diff --git a/library/bignum.c b/library/bignum.c
index d3d02b1a03..606bca456b 100644
--- a/library/bignum.c
+++ b/library/bignum.c
@@ -2329,7 +2329,8 @@ static int mpi_miller_rabin( const mbedtls_mpi *X, size_t rounds,
             }
 
             if (count++ > 30) {
-                return MBEDTLS_ERR_MPI_NOT_ACCEPTABLE;
+                ret = MBEDTLS_ERR_MPI_NOT_ACCEPTABLE;
+                goto cleanup;
             }
 
         } while ( mbedtls_mpi_cmp_mpi( &A, &W ) >= 0 ||