31 lines
		
	
	
	
		
			1.9 KiB
			
		
	
	
	
		
			Diff
		
	
	
	
	
	
			
		
		
	
	
			31 lines
		
	
	
	
		
			1.9 KiB
			
		
	
	
	
		
			Diff
		
	
	
	
	
	
From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
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From: Spottedleaf <Spottedleaf@users.noreply.github.com>
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Date: Fri, 12 Jun 2020 16:51:39 -0700
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Subject: [PATCH] Prevent position desync in playerconnection causing tp
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 exploit
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Caused the server to revert to the player's overworld coordinates
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after teleporting into the end.
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Sidenote: The underlying issue is that the move call can teleport
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entities and do other things like kill the entity. In the future,
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to fix all exploits derieved from this usually unexpected
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behaviour, we need to move all of this dangerous logic outside
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of the move call and into an appropriate place in the tick method.
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diff --git a/src/main/java/net/minecraft/server/network/ServerGamePacketListenerImpl.java b/src/main/java/net/minecraft/server/network/ServerGamePacketListenerImpl.java
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index 0000000000000000000000000000000000000000..0000000000000000000000000000000000000000 100644
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--- a/src/main/java/net/minecraft/server/network/ServerGamePacketListenerImpl.java
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+++ b/src/main/java/net/minecraft/server/network/ServerGamePacketListenerImpl.java
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@@ -0,0 +0,0 @@ public class ServerGamePacketListenerImpl implements ServerPlayerConnection, Ser
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                             this.player.move(MoverType.PLAYER, new Vec3(d7, d8, d9));
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                             this.player.onGround = packet.isOnGround(); // CraftBukkit - SPIGOT-5810, SPIGOT-5835, SPIGOT-6828: reset by this.player.move
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+                            // Paper start - prevent position desync
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+                            if (this.awaitingPositionFromClient != null) {
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+                                return; // ... thanks Mojang for letting move calls teleport across dimensions.
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+                            }
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+                            // Paper end - prevent position desync
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                             double d12 = d8;
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                             d7 = d0 - this.player.getX();
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