diff --git a/library/bignum.c b/library/bignum.c
index b221312..0cb9505 100644
--- a/library/bignum.c
+++ b/library/bignum.c
@@ -1813,7 +1813,7 @@
         /*
          * pick a random A, 1 < A < |X| - 1
          */
-        MPI_CHK( mpi_fill_random( &A, X->n, f_rng, p_rng ) );
+        MPI_CHK( mpi_fill_random( &A, X->n * ciL, f_rng, p_rng ) );
 
         if( mpi_cmp_mpi( &A, &W ) >= 0 )
         {
@@ -1885,7 +1885,7 @@
 
     n = BITS_TO_LIMBS( nbits );
 
-    MPI_CHK( mpi_fill_random( X, n, f_rng, p_rng ) );
+    MPI_CHK( mpi_fill_random( X, n * ciL, f_rng, p_rng ) );
 
     k = mpi_msb( X );
     if( k < nbits ) MPI_CHK( mpi_shift_l( X, nbits - k ) );
diff --git a/library/dhm.c b/library/dhm.c
index f9cef5e..dcbebc2 100644
--- a/library/dhm.c
+++ b/library/dhm.c
@@ -124,16 +124,14 @@
                      int (*f_rng)(void *, unsigned char *, size_t),
                      void *p_rng )
 {
-    int ret, n;
+    int ret;
     size_t n1, n2, n3;
     unsigned char *p;
 
     /*
      * Generate X as large as possible ( < P )
      */
-    n = x_size / sizeof( t_uint ) + 1;
-
-    mpi_fill_random( &ctx->X, n, f_rng, p_rng );
+    mpi_fill_random( &ctx->X, x_size, f_rng, p_rng );
 
     while( mpi_cmp_mpi( &ctx->X, &ctx->P ) >= 0 )
            mpi_shift_r( &ctx->X, 1 );
@@ -201,7 +199,7 @@
                      int (*f_rng)(void *, unsigned char *, size_t),
                      void *p_rng )
 {
-    int ret, n;
+    int ret;
 
     if( ctx == NULL || olen < 1 || olen > ctx->len )
         return( POLARSSL_ERR_DHM_BAD_INPUT_DATA );
@@ -209,9 +207,7 @@
     /*
      * generate X and calculate GX = G^X mod P
      */
-    n = x_size / sizeof( t_uint ) + 1;
-
-    mpi_fill_random( &ctx->X, n, f_rng, p_rng );
+    mpi_fill_random( &ctx->X, x_size, f_rng, p_rng );
 
     while( mpi_cmp_mpi( &ctx->X, &ctx->P ) >= 0 )
            mpi_shift_r( &ctx->X, 1 );