Merge pull request #8335 from sakshamkhanna/bugfix/sakshamkhanna/ssh_runner_race_condition

added mutex lock over teePrefix()

pkg/minikube/command/command_runner.go

@@ -25,6 +25,7 @@ import (
 	"os/exec"
 	"strconv"
 	"strings"
+	"sync"
 	"time"
 
 	"github.com/pkg/errors"
@@ -37,6 +38,9 @@ var (
 
 	// OutPrefix notes output
 	OutPrefix = "> "
+
+	// Mutex protects teePrefix from writing to same log buffer parallelly
+	logMutex = &sync.Mutex{}
 )
 
 // RunResult holds the results of a Runner
@@ -88,6 +92,9 @@ func (rr RunResult) Output() string {
 
 // teePrefix copies bytes from a reader to writer, logging each new line.
 func teePrefix(prefix string, r io.Reader, w io.Writer, logger func(format string, args ...interface{})) error {
+	logMutex.Lock()
+	defer logMutex.Unlock()
+
 	scanner := bufio.NewScanner(r)
 	scanner.Split(bufio.ScanBytes)
 	var line bytes.Buffer