From: Stephen Worley <sworley@cumulusnetworks.com>
Date: Mon, 23 Jul 2018 22:33:53 +0000 (-0400)
Subject: zebra: Add check for nexthop loop to prevent hanging
X-Git-Tag: frr-6.1-dev~140^2
X-Git-Url: https://git.puffer.fish/?a=commitdiff_plain;h=3c04071d996f84f265776f068ff21dc48d895139;p=matthieu%2Ffrr.git

zebra: Add check for nexthop loop to prevent hanging

Bad nexthop messages from netlink were causing zebra
to hang here. Added a check to verify the length
of the nexthop so it doesn't keep trying to read.

Signed-off-by: Stephen Worley <sworley@cumulusnetworks.com>
---

diff --git a/zebra/rt_netlink.c b/zebra/rt_netlink.c
index b346247d4b..ec84c4c622 100644
--- a/zebra/rt_netlink.c
+++ b/zebra/rt_netlink.c
@@ -581,6 +581,9 @@ static int netlink_route_change_read_unicast(struct nlmsghdr *h, ns_id_t ns_id,
 					route_entry_nexthop_ifindex_add(
 						re, index, nh_vrf_id);
 
+				if (rtnh->rtnh_len == 0)
+					break;
+
 				len -= NLMSG_ALIGN(rtnh->rtnh_len);
 				rtnh = RTNH_NEXT(rtnh);
 			}
@@ -701,6 +704,9 @@ static int netlink_route_change_read_multicast(struct nlmsghdr *h,
 			oif[oif_count] = rtnh->rtnh_ifindex;
 			oif_count++;
 
+			if (rtnh->rtnh_len == 0)
+				break;
+
 			len -= NLMSG_ALIGN(rtnh->rtnh_len);
 			rtnh = RTNH_NEXT(rtnh);
 		}