From 8a1bbf1345c9ea9a83c99d120dc462bd612fb4df Mon Sep 17 00:00:00 2001
From: "Rodrigo Q. Saramago" <rodrigoqsaramago@gmail.com>
Date: Tue, 6 Dec 2022 13:43:52 +0100
Subject: [PATCH] Enforce non-empty data section

---
 libevmasm/Assembly.cpp | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/libevmasm/Assembly.cpp b/libevmasm/Assembly.cpp
index df289c20d..7c2752af4 100644
--- a/libevmasm/Assembly.cpp
+++ b/libevmasm/Assembly.cpp
@@ -774,10 +774,15 @@ LinkerObject const& Assembly::assemble() const
 		toBigEndian(ret.bytecode.size(), r);
 	}
 
-	auto const dataLength = ret.bytecode.size() - dataStart;
+	auto dataLength = ret.bytecode.size() - dataStart;
 	if (m_eofVersion.has_value())
 	{
-		assertThrow(/*dataLength >= 0 && */ dataLength <= 0xffff, AssemblyException, "Invalid data section size.");
+		if (dataLength == 0)
+		{
+			ret.bytecode.push_back(0);
+			dataLength++;
+		}
+		assertThrow(dataLength > 0u && dataLength <= 0xffff, AssemblyException, "Invalid data section size.");
 		toBigEndian(dataLength, eofDataLength);
 	}