PaperMC/patches/server/0939-Do-not-read-tile-entities-in-chunks-that-are-positio.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

50 lines
3.2 KiB
Diff

From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Spottedleaf <Spottedleaf@users.noreply.github.com>
Date: Sun, 18 Jun 2023 23:04:46 -0700
Subject: [PATCH] Do not read tile entities in chunks that are positioned
outside of the chunk
The tile entities are not accessible and so should not be loaded.
This can happen as a result of users moving regionfiles around,
which would cause a crash on Folia but would appear to function
fine on Paper.
diff --git a/src/main/java/net/minecraft/world/level/chunk/storage/ChunkSerializer.java b/src/main/java/net/minecraft/world/level/chunk/storage/ChunkSerializer.java
index 3b046dc106b96b7ca2b148d605e8b7c97453d033..85de64c1e75e1323f8425fc53e525c215ff417ce 100644
--- a/src/main/java/net/minecraft/world/level/chunk/storage/ChunkSerializer.java
+++ b/src/main/java/net/minecraft/world/level/chunk/storage/ChunkSerializer.java
@@ -307,6 +307,13 @@ public class ChunkSerializer {
for (int k1 = 0; k1 < nbttaglist3.size(); ++k1) {
CompoundTag nbttagcompound4 = nbttaglist3.getCompound(k1);
+ // Paper start - do not read tile entities positioned outside the chunk
+ BlockPos blockposition = BlockEntity.getPosFromTag(nbttagcompound4);
+ if ((blockposition.getX() >> 4) != chunkPos.x || (blockposition.getZ() >> 4) != chunkPos.z) {
+ LOGGER.warn("Tile entity serialized in chunk " + chunkPos + " in world '" + world.getWorld().getName() + "' positioned at " + blockposition + " is located outside of the chunk");
+ continue;
+ }
+ // Paper end - do not read tile entities positioned outside the chunk
((ChunkAccess) object1).setBlockEntityNbt(nbttagcompound4);
}
@@ -517,10 +524,19 @@ public class ChunkSerializer {
CompoundTag nbttagcompound1 = nbttaglist1.getCompound(i);
boolean flag = nbttagcompound1.getBoolean("keepPacked");
+ // Paper start - do not read tile entities positioned outside the chunk
+ BlockPos blockposition = BlockEntity.getPosFromTag(nbttagcompound1); // moved up
+ ChunkPos chunkPos = chunk.getPos();
+ if ((blockposition.getX() >> 4) != chunkPos.x || (blockposition.getZ() >> 4) != chunkPos.z) {
+ LOGGER.warn("Tile entity serialized in chunk " + chunkPos + " in world '" + world.getWorld().getName() + "' positioned at " + blockposition + " is located outside of the chunk");
+ continue;
+ }
+ // Paper end - do not read tile entities positioned outside the chunk
+
if (flag) {
chunk.setBlockEntityNbt(nbttagcompound1);
} else {
- BlockPos blockposition = BlockEntity.getPosFromTag(nbttagcompound1);
+ // Paper - do not read tile entities positioned outside the chunk; move up
BlockEntity tileentity = BlockEntity.loadStatic(blockposition, chunk.getBlockState(blockposition), nbttagcompound1);
if (tileentity != null) {