1 files changed, 51 insertions, 21 deletions

diff --git a/src/WorldStorage/WSSAnvil.cpp b/src/WorldStorage/WSSAnvil.cpp
index 5c155aeef..10cc39083 100644
--- a/src/WorldStorage/WSSAnvil.cpp
+++ b/src/WorldStorage/WSSAnvil.cpp
@@ -66,8 +66,17 @@ Since only the header is actually in the memory, this number can be high, but st
 */
 #define MAX_MCA_FILES 32
 
-/// The maximum size of an inflated chunk; raw chunk data is 192 KiB, allow 64 KiB more of entities
-#define CHUNK_INFLATE_MAX 256 KiB
+#define LOAD_FAILED(CHX, CHZ) \
+	{ \
+		const int RegionX = FAST_FLOOR_DIV(CHX, 32); \
+		const int RegionZ = FAST_FLOOR_DIV(CHZ, 32); \
+		LOGERROR("%s (%d): Loading chunk [%d, %d] from file r.%d.%d.mca failed. " \
+			"The server will now abort in order to avoid further data loss. " \
+			"Please add the reported file and this message to the issue report.", \
+			__FUNCTION__, __LINE__, CHX, CHZ, RegionX, RegionZ \
+		); \
+		*((volatile int *)0) = 0;  /* Crash intentionally */ \
+	}
 
 
 
@@ -248,29 +257,22 @@ cWSSAnvil::cMCAFile * cWSSAnvil::LoadMCAFile(const cChunkCoords & a_Chunk)
 
 bool cWSSAnvil::LoadChunkFromData(const cChunkCoords & a_Chunk, const AString & a_Data)
 {
-	// Decompress the data:
-	char Uncompressed[CHUNK_INFLATE_MAX];
-	z_stream strm;
-	strm.zalloc = (alloc_func)NULL;
-	strm.zfree = (free_func)NULL;
-	strm.opaque = NULL;
-	inflateInit(&strm);
-	strm.next_out  = (Bytef *)Uncompressed;
-	strm.avail_out = sizeof(Uncompressed);
-	strm.next_in   = (Bytef *)a_Data.data();
-	strm.avail_in  = (uInt)a_Data.size();
-	int res = inflate(&strm, Z_FINISH);
-	inflateEnd(&strm);
-	if (res != Z_STREAM_END)
+	// Uncompress the data:
+	AString Uncompressed;
+	int res = InflateString(a_Data.data(), a_Data.size(), Uncompressed);
+	if (res != Z_OK)
 	{
+		LOGWARNING("Uncompressing chunk [%d, %d] failed: %d", a_Chunk.m_ChunkX, a_Chunk.m_ChunkZ, res);
+		LOAD_FAILED(a_Chunk.m_ChunkX, a_Chunk.m_ChunkZ);
 		return false;
 	}
 	
 	// Parse the NBT data:
-	cParsedNBT NBT(Uncompressed, strm.total_out);
+	cParsedNBT NBT(Uncompressed.data(), Uncompressed.size());
 	if (!NBT.IsValid())
 	{
 		// NBT Parsing failed
+		LOAD_FAILED(a_Chunk.m_ChunkX, a_Chunk.m_ChunkZ);
 		return false;
 	}
 
@@ -317,11 +319,19 @@ bool cWSSAnvil::LoadChunkFromNBT(const cChunkCoords & a_Chunk, const cParsedNBT
 	int Level = a_NBT.FindChildByName(0, "Level");
 	if (Level < 0)
 	{
+		LOAD_FAILED(a_Chunk.m_ChunkX, a_Chunk.m_ChunkZ);
 		return false;
 	}
 	int Sections = a_NBT.FindChildByName(Level, "Sections");
-	if ((Sections < 0) || (a_NBT.GetType(Sections) != TAG_List) || (a_NBT.GetChildrenType(Sections) != TAG_Compound))
+	if ((Sections < 0) || (a_NBT.GetType(Sections) != TAG_List))
+	{
+		LOAD_FAILED(a_Chunk.m_ChunkX, a_Chunk.m_ChunkZ);
+		return false;
+	}
+	eTagType SectionsType = a_NBT.GetChildrenType(Sections);
+	if ((SectionsType != TAG_Compound) && (SectionsType != TAG_End))
 	{
+		LOAD_FAILED(a_Chunk.m_ChunkX, a_Chunk.m_ChunkZ);
 		return false;
 	}
 	for (int Child = a_NBT.GetFirstChild(Sections); Child >= 0; Child = a_NBT.GetNextSibling(Child))
@@ -585,7 +595,7 @@ void cWSSAnvil::LoadBlockEntitiesFromNBT(cBlockEntityList & a_BlockEntities, con
 
 		// Get the BlockEntity's position
 		int x, y, z;
-		if (!GetBlockEntityNBTPos(a_NBT, Child, x, y, z))
+		if (!GetBlockEntityNBTPos(a_NBT, Child, x, y, z) || (y < 0) || (y >= cChunkDef::Height))
 		{
 			LOGWARNING("Bad block entity, missing the coords. Will be ignored.");
 			continue;
@@ -613,6 +623,8 @@ void cWSSAnvil::LoadBlockEntitiesFromNBT(cBlockEntityList & a_BlockEntities, con
 
 cBlockEntity * cWSSAnvil::LoadBlockEntityFromNBT(const cParsedNBT & a_NBT, int a_Tag, int a_BlockX, int a_BlockY, int a_BlockZ, BLOCKTYPE a_BlockType, NIBBLETYPE a_BlockMeta)
 {
+	ASSERT((a_BlockY >= 0) && (a_BlockY < cChunkDef::Height));
+
 	// Load the specific BlockEntity type:
 	switch (a_BlockType)
 	{
@@ -2824,30 +2836,42 @@ bool cWSSAnvil::cMCAFile::GetChunkData(const cChunkCoords & a_Chunk, AString & a
 	}
 	unsigned ChunkLocation = ntohl(m_Header[LocalX + 32 * LocalZ]);
 	unsigned ChunkOffset = ChunkLocation >> 8;
+	if (ChunkOffset < 2)
+	{
+		return false;
+	}
 	
 	m_File.Seek((int)ChunkOffset * 4096);
 	
 	int ChunkSize = 0;
 	if (m_File.Read(&ChunkSize, 4) != 4)
 	{
+		LOAD_FAILED(a_Chunk.m_ChunkX, a_Chunk.m_ChunkZ);
 		return false;
 	}
 	ChunkSize = ntohl((u_long)ChunkSize);
 	char CompressionType = 0;
 	if (m_File.Read(&CompressionType, 1) != 1)
 	{
+		LOAD_FAILED(a_Chunk.m_ChunkX, a_Chunk.m_ChunkZ);
 		return false;
 	}
 	if (CompressionType != 2)
 	{
 		// Chunk is in an unknown compression
+		LOAD_FAILED(a_Chunk.m_ChunkX, a_Chunk.m_ChunkZ);
 		return false;
 	}
 	ChunkSize--;
 	
 	// HACK: This depends on the internal knowledge that AString's data() function returns the internal buffer directly
 	a_Data.assign(ChunkSize, '\0');
-	return (m_File.Read((void *)a_Data.data(), ChunkSize) == ChunkSize);
+	if (m_File.Read((void *)a_Data.data(), ChunkSize) == ChunkSize)
+	{
+		return true;
+	}
+	LOAD_FAILED(a_Chunk.m_ChunkX, a_Chunk.m_ChunkZ);
+	return false;
 }
 
 
@@ -2902,7 +2926,13 @@ bool cWSSAnvil::cMCAFile::SetChunkData(const cChunkCoords & a_Chunk, const AStri
 	
 	// Store the header:
 	ChunkSize = ((u_long)a_Data.size() + MCA_CHUNK_HEADER_LENGTH + 4095) / 4096;  // Round data size *up* to nearest 4KB sector, make it a sector number
-	ASSERT(ChunkSize < 256);
+	if (ChunkSize > 255)
+	{
+		LOGWARNING("Cannot save chunk [%d, %d], the data is too large (%u KiB, maximum is 1024 KiB). Remove some entities and retry.",
+			a_Chunk.m_ChunkX, a_Chunk.m_ChunkZ, (unsigned)(ChunkSize * 4)
+		);
+		return false;
+	}
 	m_Header[LocalX + 32 * LocalZ] = htonl((ChunkSector << 8) | ChunkSize);
 	if (m_File.Seek(0) < 0)
 	{