net: Update netconf dump handlers for strict data checking
Update inet_netconf_dump_devconf, inet6_netconf_dump_devconf, and
mpls_netconf_dump_devconf for strict data checking. If the flag is set,
the dump request is expected to have an netconfmsg struct as the header.
The struct only has the family member 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>
diff --git a/net/mpls/af_mpls.c b/net/mpls/af_mpls.c
index 0458c8a..7f891ff 100644
--- a/net/mpls/af_mpls.c
+++ b/net/mpls/af_mpls.c
@@ -1263,6 +1263,7 @@ static int mpls_netconf_get_devconf(struct sk_buff *in_skb,
static int mpls_netconf_dump_devconf(struct sk_buff *skb,
struct netlink_callback *cb)
{
+ const struct nlmsghdr *nlh = cb->nlh;
struct net *net = sock_net(skb->sk);
struct hlist_head *head;
struct net_device *dev;
@@ -1270,6 +1271,21 @@ static int mpls_netconf_dump_devconf(struct sk_buff *skb,
int idx, s_idx;
int h, s_h;
+ if (cb->strict_check) {
+ struct netlink_ext_ack *extack = cb->extack;
+ struct netconfmsg *ncm;
+
+ if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ncm))) {
+ NL_SET_ERR_MSG_MOD(extack, "Invalid header for netconf dump request");
+ return -EINVAL;
+ }
+
+ if (nlmsg_attrlen(nlh, sizeof(*ncm))) {
+ NL_SET_ERR_MSG_MOD(extack, "Invalid data after header in netconf dump request");
+ return -EINVAL;
+ }
+ }
+
s_h = cb->args[0];
s_idx = idx = cb->args[1];
@@ -1286,7 +1302,7 @@ static int mpls_netconf_dump_devconf(struct sk_buff *skb,
goto cont;
if (mpls_netconf_fill_devconf(skb, mdev,
NETLINK_CB(cb->skb).portid,
- cb->nlh->nlmsg_seq,
+ nlh->nlmsg_seq,
RTM_NEWNETCONF,
NLM_F_MULTI,
NETCONFA_ALL) < 0) {
