Subject: Re: [PATCH net-next v3 2/6] net_sched: act: use standard struct list_head

From: Jamal Hadi Salim <[email-masked]>
Date: Fri, 13 Dec 2013 07:08:43 -0500

On 12/13/13 00:47, Cong Wang wrote:
> Currently actions are chained by a singly linked list,
> therefore it is a bit hard to add and remove a specific
> entry. Convert it to struct list_head so that in the
> latter patch we can remove an action without finding
> its head.
>

Looks reasonable - but can you find a more usable noun
than "head"?

cheers,
jamal
> Cc: Jamal Hadi Salim <[email-masked]>
> Cc: David S. Miller <[email-masked]>
> Signed-off-by: Cong Wang <[email-masked]>
> ---
>   include/net/act_api.h   |  12 +++---
>   include/net/pkt_cls.h   |  15 +++++--
>   net/sched/act_api.c     | 105 +++++++++++++++++++++---------------------------
>   net/sched/cls_api.c     |  54 ++++++++++++-------------
>   net/sched/cls_basic.c   |   1 +
>   net/sched/cls_bpf.c     |   1 +
>   net/sched/cls_cgroup.c  |   1 +
>   net/sched/cls_flow.c    |   1 +
>   net/sched/cls_fw.c      |   1 +
>   net/sched/cls_route.c   |   1 +
>   net/sched/cls_rsvp.h    |   1 +
>   net/sched/cls_tcindex.c |   5 ++-
>   net/sched/cls_u32.c     |   1 +
>   13 files changed, 100 insertions(+), 99 deletions(-)
>
> diff --git a/include/net/act_api.h b/include/net/act_api.h
> index 04c6825..ebaf4b5 100644
> --- a/include/net/act_api.h
> +++ b/include/net/act_api.h
> @@ -60,7 +60,7 @@ struct tc_action {
>   	const struct tc_action_ops	*ops;
>   	__u32			type; /* for backward compat(TCA_OLD_COMPAT) */
>   	__u32			order;
> -	struct tc_action	*next;
> +	struct list_head	list;
>   };
>
>   #define TCA_CAP_NONE 0
> @@ -99,16 +99,16 @@ void tcf_hash_insert(struct tcf_common *p, struct tcf_hashinfo *hinfo);
>
>   int tcf_register_action(struct tc_action_ops *a);
>   int tcf_unregister_action(struct tc_action_ops *a);
> -void tcf_action_destroy(struct tc_action *a, int bind);
> -int tcf_action_exec(struct sk_buff *skb, const struct tc_action *a,
> +void tcf_action_destroy(struct list_head *head, int bind);
> +int tcf_action_exec(struct sk_buff *skb, const struct list_head *head,
>   		    struct tcf_result *res);
> -struct tc_action *tcf_action_init(struct net *net, struct nlattr *nla,
> +int tcf_action_init(struct net *net, struct nlattr *nla,
>   				  struct nlattr *est, char *n, int ovr,
> -				  int bind);
> +				  int bind, struct list_head *);
>   struct tc_action *tcf_action_init_1(struct net *net, struct nlattr *nla,
>   				    struct nlattr *est, char *n, int ovr,
>   				    int bind);
> -int tcf_action_dump(struct sk_buff *skb, struct tc_action *a, int, int);
> +int tcf_action_dump(struct sk_buff *skb, struct list_head *, int, int);
>   int tcf_action_dump_old(struct sk_buff *skb, struct tc_action *a, int, int);
>   int tcf_action_dump_1(struct sk_buff *skb, struct tc_action *a, int, int);
>   int tcf_action_copy_stats(struct sk_buff *, struct tc_action *, int);
> diff --git a/include/net/pkt_cls.h b/include/net/pkt_cls.h
> index 2ebef77..a85264b 100644
> --- a/include/net/pkt_cls.h
> +++ b/include/net/pkt_cls.h
> @@ -62,7 +62,8 @@ tcf_unbind_filter(struct tcf_proto *tp, struct tcf_result *r)
>
>   struct tcf_exts {
>   #ifdef CONFIG_NET_CLS_ACT
> -	struct tc_action *action;
> +	__u32	type; /* for backward compat(TCA_OLD_COMPAT) */
> +	struct list_head head;
>   #endif
>   };
>
> @@ -85,12 +86,18 @@ static inline int
>   tcf_exts_is_predicative(struct tcf_exts *exts)
>   {
>   #ifdef CONFIG_NET_CLS_ACT
> -	return !!exts->action;
> +	return list_empty(&exts->head);
>   #else
>   	return 0;
>   #endif
>   }
>
> +static inline void tcf_exts_init(struct tcf_exts *exts)
> +{
> +#ifdef CONFIG_NET_CLS_ACT
> +	INIT_LIST_HEAD(&exts->head);
> +#endif
> +}
>   /**
>    * tcf_exts_is_available - check if at least one extension is present
>    * @exts: tc filter extensions handle
> @@ -120,8 +127,8 @@ tcf_exts_exec(struct sk_buff *skb, struct tcf_exts *exts,
>   	       struct tcf_result *res)
>   {
>   #ifdef CONFIG_NET_CLS_ACT
> -	if (exts->action)
> -		return tcf_action_exec(skb, exts->action, res);
> +	if (!list_empty(&exts->head))
> +		return tcf_action_exec(skb, &exts->head, res);
>   #endif
>   	return 0;
>   }
> diff --git a/net/sched/act_api.c b/net/sched/act_api.c
> index 51e28f7..88b5087 100644
> --- a/net/sched/act_api.c
> +++ b/net/sched/act_api.c
> @@ -379,7 +379,7 @@ static struct tc_action_ops *tc_lookup_action_id(u32 type)
>   }
>   #endif
>
> -int tcf_action_exec(struct sk_buff *skb, const struct tc_action *act,
> +int tcf_action_exec(struct sk_buff *skb, const struct list_head *head,
>   		    struct tcf_result *res)
>   {
>   	const struct tc_action *a;
> @@ -390,7 +390,7 @@ int tcf_action_exec(struct sk_buff *skb, const struct tc_action *act,
>   		ret = TC_ACT_OK;
>   		goto exec_done;
>   	}
> -	while ((a = act) != NULL) {
> +	list_for_each_entry(a, head, list) {
>   repeat:
>   		if (a->ops) {
>   			ret = a->ops->act(skb, a, res);
> @@ -404,27 +404,26 @@ repeat:
>   			if (ret != TC_ACT_PIPE)
>   				goto exec_done;
>   		}
> -		act = a->next;
>   	}
>   exec_done:
>   	return ret;
>   }
>   EXPORT_SYMBOL(tcf_action_exec);
>
> -void tcf_action_destroy(struct tc_action *act, int bind)
> +void tcf_action_destroy(struct list_head *head, int bind)
>   {
> -	struct tc_action *a;
> +	struct tc_action *a, *tmp;
>
> -	for (a = act; a; a = act) {
> +	list_for_each_entry_safe(a, tmp, head, list) {
>   		if (a->ops) {
>   			if (a->ops->cleanup(a, bind) == ACT_P_DELETED)
>   				module_put(a->ops->owner);
> -			act = act->next;
> +			list_del(&a->list);
>   			kfree(a);
>   		} else {
>   			/*FIXME: Remove later - catch insertion bugs*/
>   			WARN(1, "tcf_action_destroy: BUG? destroying NULL ops\n");
> -			act = act->next;
> +			list_del(&a->list);
>   			kfree(a);
>   		}
>   	}
> @@ -470,14 +469,13 @@ nla_put_failure:
>   EXPORT_SYMBOL(tcf_action_dump_1);
>
>   int
> -tcf_action_dump(struct sk_buff *skb, struct tc_action *act, int bind, int ref)
> +tcf_action_dump(struct sk_buff *skb, struct list_head *head, int bind, int ref)
>   {
>   	struct tc_action *a;
>   	int err = -EINVAL;
>   	struct nlattr *nest;
>
> -	while ((a = act) != NULL) {
> -		act = a->next;
> +	list_for_each_entry(a, head, list) {
>   		nest = nla_nest_start(skb, a->order);
>   		if (nest == NULL)
>   			goto nla_put_failure;
> @@ -552,6 +550,7 @@ struct tc_action *tcf_action_init_1(struct net *net, struct nlattr *nla,
>   	if (a == NULL)
>   		goto err_mod;
>
> +	INIT_LIST_HEAD(&a->list);
>   	/* backward compatibility for policer */
>   	if (name == NULL)
>   		err = a_o->init(net, tb[TCA_ACT_OPTIONS], est, a, ovr, bind);
> @@ -578,37 +577,33 @@ err_out:
>   	return ERR_PTR(err);
>   }
>
> -struct tc_action *tcf_action_init(struct net *net, struct nlattr *nla,
> +int tcf_action_init(struct net *net, struct nlattr *nla,
>   				  struct nlattr *est, char *name, int ovr,
> -				  int bind)
> +				  int bind, struct list_head *head)
>   {
>   	struct nlattr *tb[TCA_ACT_MAX_PRIO + 1];
> -	struct tc_action *head = NULL, *act, *act_prev = NULL;
> +	struct tc_action *act;
>   	int err;
>   	int i;
>
>   	err = nla_parse_nested(tb, TCA_ACT_MAX_PRIO, nla, NULL);
>   	if (err < 0)
> -		return ERR_PTR(err);
> +		return err;
>
>   	for (i = 1; i <= TCA_ACT_MAX_PRIO && tb[i]; i++) {
>   		act = tcf_action_init_1(net, tb[i], est, name, ovr, bind);
> -		if (IS_ERR(act))
> +		if (IS_ERR(act)) {
> +			err = PTR_ERR(act);
>   			goto err;
> +		}
>   		act->order = i;
> -
> -		if (head == NULL)
> -			head = act;
> -		else
> -			act_prev->next = act;
> -		act_prev = act;
> +		list_add_tail(&act->list, head);
>   	}
> -	return head;
> +	return 0;
>
>   err:
> -	if (head != NULL)
> -		tcf_action_destroy(head, bind);
> -	return act;
> +	tcf_action_destroy(head, bind);
> +	return err;
>   }
>
>   int tcf_action_copy_stats(struct sk_buff *skb, struct tc_action *a,
> @@ -653,7 +648,7 @@ errout:
>   }
>
>   static int
> -tca_get_fill(struct sk_buff *skb, struct tc_action *a, u32 portid, u32 seq,
> +tca_get_fill(struct sk_buff *skb, struct list_head *head, u32 portid, u32 seq,
>   	     u16 flags, int event, int bind, int ref)
>   {
>   	struct tcamsg *t;
> @@ -673,7 +668,7 @@ tca_get_fill(struct sk_buff *skb, struct tc_action *a, u32 portid, u32 seq,
>   	if (nest == NULL)
>   		goto out_nlmsg_trim;
>
> -	if (tcf_action_dump(skb, a, bind, ref) < 0)
> +	if (tcf_action_dump(skb, head, bind, ref) < 0)
>   		goto out_nlmsg_trim;
>
>   	nla_nest_end(skb, nest);
> @@ -688,14 +683,14 @@ out_nlmsg_trim:
>
>   static int
>   act_get_notify(struct net *net, u32 portid, struct nlmsghdr *n,
> -	       struct tc_action *a, int event)
> +	       struct list_head *head, int event)
>   {
>   	struct sk_buff *skb;
>
>   	skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
>   	if (!skb)
>   		return -ENOBUFS;
> -	if (tca_get_fill(skb, a, portid, n->nlmsg_seq, 0, event, 0, 0) <= 0) {
> +	if (tca_get_fill(skb, head, portid, n->nlmsg_seq, 0, event, 0, 0) <= 0) {
>   		kfree_skb(skb);
>   		return -EINVAL;
>   	}
> @@ -726,6 +721,7 @@ tcf_action_get_1(struct nlattr *nla, struct nlmsghdr *n, u32 portid)
>   	if (a == NULL)
>   		goto err_out;
>
> +	INIT_LIST_HEAD(&a->list);
>   	err = -EINVAL;
>   	a->ops = tc_lookup_action(tb[TCA_ACT_KIND]);
>   	if (a->ops == NULL)
> @@ -745,12 +741,12 @@ err_out:
>   	return ERR_PTR(err);
>   }
>
> -static void cleanup_a(struct tc_action *act)
> +static void cleanup_a(struct list_head *head)
>   {
> -	struct tc_action *a;
> +	struct tc_action *a, *tmp;
>
> -	for (a = act; a; a = act) {
> -		act = a->next;
> +	list_for_each_entry_safe(a, tmp, head, list) {
> +		list_del(&a->list);
>   		kfree(a);
>   	}
>   }
> @@ -765,6 +761,7 @@ static struct tc_action *create_a(int i)
>   		return NULL;
>   	}
>   	act->order = i;
> +	INIT_LIST_HEAD(&act->list);
>   	return act;
>   }
>
> @@ -852,7 +849,8 @@ tca_action_gd(struct net *net, struct nlattr *nla, struct nlmsghdr *n,
>   {
>   	int i, ret;
>   	struct nlattr *tb[TCA_ACT_MAX_PRIO + 1];
> -	struct tc_action *head = NULL, *act, *act_prev = NULL;
> +	struct tc_action *act;
> +	LIST_HEAD(head);
>
>   	ret = nla_parse_nested(tb, TCA_ACT_MAX_PRIO, nla, NULL);
>   	if (ret < 0)
> @@ -872,16 +870,11 @@ tca_action_gd(struct net *net, struct nlattr *nla, struct nlmsghdr *n,
>   			goto err;
>   		}
>   		act->order = i;
> -
> -		if (head == NULL)
> -			head = act;
> -		else
> -			act_prev->next = act;
> -		act_prev = act;
> +		list_add_tail(&act->list, &head);
>   	}
>
>   	if (event == RTM_GETACTION)
> -		ret = act_get_notify(net, portid, n, head, event);
> +		ret = act_get_notify(net, portid, n, &head, event);
>   	else { /* delete */
>   		struct sk_buff *skb;
>
> @@ -891,7 +884,7 @@ tca_action_gd(struct net *net, struct nlattr *nla, struct nlmsghdr *n,
>   			goto err;
>   		}
>
> -		if (tca_get_fill(skb, head, portid, n->nlmsg_seq, 0, event,
> +		if (tca_get_fill(skb, &head, portid, n->nlmsg_seq, 0, event,
>   				 0, 1) <= 0) {
>   			kfree_skb(skb);
>   			ret = -EINVAL;
> @@ -899,7 +892,7 @@ tca_action_gd(struct net *net, struct nlattr *nla, struct nlmsghdr *n,
>   		}
>
>   		/* now do the delete */
> -		tcf_action_destroy(head, 0);
> +		tcf_action_destroy(&head, 0);
>   		ret = rtnetlink_send(skb, net, portid, RTNLGRP_TC,
>   				     n->nlmsg_flags & NLM_F_ECHO);
>   		if (ret > 0)
> @@ -907,11 +900,11 @@ tca_action_gd(struct net *net, struct nlattr *nla, struct nlmsghdr *n,
>   		return ret;
>   	}
>   err:
> -	cleanup_a(head);
> +	cleanup_a(&head);
>   	return ret;
>   }
>
> -static int tcf_add_notify(struct net *net, struct tc_action *a,
> +static int tcf_add_notify(struct net *net, struct list_head *head,
>   			  u32 portid, u32 seq, int event, u16 flags)
>   {
>   	struct tcamsg *t;
> @@ -939,7 +932,7 @@ static int tcf_add_notify(struct net *net, struct tc_action *a,
>   	if (nest == NULL)
>   		goto out_kfree_skb;
>
> -	if (tcf_action_dump(skb, a, 0, 0) < 0)
> +	if (tcf_action_dump(skb, head, 0, 0) < 0)
>   		goto out_kfree_skb;
>
>   	nla_nest_end(skb, nest);
> @@ -963,26 +956,18 @@ tcf_action_add(struct net *net, struct nlattr *nla, struct nlmsghdr *n,
>   	       u32 portid, int ovr)
>   {
>   	int ret = 0;
> -	struct tc_action *act;
> -	struct tc_action *a;
> +	LIST_HEAD(head);
>   	u32 seq = n->nlmsg_seq;
>
> -	act = tcf_action_init(net, nla, NULL, NULL, ovr, 0);
> -	if (act == NULL)
> -		goto done;
> -	if (IS_ERR(act)) {
> -		ret = PTR_ERR(act);
> +	ret = tcf_action_init(net, nla, NULL, NULL, ovr, 0, &head);
> +	if (ret)
>   		goto done;
> -	}
>
>   	/* dump then free all the actions after update; inserted policy
>   	 * stays intact
>   	 */
> -	ret = tcf_add_notify(net, act, portid, seq, RTM_NEWACTION, n->nlmsg_flags);
> -	for (a = act; a; a = act) {
> -		act = a->next;
> -		kfree(a);
> -	}
> +	ret = tcf_add_notify(net, &head, portid, seq, RTM_NEWACTION, n->nlmsg_flags);
> +	cleanup_a(&head);
>   done:
>   	return ret;
>   }
> diff --git a/net/sched/cls_api.c b/net/sched/cls_api.c
> index 8e118af..7e5f296 100644
> --- a/net/sched/cls_api.c
> +++ b/net/sched/cls_api.c
> @@ -500,10 +500,8 @@ out:
>   void tcf_exts_destroy(struct tcf_proto *tp, struct tcf_exts *exts)
>   {
>   #ifdef CONFIG_NET_CLS_ACT
> -	if (exts->action) {
> -		tcf_action_destroy(exts->action, TCA_ACT_UNBIND);
> -		exts->action = NULL;
> -	}
> +	tcf_action_destroy(&exts->head, TCA_ACT_UNBIND);
> +	INIT_LIST_HEAD(&exts->head);
>   #endif
>   }
>   EXPORT_SYMBOL(tcf_exts_destroy);
> @@ -518,6 +516,7 @@ int tcf_exts_validate(struct net *net, struct tcf_proto *tp, struct nlattr **tb,
>   	{
>   		struct tc_action *act;
>
> +		INIT_LIST_HEAD(&exts->head);
>   		if (map->police && tb[map->police]) {
>   			act = tcf_action_init_1(net, tb[map->police], rate_tlv,
>   						"police", TCA_ACT_NOREPLACE,
> @@ -525,16 +524,15 @@ int tcf_exts_validate(struct net *net, struct tcf_proto *tp, struct nlattr **tb,
>   			if (IS_ERR(act))
>   				return PTR_ERR(act);
>
> -			act->type = TCA_OLD_COMPAT;
> -			exts->action = act;
> +			act->type = exts->type = TCA_OLD_COMPAT;
> +			list_add(&act->list, &exts->head);
>   		} else if (map->action && tb[map->action]) {
> -			act = tcf_action_init(net, tb[map->action], rate_tlv,
> +			int err;
> +			err = tcf_action_init(net, tb[map->action], rate_tlv,
>   					      NULL, TCA_ACT_NOREPLACE,
> -					      TCA_ACT_BIND);
> -			if (IS_ERR(act))
> -				return PTR_ERR(act);
> -
> -			exts->action = act;
> +					      TCA_ACT_BIND, &exts->head);
> +			if (err)
> +				return err;
>   		}
>   	}
>   #else
> @@ -551,43 +549,45 @@ void tcf_exts_change(struct tcf_proto *tp, struct tcf_exts *dst,
>   		     struct tcf_exts *src)
>   {
>   #ifdef CONFIG_NET_CLS_ACT
> -	if (src->action) {
> -		struct tc_action *act;
> +	if (!list_empty(&src->head)) {
> +		LIST_HEAD(tmp);
>   		tcf_tree_lock(tp);
> -		act = dst->action;
> -		dst->action = src->action;
> +		list_splice_init(&dst->head, &tmp);
> +		list_splice(&src->head, &dst->head);
>   		tcf_tree_unlock(tp);
> -		if (act)
> -			tcf_action_destroy(act, TCA_ACT_UNBIND);
> +		tcf_action_destroy(&tmp, TCA_ACT_UNBIND);
>   	}
>   #endif
>   }
>   EXPORT_SYMBOL(tcf_exts_change);
>
> +#define tcf_exts_first_act(ext) \
> +		list_first_entry(&(exts)->head, struct tc_action, list)
> +
>   int tcf_exts_dump(struct sk_buff *skb, struct tcf_exts *exts,
>   		  const struct tcf_ext_map *map)
>   {
>   #ifdef CONFIG_NET_CLS_ACT
> -	if (map->action && exts->action) {
> +	if (map->action && !list_empty(&exts->head)) {
>   		/*
>   		 * again for backward compatible mode - we want
>   		 * to work with both old and new modes of entering
>   		 * tc data even if iproute2  was newer - jhs
>   		 */
>   		struct nlattr *nest;
> -
> -		if (exts->action->type != TCA_OLD_COMPAT) {
> +		if (exts->type != TCA_OLD_COMPAT) {
>   			nest = nla_nest_start(skb, map->action);
>   			if (nest == NULL)
>   				goto nla_put_failure;
> -			if (tcf_action_dump(skb, exts->action, 0, 0) < 0)
> +			if (tcf_action_dump(skb, &exts->head, 0, 0) < 0)
>   				goto nla_put_failure;
>   			nla_nest_end(skb, nest);
>   		} else if (map->police) {
> +			struct tc_action *act = tcf_exts_first_act(exts);
>   			nest = nla_nest_start(skb, map->police);
>   			if (nest == NULL)
>   				goto nla_put_failure;
> -			if (tcf_action_dump_old(skb, exts->action, 0, 0) < 0)
> +			if (tcf_action_dump_old(skb, act, 0, 0) < 0)
>   				goto nla_put_failure;
>   			nla_nest_end(skb, nest);
>   		}
> @@ -604,13 +604,11 @@ int tcf_exts_dump_stats(struct sk_buff *skb, struct tcf_exts *exts,
>   			const struct tcf_ext_map *map)
>   {
>   #ifdef CONFIG_NET_CLS_ACT
> -	if (exts->action)
> -		if (tcf_action_copy_stats(skb, exts->action, 1) < 0)
> -			goto nla_put_failure;
> +	struct tc_action *a = tcf_exts_first_act(exts);
> +	if (tcf_action_copy_stats(skb, a, 1) < 0)
> +		return -1;
>   #endif
>   	return 0;
> -nla_put_failure: __attribute__ ((unused))
> -	return -1;
>   }
>   EXPORT_SYMBOL(tcf_exts_dump_stats);
>
> diff --git a/net/sched/cls_basic.c b/net/sched/cls_basic.c
> index 636d913..7b9b460 100644
> --- a/net/sched/cls_basic.c
> +++ b/net/sched/cls_basic.c
> @@ -191,6 +191,7 @@ static int basic_change(struct net *net, struct sk_buff *in_skb,
>   	if (f == NULL)
>   		goto errout;
>
> +	tcf_exts_init(&f->exts);
>   	err = -EINVAL;
>   	if (handle)
>   		f->handle = handle;
> diff --git a/net/sched/cls_bpf.c b/net/sched/cls_bpf.c
> index d7c72be..90fe275 100644
> --- a/net/sched/cls_bpf.c
> +++ b/net/sched/cls_bpf.c
> @@ -271,6 +271,7 @@ static int cls_bpf_change(struct net *net, struct sk_buff *in_skb,
>   	if (prog == NULL)
>   		return -ENOBUFS;
>
> +	tcf_exts_init(&prog->exts);
>   	if (handle == 0)
>   		prog->handle = cls_bpf_grab_new_handle(tp, head);
>   	else
> diff --git a/net/sched/cls_cgroup.c b/net/sched/cls_cgroup.c
> index 16006c9..e4fae03 100644
> --- a/net/sched/cls_cgroup.c
> +++ b/net/sched/cls_cgroup.c
> @@ -203,6 +203,7 @@ static int cls_cgroup_change(struct net *net, struct sk_buff *in_skb,
>   		if (head == NULL)
>   			return -ENOBUFS;
>
> +		tcf_exts_init(&head->exts);
>   		head->handle = handle;
>
>   		tcf_tree_lock(tp);
> diff --git a/net/sched/cls_flow.c b/net/sched/cls_flow.c
> index 7881e2f..411e0d8 100644
> --- a/net/sched/cls_flow.c
> +++ b/net/sched/cls_flow.c
> @@ -455,6 +455,7 @@ static int flow_change(struct net *net, struct sk_buff *in_skb,
>
>   		f->handle = handle;
>   		f->mask	  = ~0U;
> +		tcf_exts_init(&f->exts);
>
>   		get_random_bytes(&f->hashrnd, 4);
>   		f->perturb_timer.function = flow_perturbation;
> diff --git a/net/sched/cls_fw.c b/net/sched/cls_fw.c
> index 9b97172..d1cebad 100644
> --- a/net/sched/cls_fw.c
> +++ b/net/sched/cls_fw.c
> @@ -280,6 +280,7 @@ static int fw_change(struct net *net, struct sk_buff *in_skb,
>   	if (f == NULL)
>   		return -ENOBUFS;
>
> +	tcf_exts_init(&f->exts);
>   	f->id = handle;
>
>   	err = fw_change_attrs(net, tp, f, tb, tca, base);
> diff --git a/net/sched/cls_route.c b/net/sched/cls_route.c
> index 37da567..f1f1dfd 100644
> --- a/net/sched/cls_route.c
> +++ b/net/sched/cls_route.c
> @@ -481,6 +481,7 @@ static int route4_change(struct net *net, struct sk_buff *in_skb,
>   	if (f == NULL)
>   		goto errout;
>
> +	tcf_exts_init(&f->exts);
>   	err = route4_set_parms(net, tp, base, f, handle, head, tb,
>   		tca[TCA_RATE], 1);
>   	if (err < 0)
> diff --git a/net/sched/cls_rsvp.h b/net/sched/cls_rsvp.h
> index 252d8b0..b1d3ce5 100644
> --- a/net/sched/cls_rsvp.h
> +++ b/net/sched/cls_rsvp.h
> @@ -471,6 +471,7 @@ static int rsvp_change(struct net *net, struct sk_buff *in_skb,
>   	if (f == NULL)
>   		goto errout2;
>
> +	tcf_exts_init(&f->exts);
>   	h2 = 16;
>   	if (tb[TCA_RSVP_SRC]) {
>   		memcpy(f->src, nla_data(tb[TCA_RSVP_SRC]), sizeof(f->src));
> diff --git a/net/sched/cls_tcindex.c b/net/sched/cls_tcindex.c
> index b86535a..c39bbfc 100644
> --- a/net/sched/cls_tcindex.c
> +++ b/net/sched/cls_tcindex.c
> @@ -215,11 +215,14 @@ tcindex_set_parms(struct net *net, struct tcf_proto *tp, unsigned long base,
>
>   	memcpy(&cp, p, sizeof(cp));
>   	memset(&new_filter_result, 0, sizeof(new_filter_result));
> +	tcf_exts_init(&new_filter_result.exts);
>
>   	if (old_r)
>   		memcpy(&cr, r, sizeof(cr));
> -	else
> +	else {
>   		memset(&cr, 0, sizeof(cr));
> +		tcf_exts_init(&cr.exts);
> +	}
>
>   	if (tb[TCA_TCINDEX_HASH])
>   		cp.hash = nla_get_u32(tb[TCA_TCINDEX_HASH]);
> diff --git a/net/sched/cls_u32.c b/net/sched/cls_u32.c
> index 59e546c..492d9a6 100644
> --- a/net/sched/cls_u32.c
> +++ b/net/sched/cls_u32.c
> @@ -646,6 +646,7 @@ static int u32_change(struct net *net, struct sk_buff *in_skb,
>   	n->ht_up = ht;
>   	n->handle = handle;
>   	n->fshift = s->hmask ? ffs(ntohl(s->hmask)) - 1 : 0;
> +	tcf_exts_init(&n->exts);
>
>   #ifdef CONFIG_CLS_U32_MARK
>   	if (tb[TCA_U32_MARK]) {
>