On Thu, Oct 04, 2018 at 02:33:47PM -0700, David Ahern wrote:
> From: David Ahern <dsah...@gmail.com>
>
> Update ipmr_rtm_dumplink for strict data checking. If the flag is set,
> the dump request is expected to have an ifinfomsg struct as the header.
> All elements of the struct are expected to be 0 and no attributes can
> be appended.
>
> Signed-off-by: David Ahern <dsah...@gmail.com>
Just one really tiny nit below. :)
Acked-by: Christian Brauner <christ...@brauner.io>
> ---
> net/ipv4/ipmr.c | 32 ++++++++++++++++++++++++++++++++
> 1 file changed, 32 insertions(+)
>
> diff --git a/net/ipv4/ipmr.c b/net/ipv4/ipmr.c
> index 5660adcf7a04..e6c48e08d53d 100644
> --- a/net/ipv4/ipmr.c
> +++ b/net/ipv4/ipmr.c
> @@ -2710,6 +2710,31 @@ static bool ipmr_fill_vif(struct mr_table *mrt, u32
> vifid, struct sk_buff *skb)
> return true;
> }
>
> +static int ipmr_valid_dumplink(const struct nlmsghdr *nlh,
> + struct netlink_ext_ack *extack)
> +{
> + struct ifinfomsg *ifm;
> +
> + if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ifm))) {
> + NL_SET_ERR_MSG(extack, "Invalid header");
> + return -EINVAL;
> + }
> +
> + if (nlh->nlmsg_len > nlmsg_msg_size(sizeof(*ifm))) {
> + NL_SET_ERR_MSG(extack, "Invalid data after header");
> + return -EINVAL;
> + }
> +
> + ifm = nlmsg_data(nlh);
> + if (ifm->__ifi_pad || ifm->ifi_type || ifm->ifi_flags ||
> + ifm->ifi_change || ifm->ifi_index) {
> + NL_SET_ERR_MSG(extack, "Invalid values in header for dump
> request");
> + return -EINVAL;
> + }
> +
> + return 0;
> +}
> +
> static int ipmr_rtm_dumplink(struct sk_buff *skb, struct netlink_callback
> *cb)
> {
> struct net *net = sock_net(skb->sk);
> @@ -2718,6 +2743,13 @@ static int ipmr_rtm_dumplink(struct sk_buff *skb,
> struct netlink_callback *cb)
> unsigned int e = 0, s_e;
> struct mr_table *mrt;
>
> + if (cb->strict_check) {
> + int err = ipmr_valid_dumplink(cb->nlh, cb->extack);
> +
> + if (err)
> + return err;
Nit: can we remove the unnecessary \n, please.
> + }
> +
> s_t = cb->args[0];
> s_e = cb->args[1];
>
> --
> 2.11.0
>
