--- sbin/ipfw/ipfw2.c.orig	2017-04-10 20:47:20.140177000 +0700
+++ sbin/ipfw/ipfw2.c	2017-05-01 19:23:29.097139000 +0700
@@ -3176,7 +3176,6 @@ ipfw_delete(char *av[])
 
 	av++;
 	NEED1("missing rule specification");
-	memset(&rt, 0, sizeof(rt));
 	if ( *av && _substrcmp(*av, "set") == 0) {
 		/* Do not allow using the following syntax:
 		 *	ipfw set N delete set M
@@ -3189,6 +3188,7 @@ ipfw_delete(char *av[])
 
 	/* Rule number */
 	while (*av && isdigit(**av)) {
+		memset(&rt, 0, sizeof(rt));
 		i = strtol(*av, &sep, 10);
 		j = i;
 		if (*sep== '-')
@@ -5124,12 +5124,11 @@ ipfw_zero(int ac, char *av[], int optnam
 	char const *name = optname ? "RESETLOG" : "ZERO";
 
 	optname = optname ? IP_FW_XRESETLOG : IP_FW_XZERO;
-	memset(&rt, 0, sizeof(rt));
-
 	av++; ac--;
 
 	if (ac == 0) {
 		/* clear all entries */
+		memset(&rt, 0, sizeof(rt));
 		rt.flags = IPFW_RCFLAG_ALL;
 		if (do_range_cmd(optname, &rt) < 0)
 			err(EX_UNAVAILABLE, "setsockopt(IP_FW_X%s)", name);
@@ -5147,6 +5146,7 @@ ipfw_zero(int ac, char *av[], int optnam
 			if (errstr)
 				errx(EX_DATAERR,
 				    "invalid rule number %s\n", *av);
+			memset(&rt, 0, sizeof(rt));
 			rt.start_rule = arg;
 			rt.end_rule = arg;
 			rt.flags |= IPFW_RCFLAG_RANGE;