- Fix zonemd unsupported algo check to set reason to NULL before the

check routine, but after malformed checks, to get the correct NULL
  output when the digest matches.

doc/Changelog

@@ -8,6 +8,9 @@
 	  and check for success for debug printout.
 	- Fix zonemd unsupported algo check to print unsupported reason before
 	  zeroing it.
+	- Fix zonemd unsupported algo check to set reason to NULL before the
+	  check routine, but after malformed checks, to get the correct NULL
+	  output when the digest matches.
 
 25 March 2022: Wouter
 	- Fix spelling error in comment in sldns_str2wire_svcparam_key_lookup.

services/authzone.c

@@ -1932,6 +1932,7 @@ static int auth_zone_zonemd_check_hash(struct auth_zone* z,
 			only_unsupported = 0;
 			continue;
 		}
+		*reason = NULL;
 		if(auth_zone_generate_zonemd_check(z, scheme, hashalgo,
 			hash, hashlen, region, buf, reason)) {
 			/* success */