From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001 From: Zach Brown Date: Tue, 23 Jul 2019 20:44:47 -0500 Subject: [PATCH] Do not let the server load chunks from newer versions If the server attempts to load a chunk generated by a newer version of the game, immediately stop the server to prevent data corruption. You can override this functionality at your own peril. 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 b3f8df13e97cbde7dd914b42004d186f90b78646..2ca1f01ab59000949cbde1766c9811a72dbfb4ff 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 @@ -86,6 +86,10 @@ public class ChunkSerializer { public static final String BLOCK_LIGHT_TAG = "BlockLight"; public static final String SKY_LIGHT_TAG = "SkyLight"; + // Paper start - Do not let the server load chunks from newer versions + private static final int CURRENT_DATA_VERSION = net.minecraft.SharedConstants.getCurrentVersion().getDataVersion().getVersion(); + private static final boolean JUST_CORRUPT_IT = Boolean.getBoolean("Paper.ignoreWorldDataVersion"); + // Paper end - Do not let the server load chunks from newer versions public ChunkSerializer() {} // Paper start - guard against serializing mismatching coordinates @@ -101,6 +105,15 @@ public class ChunkSerializer { } // Paper end - guard against serializing mismatching coordinates public static ProtoChunk read(ServerLevel world, PoiManager poiStorage, ChunkPos chunkPos, CompoundTag nbt) { + // Paper start - Do not let the server load chunks from newer versions + if (nbt.contains("DataVersion", net.minecraft.nbt.Tag.TAG_ANY_NUMERIC)) { + final int dataVersion = nbt.getInt("DataVersion"); + if (!JUST_CORRUPT_IT && dataVersion > CURRENT_DATA_VERSION) { + new RuntimeException("Server attempted to load chunk saved with newer version of minecraft! " + dataVersion + " > " + CURRENT_DATA_VERSION).printStackTrace(); + System.exit(1); + } + } + // Paper end - Do not let the server load chunks from newer versions ChunkPos chunkcoordintpair1 = new ChunkPos(nbt.getInt("xPos"), nbt.getInt("zPos")); // Paper - guard against serializing mismatching coordinates; diff on change, see ChunkSerializer#getChunkCoordinate if (!Objects.equals(chunkPos, chunkcoordintpair1)) {