From 085babd1ea1f4252c9a35f8375c6ecc86f55ce01 Mon Sep 17 00:00:00 2001
From: orignal <i2porignal@yandex.ru>
Date: Thu, 26 Feb 2026 15:38:45 -0500
Subject: [PATCH] avoid possible double termination. Use atomic swap

---
 libi2pd/NTCP2.cpp | 4 ++--
 libi2pd/NTCP2.h   | 3 ++-
 2 files changed, 4 insertions(+), 3 deletions(-)

diff --git a/libi2pd/NTCP2.cpp b/libi2pd/NTCP2.cpp
index 9efd8fec..d74c2525 100644
--- a/libi2pd/NTCP2.cpp
+++ b/libi2pd/NTCP2.cpp
@@ -563,9 +563,9 @@ namespace transport
 
 	void NTCP2Session::Terminate ()
 	{
-		if (!m_IsTerminated)
+		bool isTerminated = m_IsTerminated.exchange (true);
+		if (!isTerminated)
 		{
-			m_IsTerminated = true;
 			m_IsEstablished = false;
 			boost::system::error_code ec;
 			m_Socket.shutdown(boost::asio::ip::tcp::socket::shutdown_both, ec);
diff --git a/libi2pd/NTCP2.h b/libi2pd/NTCP2.h
index 40a2b21f..55d40ed3 100644
--- a/libi2pd/NTCP2.h
+++ b/libi2pd/NTCP2.h
@@ -15,6 +15,7 @@
 #include <map>
 #include <array>
 #include <random>
+#include <atomic>
 #include <openssl/bn.h>
 #include <openssl/evp.h>
 #include <boost/asio.hpp>
@@ -222,7 +223,7 @@ namespace transport
 			NTCP2Server& m_Server;
 			boost::asio::ip::tcp::socket m_Socket;
 			boost::asio::ip::tcp::endpoint m_RemoteEndpoint;
-			bool m_IsEstablished, m_IsTerminated;
+			std::atomic<bool> m_IsEstablished, m_IsTerminated;
 
 			std::unique_ptr<NTCP2Establisher> m_Establisher;
 			// data phase