1 files changed, 47 insertions, 30 deletions

diff --git a/net/sched/cls_api.c b/net/sched/cls_api.c
index 7b2aa04a7cdf..445ab1b0537d 100644
--- a/net/sched/cls_api.c
+++ b/net/sched/cls_api.c
@@ -41,8 +41,6 @@
 #include <net/tc_act/tc_gate.h>
 #include <net/flow_offload.h>
 
-extern const struct nla_policy rtm_tca_policy[TCA_MAX + 1];
-
 /* The list of all installed classifier types */
 static LIST_HEAD(tcf_proto_base);
 
@@ -487,7 +485,8 @@ static struct tcf_chain *tcf_chain_lookup_rcu(const struct tcf_block *block,
 #endif
 
 static int tc_chain_notify(struct tcf_chain *chain, struct sk_buff *oskb,
-			   u32 seq, u16 flags, int event, bool unicast);
+			   u32 seq, u16 flags, int event, bool unicast,
+			   struct netlink_ext_ack *extack);
 
 static struct tcf_chain *__tcf_chain_get(struct tcf_block *block,
 					 u32 chain_index, bool create,
@@ -520,7 +519,7 @@ static struct tcf_chain *__tcf_chain_get(struct tcf_block *block,
 	 */
 	if (is_first_reference && !by_act)
 		tc_chain_notify(chain, NULL, 0, NLM_F_CREATE | NLM_F_EXCL,
-				RTM_NEWCHAIN, false);
+				RTM_NEWCHAIN, false, NULL);
 
 	return chain;
 
@@ -553,8 +552,8 @@ static void __tcf_chain_put(struct tcf_chain *chain, bool by_act,
 {
 	struct tcf_block *block = chain->block;
 	const struct tcf_proto_ops *tmplt_ops;
+	unsigned int refcnt, non_act_refcnt;
 	bool free_block = false;
-	unsigned int refcnt;
 	void *tmplt_priv;
 
 	mutex_lock(&block->lock);
@@ -574,13 +573,15 @@ static void __tcf_chain_put(struct tcf_chain *chain, bool by_act,
 	 * save these to temporary variables.
 	 */
 	refcnt = --chain->refcnt;
+	non_act_refcnt = refcnt - chain->action_refcnt;
 	tmplt_ops = chain->tmplt_ops;
 	tmplt_priv = chain->tmplt_priv;
 
-	/* The last dropped non-action reference will trigger notification. */
-	if (refcnt - chain->action_refcnt == 0 && !by_act) {
-		tc_chain_notify_delete(tmplt_ops, tmplt_priv, chain->index,
-				       block, NULL, 0, 0, false);
+	if (non_act_refcnt == chain->explicitly_created && !by_act) {
+		if (non_act_refcnt == 0)
+			tc_chain_notify_delete(tmplt_ops, tmplt_priv,
+					       chain->index, block, NULL, 0, 0,
+					       false);
 		/* Last reference to chain, no need to lock. */
 		chain->flushing = false;
 	}
@@ -1817,7 +1818,8 @@ static int tcf_fill_node(struct net *net, struct sk_buff *skb,
 			 struct tcf_proto *tp, struct tcf_block *block,
 			 struct Qdisc *q, u32 parent, void *fh,
 			 u32 portid, u32 seq, u16 flags, int event,
-			 bool terse_dump, bool rtnl_held)
+			 bool terse_dump, bool rtnl_held,
+			 struct netlink_ext_ack *extack)
 {
 	struct tcmsg *tcm;
 	struct nlmsghdr  *nlh;
@@ -1857,7 +1859,13 @@ static int tcf_fill_node(struct net *net, struct sk_buff *skb,
 		    tp->ops->dump(net, tp, fh, skb, tcm, rtnl_held) < 0)
 			goto nla_put_failure;
 	}
+
+	if (extack && extack->_msg &&
+	    nla_put_string(skb, TCA_EXT_WARN_MSG, extack->_msg))
+		goto nla_put_failure;
+
 	nlh->nlmsg_len = skb_tail_pointer(skb) - b;
+
 	return skb->len;
 
 out_nlmsg_trim:
@@ -1871,7 +1879,7 @@ static int tfilter_notify(struct net *net, struct sk_buff *oskb,
 			  struct nlmsghdr *n, struct tcf_proto *tp,
 			  struct tcf_block *block, struct Qdisc *q,
 			  u32 parent, void *fh, int event, bool unicast,
-			  bool rtnl_held)
+			  bool rtnl_held, struct netlink_ext_ack *extack)
 {
 	struct sk_buff *skb;
 	u32 portid = oskb ? NETLINK_CB(oskb).portid : 0;
@@ -1883,7 +1891,7 @@ static int tfilter_notify(struct net *net, struct sk_buff *oskb,
 
 	if (tcf_fill_node(net, skb, tp, block, q, parent, fh, portid,
 			  n->nlmsg_seq, n->nlmsg_flags, event,
-			  false, rtnl_held) <= 0) {
+			  false, rtnl_held, extack) <= 0) {
 		kfree_skb(skb);
 		return -EINVAL;
 	}
@@ -1912,7 +1920,7 @@ static int tfilter_del_notify(struct net *net, struct sk_buff *oskb,
 
 	if (tcf_fill_node(net, skb, tp, block, q, parent, fh, portid,
 			  n->nlmsg_seq, n->nlmsg_flags, RTM_DELTFILTER,
-			  false, rtnl_held) <= 0) {
+			  false, rtnl_held, extack) <= 0) {
 		NL_SET_ERR_MSG(extack, "Failed to build del event notification");
 		kfree_skb(skb);
 		return -EINVAL;
@@ -1938,14 +1946,15 @@ static int tfilter_del_notify(struct net *net, struct sk_buff *oskb,
 static void tfilter_notify_chain(struct net *net, struct sk_buff *oskb,
 				 struct tcf_block *block, struct Qdisc *q,
 				 u32 parent, struct nlmsghdr *n,
-				 struct tcf_chain *chain, int event)
+				 struct tcf_chain *chain, int event,
+				 struct netlink_ext_ack *extack)
 {
 	struct tcf_proto *tp;
 
 	for (tp = tcf_get_next_proto(chain, NULL);
 	     tp; tp = tcf_get_next_proto(chain, tp))
-		tfilter_notify(net, oskb, n, tp, block,
-			       q, parent, NULL, event, false, true);
+		tfilter_notify(net, oskb, n, tp, block, q, parent, NULL,
+			       event, false, true, extack);
 }
 
 static void tfilter_put(struct tcf_proto *tp, void *fh)
@@ -2149,7 +2158,7 @@ replay:
 			      flags, extack);
 	if (err == 0) {
 		tfilter_notify(net, skb, n, tp, block, q, parent, fh,
-			       RTM_NEWTFILTER, false, rtnl_held);
+			       RTM_NEWTFILTER, false, rtnl_held, extack);
 		tfilter_put(tp, fh);
 		/* q pointer is NULL for shared blocks */
 		if (q)
@@ -2277,7 +2286,7 @@ static int tc_del_tfilter(struct sk_buff *skb, struct nlmsghdr *n,
 
 	if (prio == 0) {
 		tfilter_notify_chain(net, skb, block, q, parent, n,
-				     chain, RTM_DELTFILTER);
+				     chain, RTM_DELTFILTER, extack);
 		tcf_chain_flush(chain, rtnl_held);
 		err = 0;
 		goto errout;
@@ -2301,7 +2310,7 @@ static int tc_del_tfilter(struct sk_buff *skb, struct nlmsghdr *n,
 
 		tcf_proto_put(tp, rtnl_held, NULL);
 		tfilter_notify(net, skb, n, tp, block, q, parent, fh,
-			       RTM_DELTFILTER, false, rtnl_held);
+			       RTM_DELTFILTER, false, rtnl_held, extack);
 		err = 0;
 		goto errout;
 	}
@@ -2445,7 +2454,7 @@ static int tc_get_tfilter(struct sk_buff *skb, struct nlmsghdr *n,
 		err = -ENOENT;
 	} else {
 		err = tfilter_notify(net, skb, n, tp, block, q, parent,
-				     fh, RTM_NEWTFILTER, true, rtnl_held);
+				     fh, RTM_NEWTFILTER, true, rtnl_held, NULL);
 		if (err < 0)
 			NL_SET_ERR_MSG(extack, "Failed to send filter notify message");
 	}
@@ -2483,7 +2492,7 @@ static int tcf_node_dump(struct tcf_proto *tp, void *n, struct tcf_walker *arg)
 	return tcf_fill_node(net, a->skb, tp, a->block, a->q, a->parent,
 			     n, NETLINK_CB(a->cb->skb).portid,
 			     a->cb->nlh->nlmsg_seq, NLM_F_MULTI,
-			     RTM_NEWTFILTER, a->terse_dump, true);
+			     RTM_NEWTFILTER, a->terse_dump, true, NULL);
 }
 
 static bool tcf_chain_dump(struct tcf_chain *chain, struct Qdisc *q, u32 parent,
@@ -2517,7 +2526,7 @@ static bool tcf_chain_dump(struct tcf_chain *chain, struct Qdisc *q, u32 parent,
 			if (tcf_fill_node(net, skb, tp, block, q, parent, NULL,
 					  NETLINK_CB(cb->skb).portid,
 					  cb->nlh->nlmsg_seq, NLM_F_MULTI,
-					  RTM_NEWTFILTER, false, true) <= 0)
+					  RTM_NEWTFILTER, false, true, NULL) <= 0)
 				goto errout;
 			cb->args[1] = 1;
 		}
@@ -2660,7 +2669,8 @@ static int tc_chain_fill_node(const struct tcf_proto_ops *tmplt_ops,
 			      void *tmplt_priv, u32 chain_index,
 			      struct net *net, struct sk_buff *skb,
 			      struct tcf_block *block,
-			      u32 portid, u32 seq, u16 flags, int event)
+			      u32 portid, u32 seq, u16 flags, int event,
+			      struct netlink_ext_ack *extack)
 {
 	unsigned char *b = skb_tail_pointer(skb);
 	const struct tcf_proto_ops *ops;
@@ -2697,7 +2707,12 @@ static int tc_chain_fill_node(const struct tcf_proto_ops *tmplt_ops,
 			goto nla_put_failure;
 	}
 
+	if (extack && extack->_msg &&
+	    nla_put_string(skb, TCA_EXT_WARN_MSG, extack->_msg))
+		goto out_nlmsg_trim;
+
 	nlh->nlmsg_len = skb_tail_pointer(skb) - b;
+
 	return skb->len;
 
 out_nlmsg_trim:
@@ -2707,7 +2722,8 @@ nla_put_failure:
 }
 
 static int tc_chain_notify(struct tcf_chain *chain, struct sk_buff *oskb,
-			   u32 seq, u16 flags, int event, bool unicast)
+			   u32 seq, u16 flags, int event, bool unicast,
+			   struct netlink_ext_ack *extack)
 {
 	u32 portid = oskb ? NETLINK_CB(oskb).portid : 0;
 	struct tcf_block *block = chain->block;
@@ -2721,7 +2737,7 @@ static int tc_chain_notify(struct tcf_chain *chain, struct sk_buff *oskb,
 
 	if (tc_chain_fill_node(chain->tmplt_ops, chain->tmplt_priv,
 			       chain->index, net, skb, block, portid,
-			       seq, flags, event) <= 0) {
+			       seq, flags, event, extack) <= 0) {
 		kfree_skb(skb);
 		return -EINVAL;
 	}
@@ -2749,7 +2765,7 @@ static int tc_chain_notify_delete(const struct tcf_proto_ops *tmplt_ops,
 		return -ENOBUFS;
 
 	if (tc_chain_fill_node(tmplt_ops, tmplt_priv, chain_index, net, skb,
-			       block, portid, seq, flags, RTM_DELCHAIN) <= 0) {
+			       block, portid, seq, flags, RTM_DELCHAIN, NULL) <= 0) {
 		kfree_skb(skb);
 		return -EINVAL;
 	}
@@ -2782,6 +2798,7 @@ static int tc_chain_tmplt_add(struct tcf_chain *chain, struct net *net,
 		return PTR_ERR(ops);
 	if (!ops->tmplt_create || !ops->tmplt_destroy || !ops->tmplt_dump) {
 		NL_SET_ERR_MSG(extack, "Chain templates are not supported with specified classifier");
+		module_put(ops->owner);
 		return -EOPNOTSUPP;
 	}
 
@@ -2901,11 +2918,11 @@ replay:
 		}
 
 		tc_chain_notify(chain, NULL, 0, NLM_F_CREATE | NLM_F_EXCL,
-				RTM_NEWCHAIN, false);
+				RTM_NEWCHAIN, false, extack);
 		break;
 	case RTM_DELCHAIN:
 		tfilter_notify_chain(net, skb, block, q, parent, n,
-				     chain, RTM_DELTFILTER);
+				     chain, RTM_DELTFILTER, extack);
 		/* Flush the chain first as the user requested chain removal. */
 		tcf_chain_flush(chain, true);
 		/* In case the chain was successfully deleted, put a reference
@@ -2915,7 +2932,7 @@ replay:
 		break;
 	case RTM_GETCHAIN:
 		err = tc_chain_notify(chain, skb, n->nlmsg_seq,
-				      n->nlmsg_flags, n->nlmsg_type, true);
+				      n->nlmsg_flags, n->nlmsg_type, true, extack);
 		if (err < 0)
 			NL_SET_ERR_MSG(extack, "Failed to send chain notify message");
 		break;
@@ -3015,7 +3032,7 @@ static int tc_dump_chain(struct sk_buff *skb, struct netlink_callback *cb)
 					 chain->index, net, skb, block,
 					 NETLINK_CB(cb->skb).portid,
 					 cb->nlh->nlmsg_seq, NLM_F_MULTI,
-					 RTM_NEWCHAIN);
+					 RTM_NEWCHAIN, NULL);
 		if (err <= 0)
 			break;
 		index++;