Move the getifaddrs() call below the interface checks that can cause

update_iface() to return early to avoid leaking the allocated memory if
any of the checks fail.

ok florian@ bluhm@ dlg@

Author: jmatthew

sbin/dhcp6leased/frontend.c

@@ -1,4 +1,4 @@
-/*	$OpenBSD: frontend.c,v 1.21 2025/04/27 16:22:33 florian Exp $	*/
+/*	$OpenBSD: frontend.c,v 1.22 2025/06/19 10:28:41 jmatthew Exp $	*/
 
 /*
  * Copyright (c) 2017, 2021, 2024 Florian Obser <[email protected]>
@@ -559,9 +559,6 @@ update_iface(uint32_t if_index)
 	int			 flags;
 	char			 ifnamebuf[IF_NAMESIZE], *if_name;
 
-	if (getifaddrs(&ifap) != 0)
-		fatal("getifaddrs");
-
 	if ((if_name = if_indextoname(if_index, ifnamebuf)) == NULL)
 		return;
 
@@ -571,6 +568,9 @@ update_iface(uint32_t if_index)
 	if (find_iface_conf(&frontend_conf->iface_list, if_name) == NULL)
 		return;
 
+	if (getifaddrs(&ifap) != 0)
+		fatal("getifaddrs");
+
 	memset(&ifinfo, 0, sizeof(ifinfo));
 	ifinfo.if_index = if_index;
 	ifinfo.link_state = -1;