1 files changed, 202 insertions, 154 deletions

diff --git a/net/sched/cls_fw.c b/net/sched/cls_fw.c
index 9b97172db84a..cdddc8695228 100644
--- a/net/sched/cls_fw.c
+++ b/net/sched/cls_fw.c
@@ -1,21 +1,13 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
 /*
  * net/sched/cls_fw.c	Classifier mapping ipchains' fwmark to traffic class.
  *
- *		This program is free software; you can redistribute it and/or
- *		modify it under the terms of the GNU General Public License
- *		as published by the Free Software Foundation; either version
- *		2 of the License, or (at your option) any later version.
- *
  * Authors:	Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
  *
  * Changes:
  * Karlis Peisenieks <karlis@mt.lv> : 990415 : fw_walk off by one
  * Karlis Peisenieks <karlis@mt.lv> : 990415 : fw_delete killed all the filter (and kernel).
  * Alex <alex@pilotsoft.com> : 2004xxyy: Added Action extension
- *
- * JHS: We should remove the CONFIG_NET_CLS_IND from here
- * eventually when the meta match extension is made available
- *
  */
 
 #include <linux/module.h>
@@ -28,72 +20,52 @@
 #include <net/netlink.h>
 #include <net/act_api.h>
 #include <net/pkt_cls.h>
+#include <net/sch_generic.h>
+#include <net/tc_wrapper.h>
 
-#define HTSIZE (PAGE_SIZE/sizeof(struct fw_filter *))
+#define HTSIZE 256
 
 struct fw_head {
-	struct fw_filter *ht[HTSIZE];
-	u32 mask;
+	u32			mask;
+	struct fw_filter __rcu	*ht[HTSIZE];
+	struct rcu_head		rcu;
 };
 
 struct fw_filter {
-	struct fw_filter	*next;
+	struct fw_filter __rcu	*next;
 	u32			id;
 	struct tcf_result	res;
-#ifdef CONFIG_NET_CLS_IND
-	char			indev[IFNAMSIZ];
-#endif /* CONFIG_NET_CLS_IND */
+	int			ifindex;
 	struct tcf_exts		exts;
+	struct tcf_proto	*tp;
+	struct rcu_work		rwork;
 };
 
-static const struct tcf_ext_map fw_ext_map = {
-	.action = TCA_FW_ACT,
-	.police = TCA_FW_POLICE
-};
-
-static inline int fw_hash(u32 handle)
+static u32 fw_hash(u32 handle)
 {
-	if (HTSIZE == 4096)
-		return ((handle >> 24) & 0xFFF) ^
-		       ((handle >> 12) & 0xFFF) ^
-		       (handle & 0xFFF);
-	else if (HTSIZE == 2048)
-		return ((handle >> 22) & 0x7FF) ^
-		       ((handle >> 11) & 0x7FF) ^
-		       (handle & 0x7FF);
-	else if (HTSIZE == 1024)
-		return ((handle >> 20) & 0x3FF) ^
-		       ((handle >> 10) & 0x3FF) ^
-		       (handle & 0x3FF);
-	else if (HTSIZE == 512)
-		return (handle >> 27) ^
-		       ((handle >> 18) & 0x1FF) ^
-		       ((handle >> 9) & 0x1FF) ^
-		       (handle & 0x1FF);
-	else if (HTSIZE == 256) {
-		u8 *t = (u8 *) &handle;
-		return t[0] ^ t[1] ^ t[2] ^ t[3];
-	} else
-		return handle & (HTSIZE - 1);
+	handle ^= (handle >> 16);
+	handle ^= (handle >> 8);
+	return handle % HTSIZE;
 }
 
-static int fw_classify(struct sk_buff *skb, const struct tcf_proto *tp,
-			  struct tcf_result *res)
+TC_INDIRECT_SCOPE int fw_classify(struct sk_buff *skb,
+				  const struct tcf_proto *tp,
+				  struct tcf_result *res)
 {
-	struct fw_head *head = (struct fw_head *)tp->root;
+	struct fw_head *head = rcu_dereference_bh(tp->root);
 	struct fw_filter *f;
 	int r;
 	u32 id = skb->mark;
 
 	if (head != NULL) {
 		id &= head->mask;
-		for (f = head->ht[fw_hash(id)]; f; f = f->next) {
+
+		for (f = rcu_dereference_bh(head->ht[fw_hash(id)]); f;
+		     f = rcu_dereference_bh(f->next)) {
 			if (f->id == id) {
 				*res = f->res;
-#ifdef CONFIG_NET_CLS_IND
-				if (!tcf_match_indev(skb, f->indev))
+				if (!tcf_match_indev(skb, f->ifindex))
 					continue;
-#endif /* CONFIG_NET_CLS_IND */
 				r = tcf_exts_exec(skb, &f->exts, res);
 				if (r < 0)
 					continue;
@@ -102,9 +74,11 @@ static int fw_classify(struct sk_buff *skb, const struct tcf_proto *tp,
 			}
 		}
 	} else {
-		/* old method */
+		struct Qdisc *q = tcf_block_q(tp->chain->block);
+
+		/* Old method: classify the packet using its skb mark. */
 		if (id && (TC_H_MAJ(id) == 0 ||
-			   !(TC_H_MAJ(id ^ tp->q->handle)))) {
+			   !(TC_H_MAJ(id ^ q->handle)))) {
 			res->classid = id;
 			res->class = 0;
 			return 0;
@@ -114,40 +88,51 @@ static int fw_classify(struct sk_buff *skb, const struct tcf_proto *tp,
 	return -1;
 }
 
-static unsigned long fw_get(struct tcf_proto *tp, u32 handle)
+static void *fw_get(struct tcf_proto *tp, u32 handle)
 {
-	struct fw_head *head = (struct fw_head *)tp->root;
+	struct fw_head *head = rtnl_dereference(tp->root);
 	struct fw_filter *f;
 
 	if (head == NULL)
-		return 0;
+		return NULL;
 
-	for (f = head->ht[fw_hash(handle)]; f; f = f->next) {
+	f = rtnl_dereference(head->ht[fw_hash(handle)]);
+	for (; f; f = rtnl_dereference(f->next)) {
 		if (f->id == handle)
-			return (unsigned long)f;
+			return f;
 	}
-	return 0;
-}
-
-static void fw_put(struct tcf_proto *tp, unsigned long f)
-{
+	return NULL;
 }
 
 static int fw_init(struct tcf_proto *tp)
 {
+	/* We don't allocate fw_head here, because in the old method
+	 * we don't need it at all.
+	 */
 	return 0;
 }
 
-static void fw_delete_filter(struct tcf_proto *tp, struct fw_filter *f)
+static void __fw_delete_filter(struct fw_filter *f)
 {
-	tcf_unbind_filter(tp, &f->res);
-	tcf_exts_destroy(tp, &f->exts);
+	tcf_exts_destroy(&f->exts);
+	tcf_exts_put_net(&f->exts);
 	kfree(f);
 }
 
-static void fw_destroy(struct tcf_proto *tp)
+static void fw_delete_filter_work(struct work_struct *work)
+{
+	struct fw_filter *f = container_of(to_rcu_work(work),
+					   struct fw_filter,
+					   rwork);
+	rtnl_lock();
+	__fw_delete_filter(f);
+	rtnl_unlock();
+}
+
+static void fw_destroy(struct tcf_proto *tp, bool rtnl_held,
+		       struct netlink_ext_ack *extack)
 {
-	struct fw_head *head = tp->root;
+	struct fw_head *head = rtnl_dereference(tp->root);
 	struct fw_filter *f;
 	int h;
 
@@ -155,34 +140,56 @@ static void fw_destroy(struct tcf_proto *tp)
 		return;
 
 	for (h = 0; h < HTSIZE; h++) {
-		while ((f = head->ht[h]) != NULL) {
-			head->ht[h] = f->next;
-			fw_delete_filter(tp, f);
+		while ((f = rtnl_dereference(head->ht[h])) != NULL) {
+			RCU_INIT_POINTER(head->ht[h],
+					 rtnl_dereference(f->next));
+			tcf_unbind_filter(tp, &f->res);
+			if (tcf_exts_get_net(&f->exts))
+				tcf_queue_work(&f->rwork, fw_delete_filter_work);
+			else
+				__fw_delete_filter(f);
 		}
 	}
-	kfree(head);
+	kfree_rcu(head, rcu);
 }
 
-static int fw_delete(struct tcf_proto *tp, unsigned long arg)
+static int fw_delete(struct tcf_proto *tp, void *arg, bool *last,
+		     bool rtnl_held, struct netlink_ext_ack *extack)
 {
-	struct fw_head *head = (struct fw_head *)tp->root;
-	struct fw_filter *f = (struct fw_filter *)arg;
-	struct fw_filter **fp;
+	struct fw_head *head = rtnl_dereference(tp->root);
+	struct fw_filter *f = arg;
+	struct fw_filter __rcu **fp;
+	struct fw_filter *pfp;
+	int ret = -EINVAL;
+	int h;
 
 	if (head == NULL || f == NULL)
 		goto out;
 
-	for (fp = &head->ht[fw_hash(f->id)]; *fp; fp = &(*fp)->next) {
-		if (*fp == f) {
-			tcf_tree_lock(tp);
-			*fp = f->next;
-			tcf_tree_unlock(tp);
-			fw_delete_filter(tp, f);
-			return 0;
+	fp = &head->ht[fw_hash(f->id)];
+
+	for (pfp = rtnl_dereference(*fp); pfp;
+	     fp = &pfp->next, pfp = rtnl_dereference(*fp)) {
+		if (pfp == f) {
+			RCU_INIT_POINTER(*fp, rtnl_dereference(f->next));
+			tcf_unbind_filter(tp, &f->res);
+			tcf_exts_get_net(&f->exts);
+			tcf_queue_work(&f->rwork, fw_delete_filter_work);
+			ret = 0;
+			break;
 		}
 	}
+
+	*last = true;
+	for (h = 0; h < HTSIZE; h++) {
+		if (rcu_access_pointer(head->ht[h])) {
+			*last = false;
+			break;
+		}
+	}
+
 out:
-	return -EINVAL;
+	return ret;
 }
 
 static const struct nla_policy fw_policy[TCA_FW_MAX + 1] = {
@@ -191,117 +198,154 @@ static const struct nla_policy fw_policy[TCA_FW_MAX + 1] = {
 	[TCA_FW_MASK]		= { .type = NLA_U32 },
 };
 
-static int
-fw_change_attrs(struct net *net, struct tcf_proto *tp, struct fw_filter *f,
-	struct nlattr **tb, struct nlattr **tca, unsigned long base)
+static int fw_set_parms(struct net *net, struct tcf_proto *tp,
+			struct fw_filter *f, struct nlattr **tb,
+			struct nlattr **tca, unsigned long base, u32 flags,
+			struct netlink_ext_ack *extack)
 {
-	struct fw_head *head = (struct fw_head *)tp->root;
-	struct tcf_exts e;
+	struct fw_head *head = rtnl_dereference(tp->root);
 	u32 mask;
 	int err;
 
-	err = tcf_exts_validate(net, tp, tb, tca[TCA_RATE], &e, &fw_ext_map);
+	err = tcf_exts_validate(net, tp, tb, tca[TCA_RATE], &f->exts, flags,
+				extack);
 	if (err < 0)
 		return err;
 
-	if (tb[TCA_FW_CLASSID]) {
-		f->res.classid = nla_get_u32(tb[TCA_FW_CLASSID]);
-		tcf_bind_filter(tp, &f->res, base);
-	}
-
-#ifdef CONFIG_NET_CLS_IND
 	if (tb[TCA_FW_INDEV]) {
-		err = tcf_change_indev(tp, f->indev, tb[TCA_FW_INDEV]);
-		if (err < 0)
-			goto errout;
+		int ret;
+		ret = tcf_change_indev(net, tb[TCA_FW_INDEV], extack);
+		if (ret < 0)
+			return ret;
+		f->ifindex = ret;
 	}
-#endif /* CONFIG_NET_CLS_IND */
 
 	err = -EINVAL;
 	if (tb[TCA_FW_MASK]) {
 		mask = nla_get_u32(tb[TCA_FW_MASK]);
 		if (mask != head->mask)
-			goto errout;
+			return err;
 	} else if (head->mask != 0xFFFFFFFF)
-		goto errout;
+		return err;
 
-	tcf_exts_change(tp, &f->exts, &e);
+	if (tb[TCA_FW_CLASSID]) {
+		f->res.classid = nla_get_u32(tb[TCA_FW_CLASSID]);
+		tcf_bind_filter(tp, &f->res, base);
+	}
 
 	return 0;
-errout:
-	tcf_exts_destroy(tp, &e);
-	return err;
 }
 
 static int fw_change(struct net *net, struct sk_buff *in_skb,
 		     struct tcf_proto *tp, unsigned long base,
-		     u32 handle,
-		     struct nlattr **tca,
-		     unsigned long *arg)
+		     u32 handle, struct nlattr **tca, void **arg,
+		     u32 flags, struct netlink_ext_ack *extack)
 {
-	struct fw_head *head = (struct fw_head *)tp->root;
-	struct fw_filter *f = (struct fw_filter *) *arg;
+	struct fw_head *head = rtnl_dereference(tp->root);
+	struct fw_filter *f = *arg;
 	struct nlattr *opt = tca[TCA_OPTIONS];
 	struct nlattr *tb[TCA_FW_MAX + 1];
 	int err;
 
 	if (!opt)
-		return handle ? -EINVAL : 0;
+		return handle ? -EINVAL : 0; /* Succeed if it is old method. */
 
-	err = nla_parse_nested(tb, TCA_FW_MAX, opt, fw_policy);
+	err = nla_parse_nested_deprecated(tb, TCA_FW_MAX, opt, fw_policy,
+					  NULL);
 	if (err < 0)
 		return err;
 
-	if (f != NULL) {
+	if (f) {
+		struct fw_filter *pfp, *fnew;
+		struct fw_filter __rcu **fp;
+
 		if (f->id != handle && handle)
 			return -EINVAL;
-		return fw_change_attrs(net, tp, f, tb, tca, base);
+
+		fnew = kzalloc(sizeof(struct fw_filter), GFP_KERNEL);
+		if (!fnew)
+			return -ENOBUFS;
+
+		fnew->id = f->id;
+		fnew->ifindex = f->ifindex;
+		fnew->tp = f->tp;
+
+		err = tcf_exts_init(&fnew->exts, net, TCA_FW_ACT,
+				    TCA_FW_POLICE);
+		if (err < 0) {
+			kfree(fnew);
+			return err;
+		}
+
+		err = fw_set_parms(net, tp, fnew, tb, tca, base, flags, extack);
+		if (err < 0) {
+			tcf_exts_destroy(&fnew->exts);
+			kfree(fnew);
+			return err;
+		}
+
+		fp = &head->ht[fw_hash(fnew->id)];
+		for (pfp = rtnl_dereference(*fp); pfp;
+		     fp = &pfp->next, pfp = rtnl_dereference(*fp))
+			if (pfp == f)
+				break;
+
+		RCU_INIT_POINTER(fnew->next, rtnl_dereference(pfp->next));
+		rcu_assign_pointer(*fp, fnew);
+		tcf_unbind_filter(tp, &f->res);
+		tcf_exts_get_net(&f->exts);
+		tcf_queue_work(&f->rwork, fw_delete_filter_work);
+
+		*arg = fnew;
+		return err;
 	}
 
 	if (!handle)
 		return -EINVAL;
 
-	if (head == NULL) {
+	if (!head) {
 		u32 mask = 0xFFFFFFFF;
 		if (tb[TCA_FW_MASK])
 			mask = nla_get_u32(tb[TCA_FW_MASK]);
 
-		head = kzalloc(sizeof(struct fw_head), GFP_KERNEL);
-		if (head == NULL)
+		head = kzalloc(sizeof(*head), GFP_KERNEL);
+		if (!head)
 			return -ENOBUFS;
 		head->mask = mask;
 
-		tcf_tree_lock(tp);
-		tp->root = head;
-		tcf_tree_unlock(tp);
+		rcu_assign_pointer(tp->root, head);
 	}
 
 	f = kzalloc(sizeof(struct fw_filter), GFP_KERNEL);
 	if (f == NULL)
 		return -ENOBUFS;
 
+	err = tcf_exts_init(&f->exts, net, TCA_FW_ACT, TCA_FW_POLICE);
+	if (err < 0)
+		goto errout;
 	f->id = handle;
+	f->tp = tp;
 
-	err = fw_change_attrs(net, tp, f, tb, tca, base);
+	err = fw_set_parms(net, tp, f, tb, tca, base, flags, extack);
 	if (err < 0)
 		goto errout;
 
-	f->next = head->ht[fw_hash(handle)];
-	tcf_tree_lock(tp);
-	head->ht[fw_hash(handle)] = f;
-	tcf_tree_unlock(tp);
+	RCU_INIT_POINTER(f->next, head->ht[fw_hash(handle)]);
+	rcu_assign_pointer(head->ht[fw_hash(handle)], f);
 
-	*arg = (unsigned long)f;
+	*arg = f;
 	return 0;
 
 errout:
+	tcf_exts_destroy(&f->exts);
 	kfree(f);
 	return err;
 }
 
-static void fw_walk(struct tcf_proto *tp, struct tcf_walker *arg)
+static void fw_walk(struct tcf_proto *tp, struct tcf_walker *arg,
+		    bool rtnl_held)
 {
-	struct fw_head *head = (struct fw_head *)tp->root;
+	struct fw_head *head = rtnl_dereference(tp->root);
 	int h;
 
 	if (head == NULL)
@@ -313,26 +357,19 @@ static void fw_walk(struct tcf_proto *tp, struct tcf_walker *arg)
 	for (h = 0; h < HTSIZE; h++) {
 		struct fw_filter *f;
 
-		for (f = head->ht[h]; f; f = f->next) {
-			if (arg->count < arg->skip) {
-				arg->count++;
-				continue;
-			}
-			if (arg->fn(tp, (unsigned long)f, arg) < 0) {
-				arg->stop = 1;
+		for (f = rtnl_dereference(head->ht[h]); f;
+		     f = rtnl_dereference(f->next)) {
+			if (!tc_cls_stats_dump(tp, arg, f))
 				return;
-			}
-			arg->count++;
 		}
 	}
 }
 
-static int fw_dump(struct tcf_proto *tp, unsigned long fh,
-		   struct sk_buff *skb, struct tcmsg *t)
+static int fw_dump(struct net *net, struct tcf_proto *tp, void *fh,
+		   struct sk_buff *skb, struct tcmsg *t, bool rtnl_held)
 {
-	struct fw_head *head = (struct fw_head *)tp->root;
-	struct fw_filter *f = (struct fw_filter *)fh;
-	unsigned char *b = skb_tail_pointer(skb);
+	struct fw_head *head = rtnl_dereference(tp->root);
+	struct fw_filter *f = fh;
 	struct nlattr *nest;
 
 	if (f == NULL)
@@ -340,53 +377,63 @@ static int fw_dump(struct tcf_proto *tp, unsigned long fh,
 
 	t->tcm_handle = f->id;
 
-	if (!f->res.classid && !tcf_exts_is_available(&f->exts))
+	if (!f->res.classid && !tcf_exts_has_actions(&f->exts))
 		return skb->len;
 
-	nest = nla_nest_start(skb, TCA_OPTIONS);
+	nest = nla_nest_start_noflag(skb, TCA_OPTIONS);
 	if (nest == NULL)
 		goto nla_put_failure;
 
 	if (f->res.classid &&
 	    nla_put_u32(skb, TCA_FW_CLASSID, f->res.classid))
 		goto nla_put_failure;
-#ifdef CONFIG_NET_CLS_IND
-	if (strlen(f->indev) &&
-	    nla_put_string(skb, TCA_FW_INDEV, f->indev))
-		goto nla_put_failure;
-#endif /* CONFIG_NET_CLS_IND */
+	if (f->ifindex) {
+		struct net_device *dev;
+		dev = __dev_get_by_index(net, f->ifindex);
+		if (dev && nla_put_string(skb, TCA_FW_INDEV, dev->name))
+			goto nla_put_failure;
+	}
 	if (head->mask != 0xFFFFFFFF &&
 	    nla_put_u32(skb, TCA_FW_MASK, head->mask))
 		goto nla_put_failure;
 
-	if (tcf_exts_dump(skb, &f->exts, &fw_ext_map) < 0)
+	if (tcf_exts_dump(skb, &f->exts) < 0)
 		goto nla_put_failure;
 
 	nla_nest_end(skb, nest);
 
-	if (tcf_exts_dump_stats(skb, &f->exts, &fw_ext_map) < 0)
+	if (tcf_exts_dump_stats(skb, &f->exts) < 0)
 		goto nla_put_failure;
 
 	return skb->len;
 
 nla_put_failure:
-	nlmsg_trim(skb, b);
+	nla_nest_cancel(skb, nest);
 	return -1;
 }
 
+static void fw_bind_class(void *fh, u32 classid, unsigned long cl, void *q,
+			  unsigned long base)
+{
+	struct fw_filter *f = fh;
+
+	tc_cls_bind_class(classid, cl, q, &f->res, base);
+}
+
 static struct tcf_proto_ops cls_fw_ops __read_mostly = {
 	.kind		=	"fw",
 	.classify	=	fw_classify,
 	.init		=	fw_init,
 	.destroy	=	fw_destroy,
 	.get		=	fw_get,
-	.put		=	fw_put,
 	.change		=	fw_change,
 	.delete		=	fw_delete,
 	.walk		=	fw_walk,
 	.dump		=	fw_dump,
+	.bind_class	=	fw_bind_class,
 	.owner		=	THIS_MODULE,
 };
+MODULE_ALIAS_NET_CLS("fw");
 
 static int __init init_fw(void)
 {
@@ -400,4 +447,5 @@ static void __exit exit_fw(void)
 
 module_init(init_fw)
 module_exit(exit_fw)
+MODULE_DESCRIPTION("SKB mark based TC classifier");
 MODULE_LICENSE("GPL");