net/sched/act_bpf.c - kernel/msm-4.9 - Gitiles

 /*
  * Copyright (c) 2015 Jiri Pirko <jiri@resnulli.us>
  *
  * 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.
  */

 #include <linux/module.h>
 #include <linux/init.h>
 #include <linux/kernel.h>
 #include <linux/skbuff.h>
 #include <linux/rtnetlink.h>
 #include <linux/filter.h>
 #include <linux/bpf.h>

 #include <net/netlink.h>
 #include <net/pkt_sched.h>

 #include <linux/tc_act/tc_bpf.h>
 #include <net/tc_act/tc_bpf.h>

 #define BPF_TAB_MASK		15
 #define ACT_BPF_NAME_LEN	256

 struct tcf_bpf_cfg {
 	struct bpf_prog *filter;
 	struct sock_filter *bpf_ops;
 	const char *bpf_name;
 	u32 bpf_fd;
 	u16 bpf_num_ops;
 	bool is_ebpf;
 };

 static int tcf_bpf(struct sk_buff *skb, const struct tc_action *act,
 		   struct tcf_result *res)
 {
 	struct tcf_bpf *prog = act->priv;
 	struct bpf_prog *filter;
 	int action, filter_res;
 	bool at_ingress = G_TC_AT(skb->tc_verd) & AT_INGRESS;

 	if (unlikely(!skb_mac_header_was_set(skb)))
 		return TC_ACT_UNSPEC;

 	tcf_lastuse_update(&prog->tcf_tm);
 	bstats_cpu_update(this_cpu_ptr(prog->common.cpu_bstats), skb);

 	rcu_read_lock();
 	filter = rcu_dereference(prog->filter);
 	if (at_ingress) {
 		__skb_push(skb, skb->mac_len);
 		filter_res = BPF_PROG_RUN(filter, skb);
 		__skb_pull(skb, skb->mac_len);
 	} else {
 		filter_res = BPF_PROG_RUN(filter, skb);
 	}
 	rcu_read_unlock();

 	/* A BPF program may overwrite the default action opcode.
 	 * Similarly as in cls_bpf, if filter_res == -1 we use the
 	 * default action specified from tc.
 	 *
 	 * In case a different well-known TC_ACT opcode has been
 	 * returned, it will overwrite the default one.
 	 *
 	 * For everything else that is unkown, TC_ACT_UNSPEC is
 	 * returned.
 	 */
 	switch (filter_res) {
 	case TC_ACT_PIPE:
 	case TC_ACT_RECLASSIFY:
 	case TC_ACT_OK:
 		action = filter_res;
 		break;
 	case TC_ACT_SHOT:
 		action = filter_res;
 		qstats_drop_inc(this_cpu_ptr(prog->common.cpu_qstats));
 		break;
 	case TC_ACT_UNSPEC:
 		action = prog->tcf_action;
 		break;
 	default:
 		action = TC_ACT_UNSPEC;
 		break;
 	}

 	return action;
 }

 static bool tcf_bpf_is_ebpf(const struct tcf_bpf *prog)
 {
 	return !prog->bpf_ops;
 }

 static int tcf_bpf_dump_bpf_info(const struct tcf_bpf *prog,
 				 struct sk_buff *skb)
 {
 	struct nlattr *nla;

 	if (nla_put_u16(skb, TCA_ACT_BPF_OPS_LEN, prog->bpf_num_ops))
 		return -EMSGSIZE;

 	nla = nla_reserve(skb, TCA_ACT_BPF_OPS, prog->bpf_num_ops *
 			  sizeof(struct sock_filter));
 	if (nla == NULL)
 		return -EMSGSIZE;

 	memcpy(nla_data(nla), prog->bpf_ops, nla_len(nla));

 	return 0;
 }

 static int tcf_bpf_dump_ebpf_info(const struct tcf_bpf *prog,
 				  struct sk_buff *skb)
 {
 	if (nla_put_u32(skb, TCA_ACT_BPF_FD, prog->bpf_fd))
 		return -EMSGSIZE;

 	if (prog->bpf_name &&
 	    nla_put_string(skb, TCA_ACT_BPF_NAME, prog->bpf_name))
 		return -EMSGSIZE;

 	return 0;
 }

 static int tcf_bpf_dump(struct sk_buff *skb, struct tc_action *act,
 			int bind, int ref)
 {
 	unsigned char *tp = skb_tail_pointer(skb);
 	struct tcf_bpf *prog = act->priv;
 	struct tc_act_bpf opt = {
 		.index   = prog->tcf_index,
 		.refcnt  = prog->tcf_refcnt - ref,
 		.bindcnt = prog->tcf_bindcnt - bind,
 		.action  = prog->tcf_action,
 	};
 	struct tcf_t tm;
 	int ret;

 	if (nla_put(skb, TCA_ACT_BPF_PARMS, sizeof(opt), &opt))
 		goto nla_put_failure;

 	if (tcf_bpf_is_ebpf(prog))
 		ret = tcf_bpf_dump_ebpf_info(prog, skb);
 	else
 		ret = tcf_bpf_dump_bpf_info(prog, skb);
 	if (ret)
 		goto nla_put_failure;

 	tm.install = jiffies_to_clock_t(jiffies - prog->tcf_tm.install);
 	tm.lastuse = jiffies_to_clock_t(jiffies - prog->tcf_tm.lastuse);
 	tm.expires = jiffies_to_clock_t(prog->tcf_tm.expires);

 	if (nla_put(skb, TCA_ACT_BPF_TM, sizeof(tm), &tm))
 		goto nla_put_failure;

 	return skb->len;

 nla_put_failure:
 	nlmsg_trim(skb, tp);
 	return -1;
 }

 static const struct nla_policy act_bpf_policy[TCA_ACT_BPF_MAX + 1] = {
 	[TCA_ACT_BPF_PARMS]	= { .len = sizeof(struct tc_act_bpf) },
 	[TCA_ACT_BPF_FD]	= { .type = NLA_U32 },
 	[TCA_ACT_BPF_NAME]	= { .type = NLA_NUL_STRING, .len = ACT_BPF_NAME_LEN },
 	[TCA_ACT_BPF_OPS_LEN]	= { .type = NLA_U16 },
 	[TCA_ACT_BPF_OPS]	= { .type = NLA_BINARY,
 				    .len = sizeof(struct sock_filter) * BPF_MAXINSNS },
 };

 static int tcf_bpf_init_from_ops(struct nlattr **tb, struct tcf_bpf_cfg *cfg)
 {
 	struct sock_filter *bpf_ops;
 	struct sock_fprog_kern fprog_tmp;
 	struct bpf_prog *fp;
 	u16 bpf_size, bpf_num_ops;
 	int ret;

 	bpf_num_ops = nla_get_u16(tb[TCA_ACT_BPF_OPS_LEN]);
 	if (bpf_num_ops	> BPF_MAXINSNS || bpf_num_ops == 0)
 		return -EINVAL;

 	bpf_size = bpf_num_ops * sizeof(*bpf_ops);
 	if (bpf_size != nla_len(tb[TCA_ACT_BPF_OPS]))
 		return -EINVAL;

 	bpf_ops = kzalloc(bpf_size, GFP_KERNEL);
 	if (bpf_ops == NULL)
 		return -ENOMEM;

 	memcpy(bpf_ops, nla_data(tb[TCA_ACT_BPF_OPS]), bpf_size);

 	fprog_tmp.len = bpf_num_ops;
 	fprog_tmp.filter = bpf_ops;

 	ret = bpf_prog_create(&fp, &fprog_tmp);
 	if (ret < 0) {
 		kfree(bpf_ops);
 		return ret;
 	}

 	cfg->bpf_ops = bpf_ops;
 	cfg->bpf_num_ops = bpf_num_ops;
 	cfg->filter = fp;
 	cfg->is_ebpf = false;

 	return 0;
 }

 static int tcf_bpf_init_from_efd(struct nlattr **tb, struct tcf_bpf_cfg *cfg)
 {
 	struct bpf_prog *fp;
 	char *name = NULL;
 	u32 bpf_fd;

 	bpf_fd = nla_get_u32(tb[TCA_ACT_BPF_FD]);

 	fp = bpf_prog_get(bpf_fd);
 	if (IS_ERR(fp))
 		return PTR_ERR(fp);

 	if (fp->type != BPF_PROG_TYPE_SCHED_ACT) {
 		bpf_prog_put(fp);
 		return -EINVAL;
 	}

 	if (tb[TCA_ACT_BPF_NAME]) {
 		name = kmemdup(nla_data(tb[TCA_ACT_BPF_NAME]),
 			       nla_len(tb[TCA_ACT_BPF_NAME]),
 			       GFP_KERNEL);
 		if (!name) {
 			bpf_prog_put(fp);
 			return -ENOMEM;
 		}
 	}

 	cfg->bpf_fd = bpf_fd;
 	cfg->bpf_name = name;
 	cfg->filter = fp;
 	cfg->is_ebpf = true;

 	return 0;
 }

 static void tcf_bpf_cfg_cleanup(const struct tcf_bpf_cfg *cfg)
 {
 	if (cfg->is_ebpf)
 		bpf_prog_put(cfg->filter);
 	else
 		bpf_prog_destroy(cfg->filter);

 	kfree(cfg->bpf_ops);
 	kfree(cfg->bpf_name);
 }

 static void tcf_bpf_prog_fill_cfg(const struct tcf_bpf *prog,
 				  struct tcf_bpf_cfg *cfg)
 {
 	cfg->is_ebpf = tcf_bpf_is_ebpf(prog);
 	/* updates to prog->filter are prevented, since it's called either
 	 * with rtnl lock or during final cleanup in rcu callback
 	 */
 	cfg->filter = rcu_dereference_protected(prog->filter, 1);

 	cfg->bpf_ops = prog->bpf_ops;
 	cfg->bpf_name = prog->bpf_name;
 }

 static int tcf_bpf_init(struct net *net, struct nlattr *nla,
 			struct nlattr *est, struct tc_action *act,
 			int replace, int bind)
 {
 	struct nlattr *tb[TCA_ACT_BPF_MAX + 1];
 	struct tcf_bpf_cfg cfg, old;
 	struct tc_act_bpf *parm;
 	struct tcf_bpf *prog;
 	bool is_bpf, is_ebpf;
 	int ret, res = 0;

 	if (!nla)
 		return -EINVAL;

 	ret = nla_parse_nested(tb, TCA_ACT_BPF_MAX, nla, act_bpf_policy);
 	if (ret < 0)
 		return ret;

 	if (!tb[TCA_ACT_BPF_PARMS])
 		return -EINVAL;

 	parm = nla_data(tb[TCA_ACT_BPF_PARMS]);

 	if (!tcf_hash_check(parm->index, act, bind)) {
 		ret = tcf_hash_create(parm->index, est, act,
 				      sizeof(*prog), bind, true);
 		if (ret < 0)
 			return ret;

 		res = ACT_P_CREATED;
 	} else {
 		/* Don't override defaults. */
 		if (bind)
 			return 0;

 		tcf_hash_release(act, bind);
 		if (!replace)
 			return -EEXIST;
 	}

 	is_bpf = tb[TCA_ACT_BPF_OPS_LEN] && tb[TCA_ACT_BPF_OPS];
 	is_ebpf = tb[TCA_ACT_BPF_FD];

 	if ((!is_bpf && !is_ebpf) || (is_bpf && is_ebpf)) {
 		ret = -EINVAL;
 		goto out;
 	}

 	memset(&cfg, 0, sizeof(cfg));

 	ret = is_bpf ? tcf_bpf_init_from_ops(tb, &cfg) :
 		       tcf_bpf_init_from_efd(tb, &cfg);
 	if (ret < 0)
 		goto out;

 	prog = to_bpf(act);
 	ASSERT_RTNL();

 	if (res != ACT_P_CREATED)
 		tcf_bpf_prog_fill_cfg(prog, &old);

 	prog->bpf_ops = cfg.bpf_ops;
 	prog->bpf_name = cfg.bpf_name;

 	if (cfg.bpf_num_ops)
 		prog->bpf_num_ops = cfg.bpf_num_ops;
 	if (cfg.bpf_fd)
 		prog->bpf_fd = cfg.bpf_fd;

 	prog->tcf_action = parm->action;
 	rcu_assign_pointer(prog->filter, cfg.filter);

 	if (res == ACT_P_CREATED) {
 		tcf_hash_insert(act);
 	} else {
 		/* make sure the program being replaced is no longer executing */
 		synchronize_rcu();
 		tcf_bpf_cfg_cleanup(&old);
 	}

 	return res;
 out:
 	if (res == ACT_P_CREATED)
 		tcf_hash_cleanup(act, est);

 	return ret;
 }

 static void tcf_bpf_cleanup(struct tc_action *act, int bind)
 {
 	struct tcf_bpf_cfg tmp;

 	tcf_bpf_prog_fill_cfg(act->priv, &tmp);
 	tcf_bpf_cfg_cleanup(&tmp);
 }

 static struct tc_action_ops act_bpf_ops __read_mostly = {
 	.kind		=	"bpf",
 	.type		=	TCA_ACT_BPF,
 	.owner		=	THIS_MODULE,
 	.act		=	tcf_bpf,
 	.dump		=	tcf_bpf_dump,
 	.cleanup	=	tcf_bpf_cleanup,
 	.init		=	tcf_bpf_init,
 };

 static int __init bpf_init_module(void)
 {
 	return tcf_register_action(&act_bpf_ops, BPF_TAB_MASK);
 }

 static void __exit bpf_cleanup_module(void)
 {
 	tcf_unregister_action(&act_bpf_ops);
 }

 module_init(bpf_init_module);
 module_exit(bpf_cleanup_module);

 MODULE_AUTHOR("Jiri Pirko <jiri@resnulli.us>");
 MODULE_DESCRIPTION("TC BPF based action");
 MODULE_LICENSE("GPL v2");
	/*
	* Copyright (c) 2015 Jiri Pirko <jiri@resnulli.us>
	*
	* 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.
	*/

	#include <linux/module.h>
	#include <linux/init.h>
	#include <linux/kernel.h>
	#include <linux/skbuff.h>
	#include <linux/rtnetlink.h>
	#include <linux/filter.h>
	#include <linux/bpf.h>

	#include <net/netlink.h>
	#include <net/pkt_sched.h>

	#include <linux/tc_act/tc_bpf.h>
	#include <net/tc_act/tc_bpf.h>

	#define BPF_TAB_MASK 15
	#define ACT_BPF_NAME_LEN 256

	struct tcf_bpf_cfg {
	struct bpf_prog *filter;
	struct sock_filter *bpf_ops;
	const char *bpf_name;
	u32 bpf_fd;
	u16 bpf_num_ops;
	bool is_ebpf;
	};

	static int tcf_bpf(struct sk_buff skb, const struct tc_action act,
	struct tcf_result *res)
	{
	struct tcf_bpf *prog = act->priv;
	struct bpf_prog *filter;
	int action, filter_res;
	bool at_ingress = G_TC_AT(skb->tc_verd) & AT_INGRESS;

	if (unlikely(!skb_mac_header_was_set(skb)))
	return TC_ACT_UNSPEC;

	tcf_lastuse_update(&prog->tcf_tm);
	bstats_cpu_update(this_cpu_ptr(prog->common.cpu_bstats), skb);

	rcu_read_lock();
	filter = rcu_dereference(prog->filter);
	if (at_ingress) {
	__skb_push(skb, skb->mac_len);
	filter_res = BPF_PROG_RUN(filter, skb);
	__skb_pull(skb, skb->mac_len);
	} else {
	filter_res = BPF_PROG_RUN(filter, skb);
	}
	rcu_read_unlock();

	/* A BPF program may overwrite the default action opcode.
	* Similarly as in cls_bpf, if filter_res == -1 we use the
	* default action specified from tc.
	*
	* In case a different well-known TC_ACT opcode has been
	* returned, it will overwrite the default one.
	*
	* For everything else that is unkown, TC_ACT_UNSPEC is
	* returned.
	*/
	switch (filter_res) {
	case TC_ACT_PIPE:
	case TC_ACT_RECLASSIFY:
	case TC_ACT_OK:
	action = filter_res;
	break;
	case TC_ACT_SHOT:
	action = filter_res;
	qstats_drop_inc(this_cpu_ptr(prog->common.cpu_qstats));
	break;
	case TC_ACT_UNSPEC:
	action = prog->tcf_action;
	break;
	default:
	action = TC_ACT_UNSPEC;
	break;
	}

	return action;
	}

	static bool tcf_bpf_is_ebpf(const struct tcf_bpf *prog)
	{
	return !prog->bpf_ops;
	}

	static int tcf_bpf_dump_bpf_info(const struct tcf_bpf *prog,
	struct sk_buff *skb)
	{
	struct nlattr *nla;

	if (nla_put_u16(skb, TCA_ACT_BPF_OPS_LEN, prog->bpf_num_ops))
	return -EMSGSIZE;

	nla = nla_reserve(skb, TCA_ACT_BPF_OPS, prog->bpf_num_ops *
	sizeof(struct sock_filter));
	if (nla == NULL)
	return -EMSGSIZE;

	memcpy(nla_data(nla), prog->bpf_ops, nla_len(nla));

	return 0;
	}

	static int tcf_bpf_dump_ebpf_info(const struct tcf_bpf *prog,
	struct sk_buff *skb)
	{
	if (nla_put_u32(skb, TCA_ACT_BPF_FD, prog->bpf_fd))
	return -EMSGSIZE;

	if (prog->bpf_name &&
	nla_put_string(skb, TCA_ACT_BPF_NAME, prog->bpf_name))
	return -EMSGSIZE;

	return 0;
	}

	static int tcf_bpf_dump(struct sk_buff skb, struct tc_action act,
	int bind, int ref)
	{
	unsigned char *tp = skb_tail_pointer(skb);
	struct tcf_bpf *prog = act->priv;
	struct tc_act_bpf opt = {
	.index = prog->tcf_index,
	.refcnt = prog->tcf_refcnt - ref,
	.bindcnt = prog->tcf_bindcnt - bind,
	.action = prog->tcf_action,
	};
	struct tcf_t tm;
	int ret;

	if (nla_put(skb, TCA_ACT_BPF_PARMS, sizeof(opt), &opt))
	goto nla_put_failure;

	if (tcf_bpf_is_ebpf(prog))
	ret = tcf_bpf_dump_ebpf_info(prog, skb);
	else
	ret = tcf_bpf_dump_bpf_info(prog, skb);
	if (ret)
	goto nla_put_failure;

	tm.install = jiffies_to_clock_t(jiffies - prog->tcf_tm.install);
	tm.lastuse = jiffies_to_clock_t(jiffies - prog->tcf_tm.lastuse);
	tm.expires = jiffies_to_clock_t(prog->tcf_tm.expires);

	if (nla_put(skb, TCA_ACT_BPF_TM, sizeof(tm), &tm))
	goto nla_put_failure;

	return skb->len;

	nla_put_failure:
	nlmsg_trim(skb, tp);
	return -1;
	}

	static const struct nla_policy act_bpf_policy[TCA_ACT_BPF_MAX + 1] = {
	[TCA_ACT_BPF_PARMS] = { .len = sizeof(struct tc_act_bpf) },
	[TCA_ACT_BPF_FD] = { .type = NLA_U32 },
	[TCA_ACT_BPF_NAME] = { .type = NLA_NUL_STRING, .len = ACT_BPF_NAME_LEN },
	[TCA_ACT_BPF_OPS_LEN] = { .type = NLA_U16 },
	[TCA_ACT_BPF_OPS] = { .type = NLA_BINARY,
	.len = sizeof(struct sock_filter) * BPF_MAXINSNS },
	};

	static int tcf_bpf_init_from_ops(struct nlattr *tb, struct tcf_bpf_cfg cfg)
	{
	struct sock_filter *bpf_ops;
	struct sock_fprog_kern fprog_tmp;
	struct bpf_prog *fp;
	u16 bpf_size, bpf_num_ops;
	int ret;

	bpf_num_ops = nla_get_u16(tb[TCA_ACT_BPF_OPS_LEN]);
	if (bpf_num_ops > BPF_MAXINSNS \|\| bpf_num_ops == 0)
	return -EINVAL;

	bpf_size = bpf_num_ops * sizeof(*bpf_ops);
	if (bpf_size != nla_len(tb[TCA_ACT_BPF_OPS]))
	return -EINVAL;

	bpf_ops = kzalloc(bpf_size, GFP_KERNEL);
	if (bpf_ops == NULL)
	return -ENOMEM;

	memcpy(bpf_ops, nla_data(tb[TCA_ACT_BPF_OPS]), bpf_size);

	fprog_tmp.len = bpf_num_ops;
	fprog_tmp.filter = bpf_ops;

	ret = bpf_prog_create(&fp, &fprog_tmp);
	if (ret < 0) {
	kfree(bpf_ops);
	return ret;
	}

	cfg->bpf_ops = bpf_ops;
	cfg->bpf_num_ops = bpf_num_ops;
	cfg->filter = fp;
	cfg->is_ebpf = false;

	return 0;
	}

	static int tcf_bpf_init_from_efd(struct nlattr *tb, struct tcf_bpf_cfg cfg)
	{
	struct bpf_prog *fp;
	char *name = NULL;
	u32 bpf_fd;

	bpf_fd = nla_get_u32(tb[TCA_ACT_BPF_FD]);

	fp = bpf_prog_get(bpf_fd);
	if (IS_ERR(fp))
	return PTR_ERR(fp);

	if (fp->type != BPF_PROG_TYPE_SCHED_ACT) {
	bpf_prog_put(fp);
	return -EINVAL;
	}

	if (tb[TCA_ACT_BPF_NAME]) {
	name = kmemdup(nla_data(tb[TCA_ACT_BPF_NAME]),
	nla_len(tb[TCA_ACT_BPF_NAME]),
	GFP_KERNEL);
	if (!name) {
	bpf_prog_put(fp);
	return -ENOMEM;
	}
	}

	cfg->bpf_fd = bpf_fd;
	cfg->bpf_name = name;
	cfg->filter = fp;
	cfg->is_ebpf = true;

	return 0;
	}

	static void tcf_bpf_cfg_cleanup(const struct tcf_bpf_cfg *cfg)
	{
	if (cfg->is_ebpf)
	bpf_prog_put(cfg->filter);
	else
	bpf_prog_destroy(cfg->filter);

	kfree(cfg->bpf_ops);
	kfree(cfg->bpf_name);
	}

	static void tcf_bpf_prog_fill_cfg(const struct tcf_bpf *prog,
	struct tcf_bpf_cfg *cfg)
	{
	cfg->is_ebpf = tcf_bpf_is_ebpf(prog);
	/* updates to prog->filter are prevented, since it's called either
	* with rtnl lock or during final cleanup in rcu callback
	*/
	cfg->filter = rcu_dereference_protected(prog->filter, 1);

	cfg->bpf_ops = prog->bpf_ops;
	cfg->bpf_name = prog->bpf_name;
	}

	static int tcf_bpf_init(struct net net, struct nlattr nla,
	struct nlattr est, struct tc_action act,
	int replace, int bind)
	{
	struct nlattr *tb[TCA_ACT_BPF_MAX + 1];
	struct tcf_bpf_cfg cfg, old;
	struct tc_act_bpf *parm;
	struct tcf_bpf *prog;
	bool is_bpf, is_ebpf;
	int ret, res = 0;

	if (!nla)
	return -EINVAL;

	ret = nla_parse_nested(tb, TCA_ACT_BPF_MAX, nla, act_bpf_policy);
	if (ret < 0)
	return ret;

	if (!tb[TCA_ACT_BPF_PARMS])
	return -EINVAL;

	parm = nla_data(tb[TCA_ACT_BPF_PARMS]);

	if (!tcf_hash_check(parm->index, act, bind)) {
	ret = tcf_hash_create(parm->index, est, act,
	sizeof(*prog), bind, true);
	if (ret < 0)
	return ret;

	res = ACT_P_CREATED;
	} else {
	/* Don't override defaults. */
	if (bind)
	return 0;

	tcf_hash_release(act, bind);
	if (!replace)
	return -EEXIST;
	}

	is_bpf = tb[TCA_ACT_BPF_OPS_LEN] && tb[TCA_ACT_BPF_OPS];
	is_ebpf = tb[TCA_ACT_BPF_FD];

	if ((!is_bpf && !is_ebpf) \|\| (is_bpf && is_ebpf)) {
	ret = -EINVAL;
	goto out;
	}

	memset(&cfg, 0, sizeof(cfg));

	ret = is_bpf ? tcf_bpf_init_from_ops(tb, &cfg) :
	tcf_bpf_init_from_efd(tb, &cfg);
	if (ret < 0)
	goto out;

	prog = to_bpf(act);
	ASSERT_RTNL();

	if (res != ACT_P_CREATED)
	tcf_bpf_prog_fill_cfg(prog, &old);

	prog->bpf_ops = cfg.bpf_ops;
	prog->bpf_name = cfg.bpf_name;

	if (cfg.bpf_num_ops)
	prog->bpf_num_ops = cfg.bpf_num_ops;
	if (cfg.bpf_fd)
	prog->bpf_fd = cfg.bpf_fd;

	prog->tcf_action = parm->action;
	rcu_assign_pointer(prog->filter, cfg.filter);

	if (res == ACT_P_CREATED) {
	tcf_hash_insert(act);
	} else {
	/* make sure the program being replaced is no longer executing */
	synchronize_rcu();
	tcf_bpf_cfg_cleanup(&old);
	}

	return res;
	out:
	if (res == ACT_P_CREATED)
	tcf_hash_cleanup(act, est);

	return ret;
	}

	static void tcf_bpf_cleanup(struct tc_action *act, int bind)
	{
	struct tcf_bpf_cfg tmp;

	tcf_bpf_prog_fill_cfg(act->priv, &tmp);
	tcf_bpf_cfg_cleanup(&tmp);
	}

	static struct tc_action_ops act_bpf_ops __read_mostly = {
	.kind = "bpf",
	.type = TCA_ACT_BPF,
	.owner = THIS_MODULE,
	.act = tcf_bpf,
	.dump = tcf_bpf_dump,
	.cleanup = tcf_bpf_cleanup,
	.init = tcf_bpf_init,
	};

	static int __init bpf_init_module(void)
	{
	return tcf_register_action(&act_bpf_ops, BPF_TAB_MASK);
	}

	static void __exit bpf_cleanup_module(void)
	{
	tcf_unregister_action(&act_bpf_ops);
	}

	module_init(bpf_init_module);
	module_exit(bpf_cleanup_module);

	MODULE_AUTHOR("Jiri Pirko <jiri@resnulli.us>");
	MODULE_DESCRIPTION("TC BPF based action");
	MODULE_LICENSE("GPL v2");