kdig: don't clear empty tsig_key (UBSAN)

diff --git a/src/libknot/tsig.c b/src/libknot/tsig.c
index 479004b9f65bfc3b7c42c45b340c5923a9589d31..35311a2997e9fdfba0dd37bbaf72aedc800a589d 100644 (file)
--- a/src/libknot/tsig.c
+++ b/src/libknot/tsig.c
@@ -1,4 +1,4 @@
-/*  Copyright (C) 2019 CZ.NIC, z.s.p.o. <knot-dns@labs.nic.cz>
+/*  Copyright (C) 2021 CZ.NIC, z.s.p.o. <knot-dns@labs.nic.cz>
 
     This program is free software: you can redistribute it and/or modify
     it under the terms of the GNU General Public License as published by
@@ -33,7 +33,9 @@ void knot_tsig_key_deinit(knot_tsig_key_t *key)
 
        knot_dname_free(key->name, NULL);
 
-       memzero(key->secret.data, key->secret.size);
+       if (key->secret.data) {
+               memzero(key->secret.data, key->secret.size);
+       }
        dnssec_binary_free(&key->secret);
 
        memzero(key, sizeof(*key));