net/bridge: Update br_mdb_dump for strict data checking

Update br_mdb_dump for strict data checking. If the flag is set,
the dump request is expected to have a br_port_msg 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 <dsahern@gmail.com>
Acked-by: Christian Brauner <christian@brauner.io>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
David Ahern 2018-10-07 20:16:42 -07:00 committed by David S. Miller
parent addd383f5a
commit c77b93641e

View File

@ -162,6 +162,29 @@ out:
return err;
}
static int br_mdb_valid_dump_req(const struct nlmsghdr *nlh,
struct netlink_ext_ack *extack)
{
struct br_port_msg *bpm;
if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*bpm))) {
NL_SET_ERR_MSG_MOD(extack, "Invalid header for mdb dump request");
return -EINVAL;
}
bpm = nlmsg_data(nlh);
if (bpm->ifindex) {
NL_SET_ERR_MSG_MOD(extack, "Filtering by device index is not supported for mdb dump request");
return -EINVAL;
}
if (nlmsg_attrlen(nlh, sizeof(*bpm))) {
NL_SET_ERR_MSG(extack, "Invalid data after header in mdb dump request");
return -EINVAL;
}
return 0;
}
static int br_mdb_dump(struct sk_buff *skb, struct netlink_callback *cb)
{
struct net_device *dev;
@ -169,6 +192,13 @@ static int br_mdb_dump(struct sk_buff *skb, struct netlink_callback *cb)
struct nlmsghdr *nlh = NULL;
int idx = 0, s_idx;
if (cb->strict_check) {
int err = br_mdb_valid_dump_req(cb->nlh, cb->extack);
if (err < 0)
return err;
}
s_idx = cb->args[0];
rcu_read_lock();