On Fri, Dec 14, 2018 at 9:55 AM David Ahern <d...@cumulusnetworks.com> wrote:
>
> On 12/14/18 10:43 AM, Roopa Prabhu wrote:
> > diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c
> > index f8bdb8ad..fcea76b 100644
> > --- a/net/core/rtnetlink.c
> > +++ b/net/core/rtnetlink.c
> > @@ -4021,6 +4021,111 @@ static int rtnl_fdb_dump(struct sk_buff *skb,
> > struct netlink_callback *cb)
> > return skb->len;
> > }
> >
> > +static int rtnl_fdb_get(struct sk_buff *in_skb, struct nlmsghdr *nlh,
> > + struct netlink_ext_ack *extack)
> > +{
> > + const struct net_device_ops *ops = NULL;
> > + struct net *net = sock_net(in_skb->sk);
> > + struct net_device *dev = NULL, *br_dev = NULL;
> > + struct nlattr *tb[NDA_MAX + 1];
> > + struct sk_buff *skb;
> > + struct ndmsg *ndm;
> > + int br_idx = 0;
> > + u8 *addr;
> > + u16 vid;
> > + int err;
> > +
> > + err = nlmsg_parse(nlh, sizeof(*ndm), tb, NDA_MAX, NULL, extack);
>
> New stuff should go in with strict checking, so nlmsg_parse_strict and a
> check for any unsupported attributes (NDA) or ndm entries in the request.
makes sense.
>
> Also, please add an nla_policy for easier NDA attributes ...
yes agreed. NDA attrs have not had a policy.
maybe an incremental patch ?, NDA_* attributes are used in bridge
vxlan and neighbour code, need a common place to put the policy.
(suggestions ?)
>
> > + if (err < 0)
> > + return err;
> > +
> > + ndm = nlmsg_data(nlh);
> > + if (ndm->ndm_ifindex) {
> > + dev = __dev_get_by_index(net, ndm->ndm_ifindex);
> > + if (!dev) {
> > + NL_SET_ERR_MSG(extack, "unknown dev ifindex");
>
> General comment on all of the extack messages: No abbreviations in the
> message, and it is nice to always start with a capital letter. "Unknown
> device index"
ack,
will send a v2
>
> > + return -ENODEV;
> > + }
> > + }
> > +
> > + if (!tb[NDA_LLADDR] || nla_len(tb[NDA_LLADDR]) != ETH_ALEN) {
> > + NL_SET_ERR_MSG(extack, "invalid address");
> > + return -EINVAL;
> > + }
> > +
> > + addr = nla_data(tb[NDA_LLADDR]);
> > +
> > + err = fdb_vid_parse(tb[NDA_VLAN], &vid, extack);
> > + if (err)
> > + return err;
> > +
> > + if (tb[NDA_MASTER]) {
> > + if (dev) {
> > + NL_SET_ERR_MSG(extack, "master and dev are mutually
> > exclusive");
> > + return -EINVAL;
> > + }
> > +
> > + br_idx = nla_get_u32(tb[NDA_MASTER]);
>
> ... so you know that NDA_MASTER is a u32.
>
> > + 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;
> > + }
> > +
>
