1 files changed, 80 insertions, 12 deletions

diff --git a/net/mpls/af_mpls.c b/net/mpls/af_mpls.c
index 5fe274c47c41..7d55d4c04088 100644
--- a/net/mpls/af_mpls.c
+++ b/net/mpls/af_mpls.c
@@ -2032,16 +2032,21 @@ nla_put_failure:
 }
 
 #if IS_ENABLED(CONFIG_INET)
-static int mpls_valid_fib_dump_req(const struct nlmsghdr *nlh,
-				   struct netlink_ext_ack *extack)
+static int mpls_valid_fib_dump_req(struct net *net, const struct nlmsghdr *nlh,
+				   struct fib_dump_filter *filter,
+				   struct netlink_callback *cb)
 {
-	return ip_valid_fib_dump_req(nlh, extack);
+	return ip_valid_fib_dump_req(net, nlh, filter, cb);
 }
 #else
-static int mpls_valid_fib_dump_req(const struct nlmsghdr *nlh,
-				   struct netlink_ext_ack *extack)
+static int mpls_valid_fib_dump_req(struct net *net, const struct nlmsghdr *nlh,
+				   struct fib_dump_filter *filter,
+				   struct netlink_callback *cb)
 {
+	struct netlink_ext_ack *extack = cb->extack;
+	struct nlattr *tb[RTA_MAX + 1];
 	struct rtmsg *rtm;
+	int err, i;
 
 	if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*rtm))) {
 		NL_SET_ERR_MSG_MOD(extack, "Invalid header for FIB dump request");
@@ -2050,36 +2055,90 @@ static int mpls_valid_fib_dump_req(const struct nlmsghdr *nlh,
 
 	rtm = nlmsg_data(nlh);
 	if (rtm->rtm_dst_len || rtm->rtm_src_len  || rtm->rtm_tos   ||
-	    rtm->rtm_table   || rtm->rtm_protocol || rtm->rtm_scope ||
-	    rtm->rtm_type    || rtm->rtm_flags) {
+	    rtm->rtm_table   || rtm->rtm_scope    || rtm->rtm_type  ||
+	    rtm->rtm_flags) {
 		NL_SET_ERR_MSG_MOD(extack, "Invalid values in header for FIB dump request");
 		return -EINVAL;
 	}
 
-	if (nlmsg_attrlen(nlh, sizeof(*rtm))) {
-		NL_SET_ERR_MSG_MOD(extack, "Invalid data after header in FIB dump request");
-		return -EINVAL;
+	if (rtm->rtm_protocol) {
+		filter->protocol = rtm->rtm_protocol;
+		filter->filter_set = 1;
+		cb->answer_flags = NLM_F_DUMP_FILTERED;
+	}
+
+	err = nlmsg_parse_strict(nlh, sizeof(*rtm), tb, RTA_MAX,
+				 rtm_mpls_policy, extack);
+	if (err < 0)
+		return err;
+
+	for (i = 0; i <= RTA_MAX; ++i) {
+		int ifindex;
+
+		if (i == RTA_OIF) {
+			ifindex = nla_get_u32(tb[i]);
+			filter->dev = __dev_get_by_index(net, ifindex);
+			if (!filter->dev)
+				return -ENODEV;
+			filter->filter_set = 1;
+		} else if (tb[i]) {
+			NL_SET_ERR_MSG_MOD(extack, "Unsupported attribute in dump request");
+			return -EINVAL;
+		}
 	}
 
 	return 0;
 }
 #endif
 
+static bool mpls_rt_uses_dev(struct mpls_route *rt,
+			     const struct net_device *dev)
+{
+	struct net_device *nh_dev;
+
+	if (rt->rt_nhn == 1) {
+		struct mpls_nh *nh = rt->rt_nh;
+
+		nh_dev = rtnl_dereference(nh->nh_dev);
+		if (dev == nh_dev)
+			return true;
+	} else {
+		for_nexthops(rt) {
+			nh_dev = rtnl_dereference(nh->nh_dev);
+			if (nh_dev == dev)
+				return true;
+		} endfor_nexthops(rt);
+	}
+
+	return false;
+}
+
 static int mpls_dump_routes(struct sk_buff *skb, struct netlink_callback *cb)
 {
 	const struct nlmsghdr *nlh = cb->nlh;
 	struct net *net = sock_net(skb->sk);
 	struct mpls_route __rcu **platform_label;
+	struct fib_dump_filter filter = {};
+	unsigned int flags = NLM_F_MULTI;
 	size_t platform_labels;
 	unsigned int index;
 
 	ASSERT_RTNL();
 
 	if (cb->strict_check) {
-		int err = mpls_valid_fib_dump_req(nlh, cb->extack);
+		int err;
 
+		err = mpls_valid_fib_dump_req(net, nlh, &filter, cb);
 		if (err < 0)
 			return err;
+
+		/* for MPLS, there is only 1 table with fixed type and flags.
+		 * If either are set in the filter then return nothing.
+		 */
+		if ((filter.table_id && filter.table_id != RT_TABLE_MAIN) ||
+		    (filter.rt_type && filter.rt_type != RTN_UNICAST) ||
+		     filter.flags)
+			return skb->len;
 	}
 
 	index = cb->args[0];
@@ -2088,15 +2147,24 @@ static int mpls_dump_routes(struct sk_buff *skb, struct netlink_callback *cb)
 
 	platform_label = rtnl_dereference(net->mpls.platform_label);
 	platform_labels = net->mpls.platform_labels;
+
+	if (filter.filter_set)
+		flags |= NLM_F_DUMP_FILTERED;
+
 	for (; index < platform_labels; index++) {
 		struct mpls_route *rt;
+
 		rt = rtnl_dereference(platform_label[index]);
 		if (!rt)
 			continue;
 
+		if ((filter.dev && !mpls_rt_uses_dev(rt, filter.dev)) ||
+		    (filter.protocol && rt->rt_protocol != filter.protocol))
+			continue;
+
 		if (mpls_dump_route(skb, NETLINK_CB(cb->skb).portid,
 				    cb->nlh->nlmsg_seq, RTM_NEWROUTE,
-				    index, rt, NLM_F_MULTI) < 0)
+				    index, rt, flags) < 0)
 			break;
 	}
 	cb->args[0] = index;