papermc/Spigot-Server-Patches/0495-Validate-PickItem-Packet-and-kick-for-invalid.patch
Aikar 70ad51a80c
Updated Upstream (Bukkit/CraftBukkit)
Upstream has released updates that appears to apply and compile correctly.
This update has not been tested by PaperMC and as with ANY update, please do your own testing

My recent work on serialization is now in CraftBukkit so was able to drop the patch and Paper
is now consistent with upstream.

Bukkit Changes:
e2699636 Move API notes to more obvious location

CraftBukkit Changes:
1b2830a3 SPIGOT-4441: Fix serializing Components to and from Legacy
2020-06-02 01:29:18 -04:00

26 lines
1.8 KiB
Diff

From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Aikar <aikar@aikar.co>
Date: Sat, 2 May 2020 03:09:46 -0400
Subject: [PATCH] Validate PickItem Packet and kick for invalid
diff --git a/src/main/java/net/minecraft/server/PlayerConnection.java b/src/main/java/net/minecraft/server/PlayerConnection.java
index c2f2671da9b3598c2f866db1078d4b1d0f3430ef..294e9a47e21be0babad2ea3d2a9b3fc79083e350 100644
--- a/src/main/java/net/minecraft/server/PlayerConnection.java
+++ b/src/main/java/net/minecraft/server/PlayerConnection.java
@@ -696,7 +696,14 @@ public class PlayerConnection implements PacketListenerPlayIn {
@Override
public void a(PacketPlayInPickItem packetplayinpickitem) {
PlayerConnectionUtils.ensureMainThread(packetplayinpickitem, this, this.player.getWorldServer());
- this.player.inventory.c(packetplayinpickitem.b());
+ // Paper start - validate pick item position
+ if (!(packetplayinpickitem.b() >= 0 && packetplayinpickitem.b() < this.player.inventory.items.size())) {
+ PlayerConnection.LOGGER.warn("{} tried to set an invalid carried item", this.player.getDisplayName().getString());
+ this.disconnect("Invalid hotbar selection (Hacking?)");
+ return;
+ }
+ this.player.inventory.c(packetplayinpickitem.b()); // Paper - Diff above if changed
+ // Paper end
this.player.playerConnection.sendPacket(new PacketPlayOutSetSlot(-2, this.player.inventory.itemInHandIndex, this.player.inventory.getItem(this.player.inventory.itemInHandIndex)));
this.player.playerConnection.sendPacket(new PacketPlayOutSetSlot(-2, packetplayinpickitem.b(), this.player.inventory.getItem(packetplayinpickitem.b())));
this.player.playerConnection.sendPacket(new PacketPlayOutHeldItemSlot(this.player.inventory.itemInHandIndex));