconnectionDetails disconnectiondetails) {
+        // Spigot Start
+        this.preparing = false;
+        // Spigot End
         if (this.channel == null) {
             this.delayedDisconnect = disconnectiondetails;
         }
diff --git a/src/main/java/net/minecraft/server/network/ServerConnection.java b/src/main/java/net/minecraft/server/network/ServerConnection.java
index 85fb253c16..b66b9e5c27 100644
--- a/src/main/java/net/minecraft/server/network/ServerConnection.java
+++ b/src/main/java/net/minecraft/server/network/ServerConnection.java
@@ -193,6 +193,10 @@ public class ServerConnection {
                             networkmanager.setReadOnly();
                         }
                     } else {
+                        // Spigot Start
+                        // Fix a race condition where a NetworkManager could be unregistered just before connection.
+                        if (networkmanager.preparing) continue;
+                        // Spigot End
                         iterator.remove();
                         networkmanager.handleDisconnection();
                     }
-- 
2.47.0