bpf: Handle ipv6 gateway in bpf_ipv4_fib_lookup

Update bpf_ipv4_fib_lookup to handle an ipv6 gateway.

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

diff --git a/net/core/filter.c b/net/core/filter.c
index abd5b6ce031aeac083e2fc4dc65b86a9e4733027..41f633cf4fc17c48f20f379c7da93ee3580e2777 100644 (file)
--- a/net/core/filter.c
+++ b/net/core/filter.c
@@ -4639,15 +4639,26 @@ static int bpf_ipv4_fib_lookup(struct net *net, struct bpf_fib_lookup *params,
                return BPF_FIB_LKUP_RET_UNSUPP_LWT;
 
        dev = nhc->nhc_dev;
-       if (nhc->nhc_gw_family)
-               params->ipv4_dst = nhc->nhc_gw.ipv4;
 
        params->rt_metric = res.fi->fib_priority;
 
        /* xdp and cls_bpf programs are run in RCU-bh so
         * rcu_read_lock_bh is not needed here
         */
-       neigh = __ipv4_neigh_lookup_noref(dev, (__force u32)params->ipv4_dst);
+       if (likely(nhc->nhc_gw_family != AF_INET6)) {
+               if (nhc->nhc_gw_family)
+                       params->ipv4_dst = nhc->nhc_gw.ipv4;
+
+               neigh = __ipv4_neigh_lookup_noref(dev,
+                                                (__force u32)params->ipv4_dst);
+       } else {
+               struct in6_addr *dst = (struct in6_addr *)params->ipv6_dst;
+
+               params->family = AF_INET6;
+               *dst = nhc->nhc_gw.ipv6;
+               neigh = __ipv6_neigh_lookup_noref_stub(dev, dst);
+       }
+
        if (!neigh)
                return BPF_FIB_LKUP_RET_NO_NEIGH;