From b5ad9fb4c7475b4f4516bf401a7bb2cc2f20b3ee Mon Sep 17 00:00:00 2001 From: Dan Engelbrecht Date: Wed, 26 Nov 2025 13:04:38 +0100 Subject: RawOffset can be anything and we expect an empty buffer to be returned along with RawSize = 0 if the offset was out of bounds for the value. (#666) --- src/zencore/compress.cpp | 23 +++++++++++++++++++---- 1 file changed, 19 insertions(+), 4 deletions(-) (limited to 'src/zencore/compress.cpp') diff --git a/src/zencore/compress.cpp b/src/zencore/compress.cpp index d9f381811..84af83119 100644 --- a/src/zencore/compress.cpp +++ b/src/zencore/compress.cpp @@ -1995,8 +1995,15 @@ CompressedBuffer::CopyRange(uint64_t RawOffset, uint64_t RawSize) const UniqueBuffer RawHeaderData; if (ReadHeader(CompressedData, Header, &RawHeaderData)) { - const uint64_t TotalRawSize = RawSize < ~uint64_t(0) ? RawSize : Header.TotalRawSize - RawOffset; - Range.CompressedData = CopyCompressedRange(Header, RawHeaderData.GetView(), CompressedData, RawOffset, TotalRawSize); + if (RawOffset < Header.TotalRawSize) + { + const uint64_t MaxRawSize = RawOffset == ~uint64_t(0) ? Header.TotalRawSize : Header.TotalRawSize - RawOffset; + const uint64_t TotalRawSize = RawSize == ~uint64_t(0) ? MaxRawSize : Min(RawSize, MaxRawSize); + if (TotalRawSize > 0) + { + Range.CompressedData = CopyCompressedRange(Header, RawHeaderData.GetView(), CompressedData, RawOffset, TotalRawSize); + } + } } } return Range; @@ -2012,8 +2019,16 @@ CompressedBuffer::GetRange(uint64_t RawOffset, uint64_t RawSize) const UniqueBuffer RawHeaderData; if (ReadHeader(CompressedData, Header, &RawHeaderData)) { - const uint64_t TotalRawSize = RawSize < ~uint64_t(0) ? RawSize : Header.TotalRawSize - RawOffset; - Range.CompressedData = GetCompressedRange(Header, RawHeaderData.GetView(), CompressedData, RawOffset, TotalRawSize); + if (RawOffset < Header.TotalRawSize) + { + const uint64_t MaxRawSize = RawOffset == ~uint64_t(0) ? Header.TotalRawSize : Header.TotalRawSize - RawOffset; + const uint64_t TotalRawSize = RawSize == ~uint64_t(0) ? MaxRawSize : Min(RawSize, MaxRawSize); + + if (TotalRawSize > 0) + { + Range.CompressedData = GetCompressedRange(Header, RawHeaderData.GetView(), CompressedData, RawOffset, TotalRawSize); + } + } } } return Range; -- cgit v1.2.3