From: Guillaume Nault <gnault@redhat.com>
Date: Mon, 23 Mar 2020 21:48:51 +0100
Subject: cls_flower: Add extack support for src and dst port range options
Patch-mainline: v5.7-rc1
Git-commit: bd7d4c12819b60b161939bc2f43053955d24d0df
References: bsc#1176447

Pass extack down to fl_set_key_port_range() and set message on error.

Both the min and max ports would qualify as invalid attributes here.
Report the min one as invalid, as it's probably what makes the most
sense from a user point of view.

Signed-off-by: Guillaume Nault <gnault@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Acked-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
 net/sched/cls_flower.c |   26 ++++++++++++++++++--------
 1 file changed, 18 insertions(+), 8 deletions(-)

--- a/net/sched/cls_flower.c
+++ b/net/sched/cls_flower.c
@@ -738,7 +738,8 @@ static void fl_set_key_val(struct nlattr
 }
 
 static int fl_set_key_port_range(struct nlattr **tb, struct fl_flow_key *key,
-				 struct fl_flow_key *mask)
+				 struct fl_flow_key *mask,
+				 struct netlink_ext_ack *extack)
 {
 	fl_set_key_val(tb, &key->tp_range.tp_min.dst,
 		       TCA_FLOWER_KEY_PORT_DST_MIN, &mask->tp_range.tp_min.dst,
@@ -753,13 +754,22 @@ static int fl_set_key_port_range(struct
 		       TCA_FLOWER_KEY_PORT_SRC_MAX, &mask->tp_range.tp_max.src,
 		       TCA_FLOWER_UNSPEC, sizeof(key->tp_range.tp_max.src));
 
-	if ((mask->tp_range.tp_min.dst && mask->tp_range.tp_max.dst &&
-	     htons(key->tp_range.tp_max.dst) <=
-		 htons(key->tp_range.tp_min.dst)) ||
-	    (mask->tp_range.tp_min.src && mask->tp_range.tp_max.src &&
-	     htons(key->tp_range.tp_max.src) <=
-		 htons(key->tp_range.tp_min.src)))
+	if (mask->tp_range.tp_min.dst && mask->tp_range.tp_max.dst &&
+	    htons(key->tp_range.tp_max.dst) <=
+	    htons(key->tp_range.tp_min.dst)) {
+		NL_SET_ERR_MSG_ATTR(extack,
+				    tb[TCA_FLOWER_KEY_PORT_DST_MIN],
+				    "Invalid destination port range (min must be strictly smaller than max)");
 		return -EINVAL;
+	}
+	if (mask->tp_range.tp_min.src && mask->tp_range.tp_max.src &&
+	    htons(key->tp_range.tp_max.src) <=
+	    htons(key->tp_range.tp_min.src)) {
+		NL_SET_ERR_MSG_ATTR(extack,
+				    tb[TCA_FLOWER_KEY_PORT_SRC_MIN],
+				    "Invalid source port range (min must be strictly smaller than max)");
+		return -EINVAL;
+	}
 
 	return 0;
 }
@@ -1402,7 +1412,7 @@ static int fl_set_key(struct net *net, s
 	if (key->basic.ip_proto == IPPROTO_TCP ||
 	    key->basic.ip_proto == IPPROTO_UDP ||
 	    key->basic.ip_proto == IPPROTO_SCTP) {
-		ret = fl_set_key_port_range(tb, key, mask);
+		ret = fl_set_key_port_range(tb, key, mask, extack);
 		if (ret)
 			return ret;
 	}