diff -up openssl-1.0.2i/engines/e_chil.c.chil openssl-1.0.2i/engines/e_chil.c
--- openssl-1.0.2i/engines/e_chil.c.chil 2016-09-22 12:23:06.000000000 +0200
+++ openssl-1.0.2i/engines/e_chil.c 2016-09-22 13:49:32.532017102 +0200
@@ -1274,6 +1274,11 @@ static int hwcrhk_insert_card(const char
UI *ui;
void *callback_data = NULL;
UI_METHOD *ui_method = NULL;
+ /* Despite what the documentation says prompt_info can be
+ * an empty string.
+ */
+ if (prompt_info && !*prompt_info)
+ prompt_info = NULL;
if (cactx) {
if (cactx->ui_method)