Fix small UI issues

- in EVP_read_pw_string_min(), the return value from UI_add_* wasn't
  properly checked
- in UI_process(), |state| was never made NULL, which means an error
  when closing the session wouldn't be accurately reported.

Reviewed-by: Paul Dale <paul.dale@oracle.com>
(Merged from https://github.com/openssl/openssl/pull/3849)

1 files changed, 11 insertions, 9 deletions

diff --git a/crypto/evp/evp_key.c b/crypto/evp/evp_key.c
index 0d63e4f5bf..670276d1dc 100644
--- a/crypto/evp/evp_key.c
+++ b/crypto/evp/evp_key.c
@@ -48,7 +48,7 @@ int EVP_read_pw_string(char *buf, int len, const char *prompt, int verify)
 int EVP_read_pw_string_min(char *buf, int min, int len, const char *prompt,
                            int verify)
 {
-    int ret;
+    int ret = -1;
     char buff[BUFSIZ];
     UI *ui;
 
@@ -56,16 +56,18 @@ int EVP_read_pw_string_min(char *buf, int min, int len, const char *prompt,
         prompt = prompt_string;
     ui = UI_new();
     if (ui == NULL)
-        return -1;
-    UI_add_input_string(ui, prompt, 0, buf, min,
-                        (len >= BUFSIZ) ? BUFSIZ - 1 : len);
-    if (verify)
-        UI_add_verify_string(ui, prompt, 0,
-                             buff, min, (len >= BUFSIZ) ? BUFSIZ - 1 : len,
-                             buf);
+        return ret;
+    if (UI_add_input_string(ui, prompt, 0, buf, min,
+                            (len >= BUFSIZ) ? BUFSIZ - 1 : len) < 0
+        || (verify
+            && UI_add_verify_string(ui, prompt, 0, buff, min,
+                                    (len >= BUFSIZ) ? BUFSIZ - 1 : len,
+                                    buf) < 0))
+        goto end;
     ret = UI_process(ui);
-    UI_free(ui);
     OPENSSL_cleanse(buff, BUFSIZ);
+ end:
+    UI_free(ui);
     return ret;
 }