SIOCGIFNETMASK_IN6 failing just means that someone delete the address

we are currently looking at. No need to fatal.
Found the hard way by naddy

diff --git a/usr.sbin/rad/frontend.c b/usr.sbin/rad/frontend.c
index 0a5a982..c452a84 100644 (file)
--- a/usr.sbin/rad/frontend.c
+++ b/usr.sbin/rad/frontend.c
@@ -1,4 +1,4 @@
-/*     $OpenBSD: frontend.c,v 1.15 2018/08/03 13:14:46 florian Exp $   */
+/*     $OpenBSD: frontend.c,v 1.16 2018/08/15 16:48:20 florian Exp $   */
 
 /*
  * Copyright (c) 2018 Florian Obser <florian@openbsd.org>
@@ -828,7 +828,7 @@ get_interface_prefixes(struct ra_iface *ra_iface, struct ra_prefix_conf
                memcpy(&ifr6.ifr_addr, sin6, sizeof(ifr6.ifr_addr));
                
                if (ioctl(ioctlsock, SIOCGIFNETMASK_IN6, (caddr_t)&ifr6) < 0)
-                       fatal("SIOCGIFNETMASK_IN6");
+                       continue; /* addr got deleted while we were looking */
 
                prefixlen = in6_mask2prefixlen(&((struct sockaddr_in6 *)
                    &ifr6.ifr_addr)->sin6_addr);