On Tue, Mar 26, 2019 at 08:29:34PM -0700, David Ahern wrote:
> +int fib6_nh_init(struct net *net, struct fib6_nh *fib6_nh,
> + struct fib6_config *cfg, gfp_t gfp_flags,
> + struct netlink_ext_ack *extack)
> +{
> + struct net_device *dev = NULL;
> + struct inet6_dev *idev = NULL;
> + int addr_type;
> + int err;
> +
> + err = -ENODEV;
> + if (cfg->fc_ifindex) {
> + dev = dev_get_by_index(net, cfg->fc_ifindex);
> + if (!dev)
> + goto out;
> + idev = in6_dev_get(dev);
> + if (!idev)
> + goto out;
> + }
> +
> + if (cfg->fc_flags & RTNH_F_ONLINK) {
> + if (!dev) {
> + NL_SET_ERR_MSG(extack,
> + "Nexthop device required for onlink");
> + goto out;
> + }
> +
> + if (!(dev->flags & IFF_UP)) {
> + NL_SET_ERR_MSG(extack, "Nexthop device is not up");
> + err = -ENETDOWN;
> + goto out;
> + }
> +
> + fib6_nh->nh_flags |= RTNH_F_ONLINK;
> + }
> +
> + if (cfg->fc_encap) {
> + struct lwtunnel_state *lwtstate;
> +
> + err = lwtunnel_build_state(cfg->fc_encap_type,
> + cfg->fc_encap, AF_INET6, cfg,
> + &lwtstate, extack);
> + if (err)
> + goto out;
> +
> + fib6_nh->nh_lwtstate = lwtstate_get(lwtstate);
> + }
> +
> + fib6_nh->nh_weight = 1;
> +
> + /* We cannot add true routes via loopback here,
> + * they would result in kernel looping; promote them to reject routes
> + */
> + addr_type = ipv6_addr_type(&cfg->fc_dst);
> + if ((cfg->fc_flags & RTF_REJECT) ||
> + (dev && (dev->flags & IFF_LOOPBACK) &&
> + !(addr_type & IPV6_ADDR_LOOPBACK) &&
> + !(cfg->fc_flags & RTF_LOCAL))) {
> + /* hold loopback dev/idev if we haven't done so. */
> + if (dev != net->loopback_dev) {
> + if (dev) {
> + dev_put(dev);
> + in6_dev_put(idev);
> + }
> + dev = net->loopback_dev;
> + dev_hold(dev);
> + idev = in6_dev_get(dev);
> + if (!idev) {
> + err = -ENODEV;
> + goto out;
Same comment as previous patch. Earlier in the function you take a
reference on the LWT object, but don't drop it in error path and instead
rely on the error path of ip6_route_info_create() to take care of that.
> + }
> + }
> + cfg->fc_flags = RTF_REJECT | RTF_NONEXTHOP;
> + goto set_dev;
> + }
> +
> + if (cfg->fc_flags & RTF_GATEWAY) {
> + err = ip6_validate_gw(net, cfg, &dev, &idev, extack);
> + if (err)
> + goto out;
> +
> + fib6_nh->nh_gw = cfg->fc_gateway;
> + }
> +
> + err = -ENODEV;
> + if (!dev)
> + goto out;
> +
> + if (idev->cnf.disable_ipv6) {
> + NL_SET_ERR_MSG(extack, "IPv6 is disabled on nexthop device");
> + err = -EACCES;
> + goto out;
> + }
> +
> + if (!(dev->flags & IFF_UP) && !cfg->fc_ignore_dev_down) {
> + NL_SET_ERR_MSG(extack, "Nexthop device is not up");
> + err = -ENETDOWN;
> + goto out;
> + }
> +
> + if (!(cfg->fc_flags & (RTF_LOCAL | RTF_ANYCAST)) &&
> + !netif_carrier_ok(dev))
> + fib6_nh->nh_flags |= RTNH_F_LINKDOWN;
> +
> +set_dev:
> + fib6_nh->nh_dev = dev;
> + err = 0;
> +out:
> + if (idev)
> + in6_dev_put(idev);
> +
> + if (err && dev)
> + dev_put(dev);
> +
> + return err;
> +}
