diff --git a/usr.sbin/faithd/faithd.c b/usr.sbin/faithd/faithd.c
index 4d4f19ec1ebd..c314b74bea49 100644
--- a/usr.sbin/faithd/faithd.c
+++ b/usr.sbin/faithd/faithd.c
@@ -381,7 +381,7 @@ play_service(int s_wld)
 	 * Wait, accept, fork, faith....
 	 */
 again:
-	setproctitle(procname);
+	setproctitle("%s", procname);
 
 	FD_ZERO(&rfds);
 	FD_SET(s_wld, &rfds);