krb5 commit: Zap data when freeing krb5_spake_factor

https://github.com/krb5/krb5/commit/9cc94a3f1ce06a4430f684300a747ec079102403
commit 9cc94a3f1ce06a4430f684300a747ec079102403
Author: Greg Hudson <[email protected]>
Date:   Tue Mar 27 15:42:28 2018 -0400

    Zap data when freeing krb5_spake_factor
    
    krb5_spake_factor structures will sometimes hold sensitive data when
    second-factor SPAKE is implemented, so should be zapped when freed.
    
    ticket: 8647

 src/lib/krb5/krb/kfree.c |    4 +++-
 1 files changed, 3 insertions(+), 1 deletions(-)

diff --git a/src/lib/krb5/krb/kfree.c b/src/lib/krb5/krb/kfree.c
index e1ea149..71e7fca 100644
--- a/src/lib/krb5/krb/kfree.c
+++ b/src/lib/krb5/krb/kfree.c
@@ -897,7 +897,9 @@ k5_free_spake_factor(krb5_context context, krb5_spake_factor *val)
 {
     if (val == NULL)
         return;
-    krb5_free_data(context, val->data);
+    if (val->data != NULL)
+        zapfree(val->data->data, val->data->length);
+    free(val->data);
     free(val);
 }