From: Stephen Hemminger <sthemmin@microsoft.com>
Date: Fri, 9 Mar 2018 02:02:19 +0000 (-0800)
Subject: ipmroute: better error message if no kernel mroute
X-Git-Tag: v4.17.0~60^2
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=e06e9a6bac6a8e16ee6580635f891bd2dfd1a1b6;p=thirdparty%2Fiproute2.git

ipmroute: better error message if no kernel mroute

If kernel does not support the IP multicast address family,
then it will report all routes (PF_UNSPEC).
Give the user a better error message and abort the command.

Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: David Ahern <dsahern@gmail.com>
---

diff --git a/ip/ipmroute.c b/ip/ipmroute.c
index 03087b6c4..59c5b7718 100644
--- a/ip/ipmroute.c
+++ b/ip/ipmroute.c
@@ -75,10 +75,11 @@ int print_mroute(const struct sockaddr_nl *who, struct nlmsghdr *n, void *arg)
 		fprintf(stderr, "BUG: wrong nlmsg len %d\n", len);
 		return -1;
 	}
+
 	if (r->rtm_type != RTN_MULTICAST) {
-		fprintf(stderr, "Not a multicast route (type: %s)\n",
-			rtnl_rtntype_n2a(r->rtm_type, b1, sizeof(b1)));
-		return 0;
+		fprintf(stderr,
+			"Non multicast route received, kernel does support IP multicast?\n");
+		return -1;
 	}
 
 	parse_rtattr(tb, RTA_MAX, RTM_RTA(r), len);