SAE: Fix memory leak in random number generation

If the randomly generated bignum does not meet the validation steps, the
iteration loop in sae_get_rand() did not free the data properly. Fix the
memory leak by freeing the temporary bignum before starting the next
attempt at generating the value.

Signed-off-by: Jouni Malinen <j@w1.fi>

src/common/sae.c

@@ -134,8 +134,10 @@ static struct crypto_bignum * sae_get_rand(struct sae_data *sae)
 			return NULL;
 		if (crypto_bignum_is_zero(bn) ||
 		    crypto_bignum_is_one(bn) ||
-		    crypto_bignum_cmp(bn, sae->tmp->order) >= 0)
+		    crypto_bignum_cmp(bn, sae->tmp->order) >= 0) {
+			crypto_bignum_deinit(bn, 0);
 			continue;
+		}
 		break;
 	}