ip -6 addr add dead::1/128 dev eth0 sleep 5 ip -6 route add default via dead::1/128 -> fails ip -6 addr add dead::1/128 dev eth0 ip -6 route add default via dead::1/128 -> succeeds
reason is that if (nonsensensical) route above is added, dead::1 is still subject to DAD, so the route lookup will pick eth0 as outdev due to the prefix route that is added before DAD work is started. Add explicit test that checks if nexthop gateway is a local address. Link: https://bugzilla.redhat.com/show_bug.cgi?id=1167969 Signed-off-by: Florian Westphal <f...@strlen.de> --- diff --git a/net/ipv6/route.c b/net/ipv6/route.c index 6f4a350..98fce6f 100644 --- a/net/ipv6/route.c +++ b/net/ipv6/route.c @@ -1624,6 +1624,16 @@ int ip6_route_add(struct fib6_config *cfg) int gwa_type; gw_addr = &cfg->fc_gateway; + + /* if gw_addr is local we will fail to detect this in case + * address is still TENTATIVE (DAD in progress). rt6_lookup() + * will return already-added prefix route via interface that + * prefix route was assigned to, which might be non-loopback. + */ + err = -EINVAL; + if (ipv6_chk_addr_and_flags(net, gw_addr, NULL, 0, 0)) + goto out; + rt->rt6i_gateway = *gw_addr; gwa_type = ipv6_addr_type(gw_addr); @@ -1637,7 +1647,6 @@ int ip6_route_add(struct fib6_config *cfg) (SIT, PtP, NBMA NOARP links) it is handy to allow some exceptions. --ANK */ - err = -EINVAL; if (!(gwa_type & IPV6_ADDR_UNICAST)) goto out; -- 2.0.5 -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
