iterate chunks crash fix (#376)

* Bugfix: Add explicit lambda capture in CasContainer::IterateChunks to avoid accessing state data references

1 files changed, 21 insertions, 10 deletions

diff --git a/src/zenstore/blockstore.cpp b/src/zenstore/blockstore.cpp
index 7cc09be15..c58080e6a 100644
--- a/src/zenstore/blockstore.cpp
+++ b/src/zenstore/blockstore.cpp
@@ -735,6 +735,8 @@ BlockStore::IterateBlock(std::span<const BlockStoreLocation>   ChunkLocations,
 		return true;
 	}
 
+	ZEN_ASSERT(ChunkLocations.size() >= InChunkIndexes.size());
+
 	if (LargeSizeLimit == 0)
 	{
 		LargeSizeLimit = DefaultIterateSmallChunkWindowSize;
@@ -746,7 +748,10 @@ BlockStore::IterateBlock(std::span<const BlockStoreLocation>   ChunkLocations,
 
 	IterateSmallChunkWindowSize = Min((LargeSizeLimit + IterateSmallChunkMaxGapSize) * ChunkLocations.size(), IterateSmallChunkWindowSize);
 
-	uint32_t			BlockIndex = ChunkLocations[InChunkIndexes[0]].BlockIndex;
+	const size_t FirstLocationIndex = InChunkIndexes[0];
+	ZEN_ASSERT(FirstLocationIndex < ChunkLocations.size());
+
+	const uint32_t		BlockIndex = ChunkLocations[FirstLocationIndex].BlockIndex;
 	std::vector<size_t> ChunkIndexes(InChunkIndexes.begin(), InChunkIndexes.end());
 	std::sort(ChunkIndexes.begin(), ChunkIndexes.end(), [&](size_t IndexA, size_t IndexB) -> bool {
 		return ChunkLocations[IndexA].Offset < ChunkLocations[IndexB].Offset;
@@ -756,8 +761,9 @@ BlockStore::IterateBlock(std::span<const BlockStoreLocation>   ChunkLocations,
 						 IterateSmallChunkWindowSize,
 						 IterateSmallChunkMaxGapSize,
 						 &ChunkLocations](uint64_t BlockFileSize, std::span<const size_t> ChunkIndexes, size_t StartIndexOffset) -> size_t {
-		size_t					  ChunkCount	= 0;
-		size_t					  StartIndex	= ChunkIndexes[StartIndexOffset];
+		size_t ChunkCount = 0;
+		size_t StartIndex = ChunkIndexes[StartIndexOffset];
+		ZEN_ASSERT(StartIndex < ChunkLocations.size());
 		const BlockStoreLocation& StartLocation = ChunkLocations[StartIndex];
 		uint64_t				  StartOffset	= StartLocation.Offset;
 		uint64_t				  LastEnd		= StartOffset + StartLocation.Size;
@@ -810,22 +816,26 @@ BlockStore::IterateBlock(std::span<const BlockStoreLocation>   ChunkLocations,
 		ZEN_ASSERT(BlockFile);
 		InsertLock.ReleaseNow();
 
+		const size_t BlockSize = BlockFile->FileSize();
+
 		IoBuffer ReadBuffer;
 		void*	 BufferBase = nullptr;
 
 		size_t LocationIndexOffset = 0;
 		while (LocationIndexOffset < ChunkIndexes.size())
 		{
-			size_t					  ChunkIndex	= ChunkIndexes[LocationIndexOffset];
+			size_t ChunkIndex = ChunkIndexes[LocationIndexOffset];
+			ZEN_ASSERT(ChunkIndex < ChunkLocations.size());
 			const BlockStoreLocation& FirstLocation = ChunkLocations[ChunkIndex];
+			ZEN_ASSERT(FirstLocation.BlockIndex == BlockIndex);
 
-			const size_t BlockSize	= BlockFile->FileSize();
 			const size_t RangeCount = GetNextRange(BlockSize, ChunkIndexes, LocationIndexOffset);
 			if (RangeCount > 1)
 			{
-				size_t					  LastChunkIndex = ChunkIndexes[LocationIndexOffset + RangeCount - 1];
-				const BlockStoreLocation& LastLocation	 = ChunkLocations[LastChunkIndex];
-				uint64_t				  Size			 = LastLocation.Offset + LastLocation.Size - FirstLocation.Offset;
+				size_t LastChunkIndex = ChunkIndexes[LocationIndexOffset + RangeCount - 1];
+				ZEN_ASSERT(LastChunkIndex < ChunkLocations.size());
+				const BlockStoreLocation& LastLocation = ChunkLocations[LastChunkIndex];
+				uint64_t				  Size		   = LastLocation.Offset + LastLocation.Size - FirstLocation.Offset;
 				if (ReadBuffer.GetSize() < Size)
 				{
 					ReadBuffer = IoBuffer(Min(Size * 2, IterateSmallChunkWindowSize));
@@ -834,8 +844,9 @@ BlockStore::IterateBlock(std::span<const BlockStoreLocation>   ChunkLocations,
 				BlockFile->Read(BufferBase, Size, FirstLocation.Offset);
 				for (size_t RangeIndex = 0; RangeIndex < RangeCount; ++RangeIndex)
 				{
-					size_t					  NextChunkIndex = ChunkIndexes[LocationIndexOffset + RangeIndex];
-					const BlockStoreLocation& ChunkLocation	 = ChunkLocations[NextChunkIndex];
+					size_t NextChunkIndex = ChunkIndexes[LocationIndexOffset + RangeIndex];
+					ZEN_ASSERT(NextChunkIndex < ChunkLocations.size());
+					const BlockStoreLocation& ChunkLocation = ChunkLocations[NextChunkIndex];
 					if (ChunkLocation.Size == 0 || ((ChunkLocation.Offset + ChunkLocation.Size) > BlockSize))
 					{
 						ZEN_LOG_SCOPE("chunk [{},{}] out of bounds (block #{} file size = {})",