rtnetlink: Update rtnl_stats_dump for strict data checking

Update rtnl_stats_dump for strict data checking. If the flag is set,
the dump request is expected to have an if_stats_msg struct as the header.
All elements of the struct are expected to be 0 except filter_mask which
must be non-0 (legacy behavior). No attributes are supported.

Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
David Ahern 2018-10-07 20:16:32 -07:00 committed by David S. Miller
parent 2d011be8c0
commit 841891ec0c

View file

@ -4680,6 +4680,7 @@ static int rtnl_stats_get(struct sk_buff *skb, struct nlmsghdr *nlh,
static int rtnl_stats_dump(struct sk_buff *skb, struct netlink_callback *cb)
{
struct netlink_ext_ack *extack = cb->extack;
int h, s_h, err, s_idx, s_idxattr, s_prividx;
struct net *net = sock_net(skb->sk);
unsigned int flags = NLM_F_MULTI;
@ -4696,13 +4697,32 @@ static int rtnl_stats_dump(struct sk_buff *skb, struct netlink_callback *cb)
cb->seq = net->dev_base_seq;
if (nlmsg_len(cb->nlh) < sizeof(*ifsm))
if (nlmsg_len(cb->nlh) < sizeof(*ifsm)) {
NL_SET_ERR_MSG(extack, "Invalid header for stats dump");
return -EINVAL;
}
ifsm = nlmsg_data(cb->nlh);
/* only requests using NLM_F_DUMP_PROPER_HDR can pass data to
* influence the dump. The legacy exception is filter_mask.
*/
if (cb->strict_check) {
if (ifsm->pad1 || ifsm->pad2 || ifsm->ifindex) {
NL_SET_ERR_MSG(extack, "Invalid values in header for stats dump request");
return -EINVAL;
}
if (nlmsg_attrlen(cb->nlh, sizeof(*ifsm))) {
NL_SET_ERR_MSG(extack, "Invalid attributes after stats header");
return -EINVAL;
}
}
filter_mask = ifsm->filter_mask;
if (!filter_mask)
if (!filter_mask) {
NL_SET_ERR_MSG(extack, "Filter mask must be set for stats dump");
return -EINVAL;
}
for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
idx = 0;