ipvs: zero usvc and udest

Make sure that any otherwise uninitialised fields of usvc are zero.

This has been obvserved to cause a problem whereby the port of
fwmark services may end up as a non-zero value which causes
scheduling of a destination server to fail for persisitent services.

As observed by Deon van der Merwe <dvdm@truteq.co.za>.
This fix suggested by Julian Anastasov <ja@ssi.bg>.

For good measure also zero udest.

Cc: Deon van der Merwe <dvdm@truteq.co.za>
Acked-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Simon Horman <horms@verge.net.au>
Cc: stable@kernel.org
Signed-off-by: Patrick McHardy <kaber@trash.net>

net/netfilter/ipvs/ip_vs_ctl.c

@@ -2714,6 +2714,8 @@ static int ip_vs_genl_parse_service(struct ip_vs_service_user_kern *usvc,
 	if (!(nla_af && (nla_fwmark || (nla_port && nla_protocol && nla_addr))))
 		return -EINVAL;
 
+	memset(usvc, 0, sizeof(*usvc));
+
 	usvc->af = nla_get_u16(nla_af);
 #ifdef CONFIG_IP_VS_IPV6
 	if (usvc->af != AF_INET && usvc->af != AF_INET6)
@@ -2901,6 +2903,8 @@ static int ip_vs_genl_parse_dest(struct ip_vs_dest_user_kern *udest,
 	if (!(nla_addr && nla_port))
 		return -EINVAL;
 
+	memset(udest, 0, sizeof(*udest));
+
 	nla_memcpy(&udest->addr, nla_addr, sizeof(udest->addr));
 	udest->port = nla_get_u16(nla_port);