Disable Exec on non-linux platforms

CHANGELOG.md

@@ -51,6 +51,7 @@ BUG FIXES:
    Consul agent [GH-4365]
  * driver/docker: Fix docker credential helper support [[GH-4266](https://github.com/hashicorp/nomad/issues/4266)]
  * driver/docker: Fix panic when docker client configuration options are invalid [[GH-4303](https://github.com/hashicorp/nomad/issues/4303)]
+ * driver/exec: Disable exec on non-linux platforms [GH-4366]
  * rpc: Fix RPC tunneling when running both client/server on one machine [[GH-4317](https://github.com/hashicorp/nomad/issues/4317)]
  * ui: Track the method in XHR tracking to prevent errant ACL error dialogs when stopping a job [[GH-4319](https://github.com/hashicorp/nomad/issues/4319)]
  * ui: Use Polling instead of Streaming for logs in Safari [[GH-4335](https://github.com/hashicorp/nomad/issues/4335)]

client/driver/exec_default.go

@@ -9,6 +9,6 @@ import (
 
 func (d *ExecDriver) Fingerprint(req *cstructs.FingerprintRequest, resp *cstructs.FingerprintResponse) error {
 	d.fingerprintSuccess = helper.BoolToPtr(false)
-	resp.Detected = true
+	resp.Detected = false
 	return nil
 }

client/driver/exec_test.go

@@ -7,6 +7,7 @@ import (
 	"io/ioutil"
 	"path/filepath"
 	"reflect"
+	"runtime"
 	"strings"
 	"testing"
 	"time"
@@ -20,6 +21,30 @@ import (
 	ctestutils "github.com/hashicorp/nomad/client/testutil"
 )
 
+// Test that we do not enable exec on non-linux machines
+func TestExecDriver_Fingerprint_NonLinux(t *testing.T) {
+	if !testutil.IsTravis() {
+		t.Parallel()
+	}
+	if runtime.GOOS == "linux" {
+		t.Skip("Test only available not on Linux")
+	}
+
+	d := NewExecDriver(&DriverContext{})
+	node := &structs.Node{}
+
+	request := &cstructs.FingerprintRequest{Config: &config.Config{}, Node: node}
+	var response cstructs.FingerprintResponse
+	err := d.Fingerprint(request, &response)
+	if err != nil {
+		t.Fatalf("err: %v", err)
+	}
+
+	if response.Detected {
+		t.Fatalf("Should not be detected on non-linux platforms")
+	}
+}
+
 func TestExecDriver_Fingerprint(t *testing.T) {
 	if !testutil.IsTravis() {
 		t.Parallel()