On 12/14/18 9:14 PM, Roopa Prabhu wrote:
> @@ -4021,6 +4033,171 @@ static int rtnl_fdb_dump(struct sk_buff *skb, struct
> netlink_callback *cb)
> return skb->len;
> }
>
> +static int valid_fdb_get_strict(const struct nlmsghdr *nlh,
> + struct nlattr **tb, u8 *ndm_flags,
> + int *br_idx, int *brport_idx, u8 **addr,
> + u16 *vid, struct netlink_ext_ack *extack)
> +{
> + struct ndmsg *ndm;
> + int err, i;
> +
> + if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ndm))) {
> + NL_SET_ERR_MSG(extack, "Invalid header for fdb get request");
> + return -EINVAL;
> + }
> +
> + ndm = nlmsg_data(nlh);
> + if (ndm->ndm_pad1 || ndm->ndm_pad2 || ndm->ndm_state ||
> + ndm->ndm_type) {
> + NL_SET_ERR_MSG(extack, "Invalid values in header for fdb get
> request");
> + return -EINVAL;
> + }
> +
> + if (ndm->ndm_flags & ~(NTF_MASTER | NTF_SELF)) {
> + NL_SET_ERR_MSG(extack, "Invalid flags in header for fdb get
> request");
> + return -EINVAL;
> + }
> +
> + err = nlmsg_parse_strict(nlh, sizeof(struct ndmsg), tb, NDA_MAX,
> + nda_policy, extack);
> + if (err < 0)
> + return err;
> +
> + *ndm_flags = ndm->ndm_flags;
> + *brport_idx = ndm->ndm_ifindex;
> + for (i = 0; i <= NDA_MAX; ++i) {
> + if (!tb[i])
> + continue;
> +
> + switch (i) {
> + case NDA_MASTER:
> + if (nla_len(tb[i]) != sizeof(u32)) {
This is checked by the policy during the nlsmsg_parse.
> + NL_SET_ERR_MSG(extack, "Invalid MASTER
> attribute in fdb get request");
> + return -EINVAL;
> + }
> + *br_idx = nla_get_u32(tb[i]);
> + break;
> + case NDA_LLADDR:
> + if (!tb[i] || nla_len(tb[i]) != ETH_ALEN) {
The nla_len check is needed here, but '!tb[i]' is redundant with the
check after the for statement.
> + NL_SET_ERR_MSG(extack, "Invalid address in fdb
> get request");
> + return -EINVAL;
> + }
> + *addr = nla_data(tb[i]);
> + break;
> + case NDA_VLAN:
> + err = fdb_vid_parse(tb[i], vid, extack);
> + if (err)
> + return err;
> + break;
> + case NDA_VNI:
> + if (nla_len(tb[i]) != sizeof(u32)) {
And here the len is already checked by the policy.
> + NL_SET_ERR_MSG(extack, "Invalid VNI in fdb get
> request");
> + return err;
> + }
> + break;
> + default:
> + NL_SET_ERR_MSG(extack, "Unsupported attribute in fdb
> get request");
> + return -EINVAL;
> + }
> + }
> +
> + return 0;
> +}
> +
> +static int rtnl_fdb_get(struct sk_buff *in_skb, struct nlmsghdr *nlh,
> + struct netlink_ext_ack *extack)
> +{
> + struct net_device *dev = NULL, *br_dev = NULL;
> + const struct net_device_ops *ops = NULL;
> + struct net *net = sock_net(in_skb->sk);
> + struct nlattr *tb[NDA_MAX + 1];
> + struct sk_buff *skb;
> + int brport_idx = 0;
> + u8 ndm_flags = 0;
> + int br_idx = 0;
> + u8 *addr = NULL;
> + u16 vid = 0;
> + int err;
> +
> + err = valid_fdb_get_strict(nlh, tb, &ndm_flags, &br_idx,
> + &brport_idx, &addr, &vid, extack);
> + if (err < 0)
> + return err;
> +
> + if (brport_idx) {
> + dev = __dev_get_by_index(net, brport_idx);
> + if (!dev) {
> + NL_SET_ERR_MSG(extack, "Unknown device ifindex");
> + return -ENODEV;
> + }
> + }
> +
> + if (br_idx) {
> + if (dev) {
> + NL_SET_ERR_MSG(extack, "Master and device are mutually
> exclusive");
> + return -EINVAL;
> + }
> +
> + br_dev = __dev_get_by_index(net, br_idx);
> + if (!br_dev) {
> + NL_SET_ERR_MSG(extack, "Invalid master ifindex");
> + return -EINVAL;
> + }
> + ops = br_dev->netdev_ops;
> + }
> +
> + if (dev) {
> + if (!ndm_flags || (ndm_flags & NTF_MASTER)) {
> + if (!(dev->priv_flags & IFF_BRIDGE_PORT)) {
> + NL_SET_ERR_MSG(extack, "Device is not a bridge
> port");
> + return -EINVAL;
> + }
> + br_dev = netdev_master_upper_dev_get(dev);
> + if (!br_dev) {
> + NL_SET_ERR_MSG(extack, "Master of device not
> found");
> + return -EINVAL;
> + }
> + ops = br_dev->netdev_ops;
> + } else {
> + if (!(ndm_flags & NTF_SELF)) {
> + NL_SET_ERR_MSG(extack, "Missing NTF_SELF");
> + return -EINVAL;
> + }
> + ops = dev->netdev_ops;
> + }
> + }
> +
> + if (!br_dev && !dev) {
> + NL_SET_ERR_MSG(extack, "No device specified");
> + return -ENODEV;
> + }
> +
> + if (!ops || !ops->ndo_fdb_get) {
> + NL_SET_ERR_MSG(extack, "Fdb get operation not supported by
> device");
> + return -EOPNOTSUPP;
> + }
> +
> + skb = nlmsg_new(NLMSG_GOODSIZE, GFP_KERNEL);
> + if (!skb)
> + return -ENOBUFS;
> +
> + if (br_dev)
> + err = ops->ndo_fdb_get(skb, tb, br_dev, addr, vid,
> + NETLINK_CB(in_skb).portid,
> + nlh->nlmsg_seq, extack);
> + else
> + err = ops->ndo_fdb_get(skb, tb, dev, addr, vid,
> + NETLINK_CB(in_skb).portid,
> + nlh->nlmsg_seq, extack);
The above can be simplified to one ndo_fdb_get call.
if (br_dev)
dev = br_dev;
err = ops->ndo_fdb_get(skb, tb, dev, addr, vid,
NETLINK_CB(in_skb).portid,
nlh->nlmsg_seq, extack);
Or unless I am missing something, br_dev as a separate variable is not
really needed and it would simplify things just a bit.
> + if (err)
> + goto out;
> +
> + return rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid);
> +out:
> + kfree_skb(skb);
> + return err;
> +}
> +
> static int brport_nla_put_flag(struct sk_buff *skb, u32 flags, u32 mask,
> unsigned int attrnum, unsigned int flag)
> {
> @@ -5081,7 +5258,7 @@ void __init rtnetlink_init(void)
>
> rtnl_register(PF_BRIDGE, RTM_NEWNEIGH, rtnl_fdb_add, NULL, 0);
> rtnl_register(PF_BRIDGE, RTM_DELNEIGH, rtnl_fdb_del, NULL, 0);
> - rtnl_register(PF_BRIDGE, RTM_GETNEIGH, NULL, rtnl_fdb_dump, 0);
> + rtnl_register(PF_BRIDGE, RTM_GETNEIGH, rtnl_fdb_get, rtnl_fdb_dump, 0);
>
> rtnl_register(PF_BRIDGE, RTM_GETLINK, NULL, rtnl_bridge_getlink, 0);
> rtnl_register(PF_BRIDGE, RTM_DELLINK, rtnl_bridge_dellink, NULL, 0);
>
