From 713db5e37de5110bf83d963dc7306b37c00a0e6c Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?nils=20m=C3=A5s=C3=A9n?= <nils@piksel.se>
Date: Thu, 28 Apr 2022 12:24:32 +0200
Subject: [PATCH] fix(zip): 0 in zip64 local sizes using descriptors

---
 src/ICSharpCode.SharpZipLib/Zip/ZipFile.cs   | 4 ++--
 src/ICSharpCode.SharpZipLib/Zip/ZipFormat.cs | 5 +++--
 2 files changed, 5 insertions(+), 4 deletions(-)

diff --git a/src/ICSharpCode.SharpZipLib/Zip/ZipFile.cs b/src/ICSharpCode.SharpZipLib/Zip/ZipFile.cs
index 1e9bf43d3..b34b7bec5 100644
--- a/src/ICSharpCode.SharpZipLib/Zip/ZipFile.cs
+++ b/src/ICSharpCode.SharpZipLib/Zip/ZipFile.cs
@@ -1145,12 +1145,12 @@ private long TestLocalHeader(ZipEntry entry, HeaderTest tests)
 					if (localFlags.HasAny(GeneralBitFlags.Descriptor))
 					{
 						// These may be valid if patched later
-						if ((size > 0) && (size != entry.Size))
+						if ((size != 0) && (size != entry.Size))
 						{
 							throw new ZipException("Size invalid for descriptor");
 						}
 
-						if ((compressedSize > 0) && (compressedSize != entry.CompressedSize))
+						if ((compressedSize != 0) && (compressedSize != entry.CompressedSize))
 						{
 							throw new ZipException("Compressed size invalid for descriptor");
 						}
diff --git a/src/ICSharpCode.SharpZipLib/Zip/ZipFormat.cs b/src/ICSharpCode.SharpZipLib/Zip/ZipFormat.cs
index a37ab3031..cf78ef54f 100644
--- a/src/ICSharpCode.SharpZipLib/Zip/ZipFormat.cs
+++ b/src/ICSharpCode.SharpZipLib/Zip/ZipFormat.cs
@@ -114,8 +114,9 @@ internal static int WriteLocalHeader(Stream stream, ZipEntry entry, out EntryPat
 				}
 				else
 				{
-					ed.AddLeLong(-1);
-					ed.AddLeLong(-1);
+					// If the sizes are stored in the descriptor, the local Zip64 sizes should be 0
+					ed.AddLeLong(0);
+					ed.AddLeLong(0);
 				}
 				ed.AddNewEntry(1);