1 files changed, 4 insertions, 1 deletions
diff --git a/extmod/modurandom.c b/extmod/modurandom.c
index f44510be9b..21fbac6942 100644
--- a/extmod/modurandom.c
+++ b/extmod/modurandom.c
@@ -87,9 +87,12 @@ STATIC uint32_t yasmarang_randbelow(uint32_t n) {
 
 STATIC mp_obj_t mod_urandom_getrandbits(mp_obj_t num_in) {
     int n = mp_obj_get_int(num_in);
-    if (n > 32 || n == 0) {
+    if (n > 32 || n < 0) {
         mp_raise_ValueError(MP_ERROR_TEXT("bits must be 32 or less"));
     }
+    if (n == 0) {
+        return MP_OBJ_NEW_SMALL_INT(0);
+    }
     uint32_t mask = ~0;
     // Beware of C undefined behavior when shifting by >= than bit size
     mask >>= (32 - n);