Make it thread safe

Signed-off-by: Kimmo Lehto <[email protected]>

version.go

@@ -7,6 +7,7 @@ import (
 	"sort"
 	"strconv"
 	"strings"
+	"sync"
 
 	goversion "github.com/hashicorp/go-version"
 )
@@ -17,6 +18,7 @@ var BaseUrl = "https://github.com/k0sproject/k0s/"
 type Version struct {
 	goversion.Version
 	buf *bytes.Buffer
+	mu  *sync.Mutex
 }
 
 func pair(a, b *Version) Collection {
@@ -29,6 +31,9 @@ func (v *Version) String() string {
 		return ""
 	}
 
+	v.mu.Lock()
+	defer v.mu.Unlock()
+
 	if v.buf != nil {
 		return v.buf.String()
 	}
@@ -180,6 +185,7 @@ func (v *Version) unmarshal(f func(interface{}) error) error {
 		return fmt.Errorf("failed to unmarshal version: %w", err)
 	}
 	*v = *newV
+	v.mu = new(sync.Mutex)
 	return nil
 }
 
@@ -218,7 +224,7 @@ func NewVersion(v string) (*Version, error) {
 		return nil, err
 	}
 
-	return &Version{Version: *n}, nil
+	return &Version{Version: *n, mu: new(sync.Mutex)}, nil
 }
 
 // MustParse is like NewVersion but panics if the version cannot be parsed.