On 19/10/15 02:20, Roopa Prabhu wrote:
@@ -159,6 +137,7 @@ static int mpls_forward(struct sk_buff *skb, struct net_device *dev, struct net *net = dev_net(dev); struct mpls_shim_hdr *hdr; struct mpls_route *rt; + struct mpls_nh *nh; struct mpls_entry_decoded dec; struct net_device *out_dev; struct mpls_dev *mdev; @@ -166,6 +145,7 @@ static int mpls_forward(struct sk_buff *skb, struct net_device *dev, unsigned int new_header_size; unsigned int mtu; int err; + int nhidx;
nhidx looks to be unused. Remove?
/* Careful this entire function runs inside of an rcu critical section */ @@ -196,8 +176,12 @@ static int mpls_forward(struct sk_buff *skb, struct net_device *dev, if (!rt) goto drop; + nh = mpls_select_multipath(rt); + if (!nh) + goto drop; + /* Find the output device */ - out_dev = rcu_dereference(rt->rt_dev); + out_dev = rcu_dereference(nh->nh_dev); if (!mpls_output_possible(out_dev)) goto drop; @@ -212,7 +196,7 @@ static int mpls_forward(struct sk_buff *skb, struct net_device *dev, dec.ttl -= 1; /* Verify the destination can hold the packet */ - new_header_size = mpls_rt_header_size(rt); + new_header_size = mpls_nh_header_size(nh); mtu = mpls_dev_mtu(out_dev); if (mpls_pkt_too_big(skb, mtu - new_header_size)) goto drop; @@ -240,13 +224,14 @@ static int mpls_forward(struct sk_buff *skb, struct net_device *dev, /* Push the new labels */ hdr = mpls_hdr(skb); bos = dec.bos; - for (i = rt->rt_labels - 1; i >= 0; i--) { - hdr[i] = mpls_entry_encode(rt->rt_label[i], dec.ttl, 0, bos); + for (i = nh->nh_labels - 1; i >= 0; i--) { + hdr[i] = mpls_entry_encode(nh->nh_label[i], + dec.ttl, 0, bos); bos = false; } } - err = neigh_xmit(rt->rt_via_table, out_dev, rt->rt_via, skb); + err = neigh_xmit(nh->nh_via_table, out_dev, nh->nh_via, skb); if (err) net_dbg_ratelimited("%s: packet transmission failed: %d\n", __func__, err);
return dev; } +static int mpls_nh_assign_dev(struct net *net, struct mpls_nh *nh, int oif) +{ + struct net_device *dev = NULL; + int err = -ENODEV; + + dev = find_outdev(net, nh, oif); + if (IS_ERR(dev)) { + err = PTR_ERR(dev); + dev = NULL; + goto errout; + } + + /* Ensure this is a supported device */ + err = -EINVAL; + if (!mpls_dev_get(dev)) + goto errout; + + /* For now just support ethernet devices */ + if ((dev->type != ARPHRD_ETHER) && (dev->type != ARPHRD_LOOPBACK)) + goto errout; + + RCU_INIT_POINTER(nh->nh_dev, dev); + dev_put(dev);
If it's safe to not keep a reference to dev (i.e. because the device cannot go away while a netlink message is being processed), then why not just change find_outdev to use __dev_get_by_index? If the dev can go away during this, then we could end up adding an mpls route that points to a freed interface, because until we've added the route to the label table mpls_ifdown won't find it.
+ + return 0; + +errout: + if (dev) + dev_put(dev); + return err; +} +
} EXPORT_SYMBOL_GPL(nla_get_labels); +int nla_get_via(const struct nlattr *nla, u8 *via_alen, + u8 *via_table, u8 via_addr[]) +{ + struct rtvia *via = nla_data(nla); + int err = -EINVAL; + u8 alen;
This should be an int to avoid nexthop address lengths > 255 wrapping and possibly accepted instead of rejected.
+ + if (nla_len(nla) < offsetof(struct rtvia, rtvia_addr)) + goto errout; + alen = nla_len(nla) - + offsetof(struct rtvia, rtvia_addr); + if (alen > MAX_VIA_ALEN) + goto errout; + + /* Validate the address family */ + switch(via->rtvia_family) { + case AF_PACKET: + *via_table = NEIGH_LINK_TABLE; + break; + case AF_INET: + *via_table = NEIGH_ARP_TABLE; + if (alen != 4) + goto errout; + break; + case AF_INET6: + *via_table = NEIGH_ND_TABLE; + if (alen != 16) + goto errout; + break; + default: + /* Unsupported address family */ + goto errout; + } + + memcpy(via_addr, via->rtvia_addr, alen); + *via_alen = alen; + err = 0; + +errout: + return err; +} + static int rtm_to_route_config(struct sk_buff *skb, struct nlmsghdr *nlh, struct mpls_route_config *cfg) {
Otherwise, looks good. Thanks, Rob -- 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