ipv6: Handle all fib6_nh in a nexthop in rt6_nlmsg_size

Add a hook in rt6_nlmsg_size to handle nexthop struct in a fib6_info.
rt6_nh_nlmsg_size is used to sum the space needed for all nexthops in
the fib entry.

Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/net/ipv6/route.c b/net/ipv6/route.c
index 740df72..d1139ef 100644 (file)
--- a/net/ipv6/route.c
+++ b/net/ipv6/route.c
@@ -100,7 +100,7 @@ static void         rt6_do_redirect(struct dst_entry *dst, struct sock *sk,
                                        struct sk_buff *skb);
 static int rt6_score_route(const struct fib6_nh *nh, u32 fib6_flags, int oif,
                           int strict);
-static size_t rt6_nlmsg_size(struct fib6_info *rt);
+static size_t rt6_nlmsg_size(struct fib6_info *f6i);
 static int rt6_fill_node(struct net *net, struct sk_buff *skb,
                         struct fib6_info *rt, struct dst_entry *dst,
                         struct in6_addr *dest, struct in6_addr *src,
@@ -4935,20 +4935,46 @@ static int inet6_rtm_newroute(struct sk_buff *skb, struct nlmsghdr *nlh,
                return ip6_route_add(&cfg, GFP_KERNEL, extack);
 }
 
-static size_t rt6_nlmsg_size(struct fib6_info *rt)
+/* add the overhead of this fib6_nh to nexthop_len */
+static int rt6_nh_nlmsg_size(struct fib6_nh *nh, void *arg)
 {
-       int nexthop_len = 0;
+       int *nexthop_len = arg;
 
-       if (rt->nh)
-               nexthop_len += nla_total_size(4); /* RTA_NH_ID */
+       *nexthop_len += nla_total_size(0)        /* RTA_MULTIPATH */
+                    + NLA_ALIGN(sizeof(struct rtnexthop))
+                    + nla_total_size(16); /* RTA_GATEWAY */
+
+       if (nh->fib_nh_lws) {
+               /* RTA_ENCAP_TYPE */
+               *nexthop_len += lwtunnel_get_encap_size(nh->fib_nh_lws);
+               /* RTA_ENCAP */
+               *nexthop_len += nla_total_size(2);
+       }
 
-       if (rt->fib6_nsiblings) {
-               nexthop_len = nla_total_size(0)  /* RTA_MULTIPATH */
-                           + NLA_ALIGN(sizeof(struct rtnexthop))
-                           + nla_total_size(16) /* RTA_GATEWAY */
-                           + lwtunnel_get_encap_size(rt->fib6_nh->fib_nh_lws);
+       return 0;
+}
 
-               nexthop_len *= rt->fib6_nsiblings;
+static size_t rt6_nlmsg_size(struct fib6_info *f6i)
+{
+       int nexthop_len;
+
+       if (f6i->nh) {
+               nexthop_len = nla_total_size(4); /* RTA_NH_ID */
+               nexthop_for_each_fib6_nh(f6i->nh, rt6_nh_nlmsg_size,
+                                        &nexthop_len);
+       } else {
+               struct fib6_nh *nh = f6i->fib6_nh;
+
+               nexthop_len = 0;
+               if (f6i->fib6_nsiblings) {
+                       nexthop_len = nla_total_size(0)  /* RTA_MULTIPATH */
+                                   + NLA_ALIGN(sizeof(struct rtnexthop))
+                                   + nla_total_size(16) /* RTA_GATEWAY */
+                                   + lwtunnel_get_encap_size(nh->fib_nh_lws);
+
+                       nexthop_len *= f6i->fib6_nsiblings;
+               }
+               nexthop_len += lwtunnel_get_encap_size(nh->fib_nh_lws);
        }
 
        return NLMSG_ALIGN(sizeof(struct rtmsg))
@@ -4964,7 +4990,6 @@ static size_t rt6_nlmsg_size(struct fib6_info *rt)
               + nla_total_size(sizeof(struct rta_cacheinfo))
               + nla_total_size(TCP_CA_NAME_MAX) /* RTAX_CC_ALGO */
               + nla_total_size(1) /* RTA_PREF */
-              + lwtunnel_get_encap_size(rt->fib6_nh->fib_nh_lws)
               + nexthop_len;
 }