From f49d36b719787eb8ef0c1ccb0433f4e150bfa677 Mon Sep 17 00:00:00 2001
From: Andrew Steinborn <git@steinborn.me>
Date: Sun, 12 Apr 2020 17:05:36 -0400
Subject: [PATCH] Close one last "proxy crasher" loophole

---
 .../proxy/connection/MinecraftConnection.java        | 12 +++++++++++-
 1 file changed, 11 insertions(+), 1 deletion(-)

diff --git a/proxy/src/main/java/com/velocitypowered/proxy/connection/MinecraftConnection.java b/proxy/src/main/java/com/velocitypowered/proxy/connection/MinecraftConnection.java
index 8d2e4c895..dc1151fe8 100644
--- a/proxy/src/main/java/com/velocitypowered/proxy/connection/MinecraftConnection.java
+++ b/proxy/src/main/java/com/velocitypowered/proxy/connection/MinecraftConnection.java
@@ -152,7 +152,7 @@ public class MinecraftConnection extends ChannelInboundHandlerAdapter {
         }
       }
 
-      ctx.pipeline().addBefore(MINECRAFT_DECODER, "discard", DiscardHandler.HANDLER);
+      installDiscardHandler(ctx);
       ctx.close();
     }
   }
@@ -168,6 +168,14 @@ public class MinecraftConnection extends ChannelInboundHandlerAdapter {
     Preconditions.checkState(this.channel.eventLoop().inEventLoop(), "Not in event loop");
   }
 
+  private void installDiscardHandler(ChannelHandlerContext ctx) {
+    ctx.pipeline().addBefore(MINECRAFT_DECODER, "discard", DiscardHandler.HANDLER);
+  }
+
+  private void installDiscardHandler() {
+    channel.pipeline().addBefore(MINECRAFT_DECODER, "discard", DiscardHandler.HANDLER);
+  }
+
   public EventLoop eventLoop() {
     return channel.eventLoop();
   }
@@ -208,6 +216,7 @@ public class MinecraftConnection extends ChannelInboundHandlerAdapter {
   public void closeWith(Object msg) {
     if (channel.isActive()) {
       knownDisconnect = true;
+      installDiscardHandler();
       channel.writeAndFlush(msg).addListener(ChannelFutureListener.CLOSE);
     }
   }
@@ -217,6 +226,7 @@ public class MinecraftConnection extends ChannelInboundHandlerAdapter {
    */
   public void close() {
     if (channel.isActive()) {
+      installDiscardHandler();
       channel.close();
     }
   }