What's the best way to work for a supervisor who feels unsecured?

If your work performance is good but the supervisor that you report to directly feels threatened that you would eventually go above and beyond them, so the supervisor often back-stabs and undermines you when reporting to her boss. What would be the best way to handle it and let the supervisor's boss realize that you were undermined since it would be cutthroat if the supervisor finds out that you go directly to her boss? Please advise. Thank you.