From b486354a9cd4e2d2c646ede02dc24147dfe4643d Mon Sep 17 00:00:00 2001
From: Mitchell Hashimoto <mitchell.hashimoto@gmail.com>
Date: Mon, 26 Dec 2016 16:29:32 -0800
Subject: [PATCH] communicator/ssh: Disconnect() should also kill the actual
 connection

---
 communicator/ssh/communicator.go | 19 ++++++++++++++++++-
 1 file changed, 18 insertions(+), 1 deletion(-)

diff --git a/communicator/ssh/communicator.go b/communicator/ssh/communicator.go
index 32a881c04..36b698a9a 100644
--- a/communicator/ssh/communicator.go
+++ b/communicator/ssh/communicator.go
@@ -42,6 +42,8 @@ type Communicator struct {
 	config   *sshConfig
 	conn     net.Conn
 	address  string
+
+	lock sync.Mutex
 }
 
 type sshConfig struct {
@@ -96,6 +98,10 @@ func New(s *terraform.InstanceState) (*Communicator, error) {
 
 // Connect implementation of communicator.Communicator interface
 func (c *Communicator) Connect(o terraform.UIOutput) (err error) {
+	// Grab a lock so we can modify our internal attributes
+	c.lock.Lock()
+	defer c.lock.Unlock()
+
 	if c.conn != nil {
 		c.conn.Close()
 	}
@@ -190,8 +196,19 @@ func (c *Communicator) Connect(o terraform.UIOutput) (err error) {
 
 // Disconnect implementation of communicator.Communicator interface
 func (c *Communicator) Disconnect() error {
+	c.lock.Lock()
+	defer c.lock.Unlock()
+
 	if c.config.sshAgent != nil {
-		return c.config.sshAgent.Close()
+		if err := c.config.sshAgent.Close(); err != nil {
+			return err
+		}
+	}
+
+	if c.conn != nil {
+		conn := c.conn
+		c.conn = nil
+		return conn.Close()
 	}
 
 	return nil