diff --git a/lib/digsig.c b/lib/digsig.c
index 03d7c63837aecb36f74037212e9e7dd421e2e4c9..6ba6fcd92dd10cd2c78898b35c65a0540b19bfb3 100644
--- a/lib/digsig.c
+++ b/lib/digsig.c
@@ -87,6 +87,12 @@ static int digsig_verify_rsa(struct key *key,
 	down_read(&key->sem);
 	ukp = user_key_payload_locked(key);
 
+	if (!ukp) {
+		/* key was revoked before we acquired its semaphore */
+		err = -EKEYREVOKED;
+		goto err1;
+	}
+
 	if (ukp->datalen < sizeof(*pkh))
 		goto err1;