check secret target is an absolute windows path

pkg/compose/create.go

@@ -863,7 +863,7 @@
 		target := config.Target
 		if config.Target == "" {
 			target = configsBaseDir + config.Source
-		} else if !isUnixAbs(config.Target) {
+		} else if !isAbsTarget(config.Target) {
 			target = configsBaseDir + config.Target
 		}
 
@@ -898,7 +898,7 @@
 		target := secret.Target
 		if secret.Target == "" {
 			target = secretsDir + secret.Source
-		} else if !isUnixAbs(secret.Target) {
+		} else if !isAbsTarget(secret.Target) {
 			target = secretsDir + secret.Target
 		}
 
@@ -929,10 +929,24 @@
 	return values, nil
 }
 
+func isAbsTarget(p string) bool {
+	return isUnixAbs(p) || isWindowsAbs(p)
+}
+
 func isUnixAbs(p string) bool {
 	return strings.HasPrefix(p, "/")
 }
 
+func isWindowsAbs(p string) bool {
+	if strings.HasPrefix(p, "\\\\") {
+		return true
+	}
+	if len(p) > 2 && p[1] == ':' {
+		return p[2] == '\\'
+	}
+	return false
+}
+
 func buildMount(project types.Project, volume types.ServiceVolumeConfig) (mount.Mount, error) {
 	source := volume.Source
 	// on windows, filepath.IsAbs(source) is false for unix style abs path like /var/run/docker.sock.

pkg/compose/secrets.go

@@ -66,7 +66,7 @@ func createTar(env string, config types.ServiceSecretConfig) (bytes.Buffer, erro
 	target := config.Target
 	if config.Target == "" {
 		target = "/run/secrets/" + config.Source
-	} else if !isUnixAbs(config.Target) {
+	} else if !isAbsTarget(config.Target) {
 		target = "/run/secrets/" + config.Target
 	}