From 97725cd6ff05d3ce91187382bac82847e6c7f923 Mon Sep 17 00:00:00 2001
From: Brian Goff <cpuguy83@gmail.com>
Date: Wed, 16 Aug 2017 09:27:49 -0400
Subject: [PATCH] Lock goroutine to OS thread while changing NS

Prevents an issue where the goroutine may jump to a new OS thread during
execution putting it into a mount/network NS that is unexpected.

Signed-off-by: Brian Goff <cpuguy83@gmail.com>
(cherry picked from commit 65bb58fad9f75b4302a972663a238e3f1a7ba3bb)
Signed-off-by: Brian Goff <cpuguy83@gmail.com>
---
 drivers/overlay/ov_network.go | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/drivers/overlay/ov_network.go b/drivers/overlay/ov_network.go
index 6dd0ec9d6e..126093fefe 100644
--- a/drivers/overlay/ov_network.go
+++ b/drivers/overlay/ov_network.go
@@ -8,6 +8,7 @@ import (
 	"os"
 	"os/exec"
 	"path/filepath"
+	"runtime"
 	"strconv"
 	"strings"
 	"sync"
@@ -81,6 +82,10 @@ func setDefaultVlan() {
 		logrus.Error("insufficient number of arguments")
 		os.Exit(1)
 	}
+
+	runtime.LockOSThread()
+	defer runtime.UnlockOSThread()
+
 	nsPath := os.Args[1]
 	ns, err := netns.GetFromPath(nsPath)
 	if err != nil {