net: Fill in extack for mpls lwt encap
Fill in extack for errors in build_state for mpls lwt encap including
passing extack to nla_get_labels and adding error messages for failures
in it.
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/mpls/af_mpls.c b/net/mpls/af_mpls.c
index 257ec66..f383095 100644
--- a/net/mpls/af_mpls.c
+++ b/net/mpls/af_mpls.c
@@ -728,8 +728,8 @@ static int mpls_nh_build(struct net *net, struct mpls_route *rt,
goto errout;
if (newdst) {
- err = nla_get_labels(newdst, max_labels,
- &nh->nh_labels, nh->nh_label);
+ err = nla_get_labels(newdst, max_labels, &nh->nh_labels,
+ nh->nh_label, NULL);
if (err)
goto errout;
}
@@ -782,7 +782,8 @@ static u8 mpls_count_nexthops(struct rtnexthop *rtnh, int len,
nla = nla_find(attrs, attrlen, RTA_NEWDST);
if (nla &&
- nla_get_labels(nla, MAX_NEW_LABELS, &n_labels, NULL) != 0)
+ nla_get_labels(nla, MAX_NEW_LABELS, &n_labels,
+ NULL, NULL) != 0)
return 0;
*max_labels = max_t(u8, *max_labels, n_labels);
@@ -1541,8 +1542,8 @@ int nla_put_labels(struct sk_buff *skb, int attrtype,
}
EXPORT_SYMBOL_GPL(nla_put_labels);
-int nla_get_labels(const struct nlattr *nla,
- u8 max_labels, u8 *labels, u32 label[])
+int nla_get_labels(const struct nlattr *nla, u8 max_labels, u8 *labels,
+ u32 label[], struct netlink_ext_ack *extack)
{
unsigned len = nla_len(nla);
struct mpls_shim_hdr *nla_label;
@@ -1553,13 +1554,18 @@ int nla_get_labels(const struct nlattr *nla,
/* len needs to be an even multiple of 4 (the label size). Number
* of labels is a u8 so check for overflow.
*/
- if (len & 3 || len / 4 > 255)
+ if (len & 3 || len / 4 > 255) {
+ NL_SET_ERR_MSG_ATTR(extack, nla,
+ "Invalid length for labels attribute");
return -EINVAL;
+ }
/* Limit the number of new labels allowed */
nla_labels = len/4;
- if (nla_labels > max_labels)
+ if (nla_labels > max_labels) {
+ NL_SET_ERR_MSG(extack, "Too many labels");
return -EINVAL;
+ }
/* when label == NULL, caller wants number of labels */
if (!label)
@@ -1574,8 +1580,29 @@ int nla_get_labels(const struct nlattr *nla,
/* Ensure the bottom of stack flag is properly set
* and ttl and tc are both clear.
*/
- if ((dec.bos != bos) || dec.ttl || dec.tc)
+ if (dec.ttl) {
+ NL_SET_ERR_MSG_ATTR(extack, nla,
+ "TTL in label must be 0");
return -EINVAL;
+ }
+
+ if (dec.tc) {
+ NL_SET_ERR_MSG_ATTR(extack, nla,
+ "Traffic class in label must be 0");
+ return -EINVAL;
+ }
+
+ if (dec.bos != bos) {
+ NL_SET_BAD_ATTR(extack, nla);
+ if (bos) {
+ NL_SET_ERR_MSG(extack,
+ "BOS bit must be set in first label");
+ } else {
+ NL_SET_ERR_MSG(extack,
+ "BOS bit can only be set in first label");
+ }
+ return -EINVAL;
+ }
switch (dec.label) {
case MPLS_LABEL_IMPLNULL:
@@ -1583,6 +1610,8 @@ int nla_get_labels(const struct nlattr *nla,
* assign and distribute, but which never
* actually appears in the encapsulation.
*/
+ NL_SET_ERR_MSG_ATTR(extack, nla,
+ "Implicit NULL Label (3) can not be used in encapsulation");
return -EINVAL;
}
@@ -1696,14 +1725,14 @@ static int rtm_to_route_config(struct sk_buff *skb, struct nlmsghdr *nlh,
case RTA_NEWDST:
if (nla_get_labels(nla, MAX_NEW_LABELS,
&cfg->rc_output_labels,
- cfg->rc_output_label))
+ cfg->rc_output_label, NULL))
goto errout;
break;
case RTA_DST:
{
u8 label_count;
if (nla_get_labels(nla, 1, &label_count,
- &cfg->rc_label))
+ &cfg->rc_label, NULL))
goto errout;
/* Reserved labels may not be set */
