1 files changed, 120 insertions, 51 deletions

diff --git a/net/sched/cls_api.c b/net/sched/cls_api.c
index ca5676b2668e..ecec0a1e1c1a 100644
--- a/net/sched/cls_api.c
+++ b/net/sched/cls_api.c
@@ -97,7 +97,7 @@ tcf_exts_miss_cookie_base_alloc(struct tcf_exts *exts, struct tcf_proto *tp,
 
 	err = xa_alloc_cyclic(&tcf_exts_miss_cookies_xa, &n->miss_cookie_base,
 			      n, xa_limit_32b, &next, GFP_KERNEL);
-	if (err)
+	if (err < 0)
 		goto err_xa_alloc;
 
 	exts->miss_cookie_node = n;
@@ -390,6 +390,7 @@ static struct tcf_proto *tcf_proto_create(const char *kind, u32 protocol,
 	tp->protocol = protocol;
 	tp->prio = prio;
 	tp->chain = chain;
+	tp->usesw = !tp->ops->reoffload;
 	spin_lock_init(&tp->lock);
 	refcount_set(&tp->refcnt, 1);
 
@@ -410,12 +411,40 @@ static void tcf_proto_get(struct tcf_proto *tp)
 	refcount_inc(&tp->refcnt);
 }
 
+static void tcf_proto_count_usesw(struct tcf_proto *tp, bool add)
+{
+#ifdef CONFIG_NET_CLS_ACT
+	struct tcf_block *block = tp->chain->block;
+	bool counted = false;
+
+	if (!add) {
+		if (tp->usesw && tp->counted) {
+			if (!atomic_dec_return(&block->useswcnt))
+				static_branch_dec(&tcf_sw_enabled_key);
+			tp->counted = false;
+		}
+		return;
+	}
+
+	spin_lock(&tp->lock);
+	if (tp->usesw && !tp->counted) {
+		counted = true;
+		tp->counted = true;
+	}
+	spin_unlock(&tp->lock);
+
+	if (counted && atomic_inc_return(&block->useswcnt) == 1)
+		static_branch_inc(&tcf_sw_enabled_key);
+#endif
+}
+
 static void tcf_chain_put(struct tcf_chain *chain);
 
 static void tcf_proto_destroy(struct tcf_proto *tp, bool rtnl_held,
 			      bool sig_destroy, struct netlink_ext_ack *extack)
 {
 	tp->ops->destroy(tp, rtnl_held, extack);
+	tcf_proto_count_usesw(tp, false);
 	if (sig_destroy)
 		tcf_proto_signal_destroyed(tp->chain, tp);
 	tcf_chain_put(tp->chain);
@@ -1482,6 +1511,7 @@ int tcf_block_get_ext(struct tcf_block **p_block, struct Qdisc *q,
 	return 0;
 
 err_dev_insert:
+	tcf_block_offload_unbind(block, q, ei);
 err_block_offload_bind:
 	tcf_chain0_head_change_cb_del(block, ei);
 err_chain0_head_change_cb_add:
@@ -1896,7 +1926,8 @@ static void tcf_chain_tp_remove(struct tcf_chain *chain,
 static struct tcf_proto *tcf_chain_tp_find(struct tcf_chain *chain,
 					   struct tcf_chain_info *chain_info,
 					   u32 protocol, u32 prio,
-					   bool prio_allocate);
+					   bool prio_allocate,
+					   struct netlink_ext_ack *extack);
 
 /* Try to insert new proto.
  * If proto with specified priority already exists, free new proto
@@ -1920,8 +1951,7 @@ static struct tcf_proto *tcf_chain_tp_insert_unique(struct tcf_chain *chain,
 		return ERR_PTR(-EAGAIN);
 	}
 
-	tp = tcf_chain_tp_find(chain, &chain_info,
-			       protocol, prio, false);
+	tp = tcf_chain_tp_find(chain, &chain_info, protocol, prio, false, NULL);
 	if (!tp)
 		err = tcf_chain_tp_insert(chain, &chain_info, tp_new);
 	mutex_unlock(&chain->filter_chain_lock);
@@ -1981,7 +2011,8 @@ static void tcf_chain_tp_delete_empty(struct tcf_chain *chain,
 static struct tcf_proto *tcf_chain_tp_find(struct tcf_chain *chain,
 					   struct tcf_chain_info *chain_info,
 					   u32 protocol, u32 prio,
-					   bool prio_allocate)
+					   bool prio_allocate,
+					   struct netlink_ext_ack *extack)
 {
 	struct tcf_proto **pprev;
 	struct tcf_proto *tp;
@@ -1992,9 +2023,14 @@ static struct tcf_proto *tcf_chain_tp_find(struct tcf_chain *chain,
 	     pprev = &tp->next) {
 		if (tp->prio >= prio) {
 			if (tp->prio == prio) {
-				if (prio_allocate ||
-				    (tp->protocol != protocol && protocol))
+				if (prio_allocate) {
+					NL_SET_ERR_MSG(extack, "Lowest ID from auto-alloc range already in use");
+					return ERR_PTR(-ENOSPC);
+				}
+				if (tp->protocol != protocol && protocol) {
+					NL_SET_ERR_MSG(extack, "Protocol mismatch for filter with specified priority");
 					return ERR_PTR(-EINVAL);
+				}
 			} else {
 				tp = NULL;
 			}
@@ -2021,6 +2057,7 @@ static int tcf_fill_node(struct net *net, struct sk_buff *skb,
 	struct tcmsg *tcm;
 	struct nlmsghdr  *nlh;
 	unsigned char *b = skb_tail_pointer(skb);
+	int ret = -EMSGSIZE;
 
 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*tcm), flags);
 	if (!nlh)
@@ -2065,11 +2102,45 @@ static int tcf_fill_node(struct net *net, struct sk_buff *skb,
 
 	return skb->len;
 
+cls_op_not_supp:
+	ret = -EOPNOTSUPP;
 out_nlmsg_trim:
 nla_put_failure:
-cls_op_not_supp:
 	nlmsg_trim(skb, b);
-	return -1;
+	return ret;
+}
+
+static struct sk_buff *tfilter_notify_prep(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,
+					   u32 portid, bool rtnl_held,
+					   struct netlink_ext_ack *extack)
+{
+	unsigned int size = oskb ? max(NLMSG_GOODSIZE, oskb->len) : NLMSG_GOODSIZE;
+	struct sk_buff *skb;
+	int ret;
+
+retry:
+	skb = alloc_skb(size, GFP_KERNEL);
+	if (!skb)
+		return ERR_PTR(-ENOBUFS);
+
+	ret = tcf_fill_node(net, skb, tp, block, q, parent, fh, portid,
+			    n->nlmsg_seq, n->nlmsg_flags, event, false,
+			    rtnl_held, extack);
+	if (ret <= 0) {
+		kfree_skb(skb);
+		if (ret == -EMSGSIZE) {
+			size += NLMSG_GOODSIZE;
+			goto retry;
+		}
+		return ERR_PTR(-EINVAL);
+	}
+	return skb;
 }
 
 static int tfilter_notify(struct net *net, struct sk_buff *oskb,
@@ -2085,16 +2156,10 @@ static int tfilter_notify(struct net *net, struct sk_buff *oskb,
 	if (!unicast && !rtnl_notify_needed(net, n->nlmsg_flags, RTNLGRP_TC))
 		return 0;
 
-	skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
-	if (!skb)
-		return -ENOBUFS;
-
-	if (tcf_fill_node(net, skb, tp, block, q, parent, fh, portid,
-			  n->nlmsg_seq, n->nlmsg_flags, event,
-			  false, rtnl_held, extack) <= 0) {
-		kfree_skb(skb);
-		return -EINVAL;
-	}
+	skb = tfilter_notify_prep(net, oskb, n, tp, block, q, parent, fh, event,
+				  portid, rtnl_held, extack);
+	if (IS_ERR(skb))
+		return PTR_ERR(skb);
 
 	if (unicast)
 		err = rtnl_unicast(skb, net, portid);
@@ -2117,16 +2182,11 @@ static int tfilter_del_notify(struct net *net, struct sk_buff *oskb,
 	if (!rtnl_notify_needed(net, n->nlmsg_flags, RTNLGRP_TC))
 		return tp->ops->delete(tp, fh, last, rtnl_held, extack);
 
-	skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
-	if (!skb)
-		return -ENOBUFS;
-
-	if (tcf_fill_node(net, skb, tp, block, q, parent, fh, portid,
-			  n->nlmsg_seq, n->nlmsg_flags, RTM_DELTFILTER,
-			  false, rtnl_held, extack) <= 0) {
+	skb = tfilter_notify_prep(net, oskb, n, tp, block, q, parent, fh,
+				  RTM_DELTFILTER, portid, rtnl_held, extack);
+	if (IS_ERR(skb)) {
 		NL_SET_ERR_MSG(extack, "Failed to build del event notification");
-		kfree_skb(skb);
-		return -EINVAL;
+		return PTR_ERR(skb);
 	}
 
 	err = tp->ops->delete(tp, fh, last, rtnl_held, extack);
@@ -2260,7 +2320,7 @@ replay:
 	}
 	block->classid = parent;
 
-	chain_index = tca[TCA_CHAIN] ? nla_get_u32(tca[TCA_CHAIN]) : 0;
+	chain_index = nla_get_u32_default(tca[TCA_CHAIN], 0);
 	if (chain_index > TC_ACT_EXT_VAL_MASK) {
 		NL_SET_ERR_MSG(extack, "Specified chain index exceeds upper limit");
 		err = -EINVAL;
@@ -2275,9 +2335,8 @@ replay:
 
 	mutex_lock(&chain->filter_chain_lock);
 	tp = tcf_chain_tp_find(chain, &chain_info, protocol,
-			       prio, prio_allocate);
+			       prio, prio_allocate, extack);
 	if (IS_ERR(tp)) {
-		NL_SET_ERR_MSG(extack, "Filter with specified priority/protocol not found");
 		err = PTR_ERR(tp);
 		goto errout_locked;
 	}
@@ -2367,6 +2426,7 @@ replay:
 		tfilter_notify(net, skb, n, tp, block, q, parent, fh,
 			       RTM_NEWTFILTER, false, rtnl_held, extack);
 		tfilter_put(tp, fh);
+		tcf_proto_count_usesw(tp, true);
 		/* q pointer is NULL for shared blocks */
 		if (q)
 			q->flags &= ~TCQ_F_CAN_BYPASS;
@@ -2471,7 +2531,7 @@ static int tc_del_tfilter(struct sk_buff *skb, struct nlmsghdr *n,
 		goto errout;
 	}
 
-	chain_index = tca[TCA_CHAIN] ? nla_get_u32(tca[TCA_CHAIN]) : 0;
+	chain_index = nla_get_u32_default(tca[TCA_CHAIN], 0);
 	if (chain_index > TC_ACT_EXT_VAL_MASK) {
 		NL_SET_ERR_MSG(extack, "Specified chain index exceeds upper limit");
 		err = -EINVAL;
@@ -2501,10 +2561,13 @@ static int tc_del_tfilter(struct sk_buff *skb, struct nlmsghdr *n,
 
 	mutex_lock(&chain->filter_chain_lock);
 	tp = tcf_chain_tp_find(chain, &chain_info, protocol,
-			       prio, false);
-	if (!tp || IS_ERR(tp)) {
+			       prio, false, extack);
+	if (!tp) {
+		err = -ENOENT;
 		NL_SET_ERR_MSG(extack, "Filter with specified priority/protocol not found");
-		err = tp ? PTR_ERR(tp) : -ENOENT;
+		goto errout_locked;
+	} else if (IS_ERR(tp)) {
+		err = PTR_ERR(tp);
 		goto errout_locked;
 	} else if (tca[TCA_KIND] && nla_strcmp(tca[TCA_KIND], tp->ops->kind)) {
 		NL_SET_ERR_MSG(extack, "Specified filter kind does not match existing one");
@@ -2626,7 +2689,7 @@ static int tc_get_tfilter(struct sk_buff *skb, struct nlmsghdr *n,
 		goto errout;
 	}
 
-	chain_index = tca[TCA_CHAIN] ? nla_get_u32(tca[TCA_CHAIN]) : 0;
+	chain_index = nla_get_u32_default(tca[TCA_CHAIN], 0);
 	if (chain_index > TC_ACT_EXT_VAL_MASK) {
 		NL_SET_ERR_MSG(extack, "Specified chain index exceeds upper limit");
 		err = -EINVAL;
@@ -2641,11 +2704,14 @@ static int tc_get_tfilter(struct sk_buff *skb, struct nlmsghdr *n,
 
 	mutex_lock(&chain->filter_chain_lock);
 	tp = tcf_chain_tp_find(chain, &chain_info, protocol,
-			       prio, false);
+			       prio, false, extack);
 	mutex_unlock(&chain->filter_chain_lock);
-	if (!tp || IS_ERR(tp)) {
+	if (!tp) {
+		err = -ENOENT;
 		NL_SET_ERR_MSG(extack, "Filter with specified priority/protocol not found");
-		err = tp ? PTR_ERR(tp) : -ENOENT;
+		goto errout;
+	} else if (IS_ERR(tp)) {
+		err = PTR_ERR(tp);
 		goto errout;
 	} else if (tca[TCA_KIND] && nla_strcmp(tca[TCA_KIND], tp->ops->kind)) {
 		NL_SET_ERR_MSG(extack, "Specified filter kind does not match existing one");
@@ -3066,7 +3132,7 @@ replay:
 	if (IS_ERR(block))
 		return PTR_ERR(block);
 
-	chain_index = tca[TCA_CHAIN] ? nla_get_u32(tca[TCA_CHAIN]) : 0;
+	chain_index = nla_get_u32_default(tca[TCA_CHAIN], 0);
 	if (chain_index > TC_ACT_EXT_VAL_MASK) {
 		NL_SET_ERR_MSG(extack, "Specified chain index exceeds upper limit");
 		err = -EINVAL;
@@ -4014,6 +4080,19 @@ static struct pernet_operations tcf_net_ops = {
 	.size = sizeof(struct tcf_net),
 };
 
+static const struct rtnl_msg_handler tc_filter_rtnl_msg_handlers[] __initconst = {
+	{.msgtype = RTM_NEWTFILTER, .doit = tc_new_tfilter,
+	 .flags = RTNL_FLAG_DOIT_UNLOCKED},
+	{.msgtype = RTM_DELTFILTER, .doit = tc_del_tfilter,
+	 .flags = RTNL_FLAG_DOIT_UNLOCKED},
+	{.msgtype = RTM_GETTFILTER, .doit = tc_get_tfilter,
+	 .dumpit = tc_dump_tfilter, .flags = RTNL_FLAG_DOIT_UNLOCKED},
+	{.msgtype = RTM_NEWCHAIN, .doit = tc_ctl_chain},
+	{.msgtype = RTM_DELCHAIN, .doit = tc_ctl_chain},
+	{.msgtype = RTM_GETCHAIN, .doit = tc_ctl_chain,
+	 .dumpit = tc_dump_chain},
+};
+
 static int __init tc_filter_init(void)
 {
 	int err;
@@ -4027,17 +4106,7 @@ static int __init tc_filter_init(void)
 		goto err_register_pernet_subsys;
 
 	xa_init_flags(&tcf_exts_miss_cookies_xa, XA_FLAGS_ALLOC1);
-
-	rtnl_register(PF_UNSPEC, RTM_NEWTFILTER, tc_new_tfilter, NULL,
-		      RTNL_FLAG_DOIT_UNLOCKED);
-	rtnl_register(PF_UNSPEC, RTM_DELTFILTER, tc_del_tfilter, NULL,
-		      RTNL_FLAG_DOIT_UNLOCKED);
-	rtnl_register(PF_UNSPEC, RTM_GETTFILTER, tc_get_tfilter,
-		      tc_dump_tfilter, RTNL_FLAG_DOIT_UNLOCKED);
-	rtnl_register(PF_UNSPEC, RTM_NEWCHAIN, tc_ctl_chain, NULL, 0);
-	rtnl_register(PF_UNSPEC, RTM_DELCHAIN, tc_ctl_chain, NULL, 0);
-	rtnl_register(PF_UNSPEC, RTM_GETCHAIN, tc_ctl_chain,
-		      tc_dump_chain, 0);
+	rtnl_register_many(tc_filter_rtnl_msg_handlers);
 
 	return 0;