PaperMC/patches/server/0691-Reset-placed-block-on-exception.patch
Owen 89d51d5f29
Allow enabling sand duping (#10191)
Because this exploit has been widely known for years and has not been fixed by Mojang, we decided that it was worth allowing people to toggle it on/off due to how easy it is to make it configurable.

It should be noted that this decision does not promise all future exploits will be configurable.
2024-03-03 17:05:34 -05:00

38 lines
2.6 KiB
Diff

From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Nassim Jahnke <nassim@njahnke.dev>
Date: Fri, 7 Jan 2022 11:45:15 +0100
Subject: [PATCH] Reset placed block on exception
diff --git a/src/main/java/net/minecraft/world/item/BlockItem.java b/src/main/java/net/minecraft/world/item/BlockItem.java
index c19069f65a9ecbc9000ea4333417a2df4ace1007..1ac739c92031e80c35e1af4417e6358346079580 100644
--- a/src/main/java/net/minecraft/world/item/BlockItem.java
+++ b/src/main/java/net/minecraft/world/item/BlockItem.java
@@ -80,6 +80,7 @@ public class BlockItem extends Item {
if (this instanceof PlaceOnWaterBlockItem || this instanceof SolidBucketItem) {
blockstate = org.bukkit.craftbukkit.block.CraftBlockStates.getBlockState(blockactioncontext1.getLevel(), blockactioncontext1.getClickedPos());
}
+ final org.bukkit.block.BlockState oldBlockstate = blockstate != null ? blockstate : org.bukkit.craftbukkit.block.CraftBlockStates.getBlockState(blockactioncontext1.getLevel(), blockactioncontext1.getClickedPos()); // Paper - Reset placed block on exception
// CraftBukkit end
if (iblockdata == null) {
@@ -95,7 +96,19 @@ public class BlockItem extends Item {
if (iblockdata1.is(iblockdata.getBlock())) {
iblockdata1 = this.updateBlockStateFromTag(blockposition, world, itemstack, iblockdata1);
+ // Paper start - Reset placed block on exception
+ try {
this.updateCustomBlockEntityTag(blockposition, world, entityhuman, itemstack, iblockdata1);
+ } catch (Exception e) {
+ oldBlockstate.update(true, false);
+ if (entityhuman instanceof ServerPlayer player) {
+ org.apache.logging.log4j.LogManager.getLogger().error("Player {} tried placing invalid block", player.getScoreboardName(), e);
+ player.getBukkitEntity().kickPlayer("Packet processing error");
+ return InteractionResult.FAIL;
+ }
+ throw e; // Rethrow exception if not placed by a player
+ }
+ // Paper end - Reset placed block on exception
iblockdata1.getBlock().setPlacedBy(world, blockposition, iblockdata1, entityhuman, itemstack);
// CraftBukkit start
if (blockstate != null) {