migrated to external IP allocator

pkg/haproxy/haproxy.go

@@ -10,9 +10,12 @@ import (
 	"os"
 	"os/exec"
 	"sync"
+	"syscall"
 	"text/template"
 )
 
+const Nobody = 65534
+
 type ServiceManager interface {
 	Reload(context.Context) error
 	Status(context.Context) error
@@ -21,6 +24,7 @@ type ServiceManager interface {
 }
 
 type HAProxyManager struct {
+	// protects config update
 	sync.Mutex
 
 	configFile string
@@ -57,7 +61,24 @@ func (ha *HAProxyManager) checkConfig(ctx context.Context, lbs Config) (hash []b
 		return
 	}
 	hash = h.Sum(nil)
-	out, err := exec.CommandContext(ctx, "haproxy", "-c", "-f", tmp.Name()).CombinedOutput()
+	err = os.Chmod(tmp.Name(), 0640)
+	if err != nil {
+		return
+	}
+	err = os.Chown(tmp.Name(), -1, Nobody)
+	if err != nil {
+		return
+	}
+	cmd := exec.CommandContext(ctx, "haproxy", "-c", "-f", tmp.Name())
+	cmd.Dir = os.TempDir()
+	cmd.SysProcAttr = &syscall.SysProcAttr{
+		Credential: &syscall.Credential{
+			Uid: Nobody,
+			Gid: Nobody,
+		},
+		Setsid: true,
+	}
+	out, err := cmd.CombinedOutput()
 	if err != nil {
 		err = fmt.Errorf("%s:%w", string(out), err)
 	}