Check LH offset when writing LH. Fix dotnet#94899

ZipArchiveEntry didn't set ZIP64 in local headers for small files if their offset are >4GB.
carlossanlop · May 9, 2024 · dc589e5 · dc589e5
1 parent 7037516
commit dc589e5
Showing 1 changed file with 1 addition and 1 deletion.
diff --git a/src/libraries/System.IO.Compression/src/System/IO/Compression/ZipArchiveEntry.cs b/src/libraries/System.IO.Compression/src/System/IO/Compression/ZipArchiveEntry.cs
@@ -964,7 +964,7 @@ private void WriteCrcAndSizesInLocalHeader(bool zip64HeaderUsed)
             long finalPosition = _archive.ArchiveStream.Position;
             BinaryWriter writer = new BinaryWriter(_archive.ArchiveStream);
 
-            bool zip64Needed = SizesTooLarge()
+            bool zip64Needed = SizesTooLarge() || (_offsetOfLocalHeader > uint.MaxValue)
 #if DEBUG_FORCE_ZIP64
                 || _archive._forceZip64
 #endif