From 5203c9d44110a194b67f1e7f5dccdb7733ba66f9 Mon Sep 17 00:00:00 2001
From: Wesley Shillingford <wezrule@hotmail.com>
Date: Fri, 3 Apr 2020 11:27:46 +0100
Subject: [PATCH] [TSAN] start_time data race in bootstrap_client

---
 nano/node/bootstrap/bootstrap_bulk_pull.cpp   |  2 +-
 nano/node/bootstrap/bootstrap_connections.cpp | 11 +++++++++--
 nano/node/bootstrap/bootstrap_connections.hpp |  6 +++++-
 3 files changed, 15 insertions(+), 4 deletions(-)

diff --git a/nano/node/bootstrap/bootstrap_bulk_pull.cpp b/nano/node/bootstrap/bootstrap_bulk_pull.cpp
index fc050471a3..99a6c77357 100644
--- a/nano/node/bootstrap/bootstrap_bulk_pull.cpp
+++ b/nano/node/bootstrap/bootstrap_bulk_pull.cpp
@@ -241,7 +241,7 @@ void nano::bulk_pull_client::received_block (boost::system::error_code const & e
 			}
 			if (connection->block_count++ == 0)
 			{
-				connection->start_time = std::chrono::steady_clock::now ();
+				connection->set_start_time (std::chrono::steady_clock::now ());
 			}
 			attempt->total_blocks++;
 			bool stop_pull (attempt->process_block (block, known_account, pull_blocks, pull.count, block_expected, pull.retry_limit));
diff --git a/nano/node/bootstrap/bootstrap_connections.cpp b/nano/node/bootstrap/bootstrap_connections.cpp
index 30cccef0a3..bf412f21b2 100644
--- a/nano/node/bootstrap/bootstrap_connections.cpp
+++ b/nano/node/bootstrap/bootstrap_connections.cpp
@@ -19,7 +19,7 @@ connections (connections_a),
 channel (channel_a),
 socket (socket_a),
 receive_buffer (std::make_shared<std::vector<uint8_t>> ()),
-start_time (std::chrono::steady_clock::now ())
+start_time_m (std::chrono::steady_clock::now ())
 {
 	++connections->connections_count;
 	receive_buffer->resize (256);
@@ -36,9 +36,16 @@ double nano::bootstrap_client::block_rate () const
 	return static_cast<double> (block_count.load () / elapsed);
 }
 
+void nano::bootstrap_client::set_start_time (std::chrono::steady_clock::time_point start_time_a)
+{
+	nano::lock_guard<std::mutex> guard (start_time_mutex);
+	start_time_m = start_time_a;
+}
+
 double nano::bootstrap_client::elapsed_seconds () const
 {
-	return std::chrono::duration_cast<std::chrono::duration<double>> (std::chrono::steady_clock::now () - start_time).count ();
+	nano::lock_guard<std::mutex> guard (start_time_mutex);
+	return std::chrono::duration_cast<std::chrono::duration<double>> (std::chrono::steady_clock::now () - start_time_m).count ();
 }
 
 void nano::bootstrap_client::stop (bool force)
diff --git a/nano/node/bootstrap/bootstrap_connections.hpp b/nano/node/bootstrap/bootstrap_connections.hpp
index 652e20133f..85ef479a1f 100644
--- a/nano/node/bootstrap/bootstrap_connections.hpp
+++ b/nano/node/bootstrap/bootstrap_connections.hpp
@@ -26,15 +26,19 @@ class bootstrap_client final : public std::enable_shared_from_this<bootstrap_cli
 	void stop (bool force);
 	double block_rate () const;
 	double elapsed_seconds () const;
+	void set_start_time (std::chrono::steady_clock::time_point start_time_a);
 	std::shared_ptr<nano::node> node;
 	std::shared_ptr<nano::bootstrap_connections> connections;
 	std::shared_ptr<nano::transport::channel_tcp> channel;
 	std::shared_ptr<nano::socket> socket;
 	std::shared_ptr<std::vector<uint8_t>> receive_buffer;
-	std::chrono::steady_clock::time_point start_time;
 	std::atomic<uint64_t> block_count{ 0 };
 	std::atomic<bool> pending_stop{ false };
 	std::atomic<bool> hard_stop{ false };
+
+private:
+	mutable std::mutex start_time_mutex;
+	std::chrono::steady_clock::time_point start_time_m;
 };
 
 class bootstrap_connections final : public std::enable_shared_from_this<bootstrap_connections>