linux/net/sched/cls_matchall.c
Yotam Gigi ec2507d2a3 net/sched: cls_matchall: Fix error path
Fix several error paths in matchall:
 - Release reference to actions in case the hardware fails offloading
   (relevant to skip_sw only)
 - Fix error path in case tcf_exts initialization/validation fail

Fixes: bf3994d2ed ("net/sched: introduce Match-all classifier")
Signed-off-by: Yotam Gigi <yotamg@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-01-03 18:58:27 -05:00

328 lines
7.4 KiB
C

/*
* net/sched/cls_matchll.c Match-all classifier
*
* Copyright (c) 2016 Jiri Pirko <jiri@mellanox.com>
*
* 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/kernel.h>
#include <linux/init.h>
#include <linux/module.h>
#include <net/sch_generic.h>
#include <net/pkt_cls.h>
struct cls_mall_filter {
struct tcf_exts exts;
struct tcf_result res;
u32 handle;
struct rcu_head rcu;
u32 flags;
};
struct cls_mall_head {
struct cls_mall_filter *filter;
struct rcu_head rcu;
};
static int mall_classify(struct sk_buff *skb, const struct tcf_proto *tp,
struct tcf_result *res)
{
struct cls_mall_head *head = rcu_dereference_bh(tp->root);
struct cls_mall_filter *f = head->filter;
if (tc_skip_sw(f->flags))
return -1;
return tcf_exts_exec(skb, &f->exts, res);
}
static int mall_init(struct tcf_proto *tp)
{
struct cls_mall_head *head;
head = kzalloc(sizeof(*head), GFP_KERNEL);
if (!head)
return -ENOBUFS;
rcu_assign_pointer(tp->root, head);
return 0;
}
static void mall_destroy_filter(struct rcu_head *head)
{
struct cls_mall_filter *f = container_of(head, struct cls_mall_filter, rcu);
tcf_exts_destroy(&f->exts);
kfree(f);
}
static int mall_replace_hw_filter(struct tcf_proto *tp,
struct cls_mall_filter *f,
unsigned long cookie)
{
struct net_device *dev = tp->q->dev_queue->dev;
struct tc_to_netdev offload;
struct tc_cls_matchall_offload mall_offload = {0};
offload.type = TC_SETUP_MATCHALL;
offload.cls_mall = &mall_offload;
offload.cls_mall->command = TC_CLSMATCHALL_REPLACE;
offload.cls_mall->exts = &f->exts;
offload.cls_mall->cookie = cookie;
return dev->netdev_ops->ndo_setup_tc(dev, tp->q->handle, tp->protocol,
&offload);
}
static void mall_destroy_hw_filter(struct tcf_proto *tp,
struct cls_mall_filter *f,
unsigned long cookie)
{
struct net_device *dev = tp->q->dev_queue->dev;
struct tc_to_netdev offload;
struct tc_cls_matchall_offload mall_offload = {0};
offload.type = TC_SETUP_MATCHALL;
offload.cls_mall = &mall_offload;
offload.cls_mall->command = TC_CLSMATCHALL_DESTROY;
offload.cls_mall->exts = NULL;
offload.cls_mall->cookie = cookie;
dev->netdev_ops->ndo_setup_tc(dev, tp->q->handle, tp->protocol,
&offload);
}
static bool mall_destroy(struct tcf_proto *tp, bool force)
{
struct cls_mall_head *head = rtnl_dereference(tp->root);
struct net_device *dev = tp->q->dev_queue->dev;
struct cls_mall_filter *f = head->filter;
if (!force && f)
return false;
if (f) {
if (tc_should_offload(dev, tp, f->flags))
mall_destroy_hw_filter(tp, f, (unsigned long) f);
call_rcu(&f->rcu, mall_destroy_filter);
}
kfree_rcu(head, rcu);
return true;
}
static unsigned long mall_get(struct tcf_proto *tp, u32 handle)
{
struct cls_mall_head *head = rtnl_dereference(tp->root);
struct cls_mall_filter *f = head->filter;
if (f && f->handle == handle)
return (unsigned long) f;
return 0;
}
static const struct nla_policy mall_policy[TCA_MATCHALL_MAX + 1] = {
[TCA_MATCHALL_UNSPEC] = { .type = NLA_UNSPEC },
[TCA_MATCHALL_CLASSID] = { .type = NLA_U32 },
};
static int mall_set_parms(struct net *net, struct tcf_proto *tp,
struct cls_mall_filter *f,
unsigned long base, struct nlattr **tb,
struct nlattr *est, bool ovr)
{
struct tcf_exts e;
int err;
err = tcf_exts_init(&e, TCA_MATCHALL_ACT, 0);
if (err)
return err;
err = tcf_exts_validate(net, tp, tb, est, &e, ovr);
if (err < 0)
goto errout;
if (tb[TCA_MATCHALL_CLASSID]) {
f->res.classid = nla_get_u32(tb[TCA_MATCHALL_CLASSID]);
tcf_bind_filter(tp, &f->res, base);
}
tcf_exts_change(tp, &f->exts, &e);
return 0;
errout:
tcf_exts_destroy(&e);
return err;
}
static int mall_change(struct net *net, struct sk_buff *in_skb,
struct tcf_proto *tp, unsigned long base,
u32 handle, struct nlattr **tca,
unsigned long *arg, bool ovr)
{
struct cls_mall_head *head = rtnl_dereference(tp->root);
struct cls_mall_filter *fold = (struct cls_mall_filter *) *arg;
struct net_device *dev = tp->q->dev_queue->dev;
struct cls_mall_filter *f;
struct nlattr *tb[TCA_MATCHALL_MAX + 1];
u32 flags = 0;
int err;
if (!tca[TCA_OPTIONS])
return -EINVAL;
if (head->filter)
return -EBUSY;
if (fold)
return -EINVAL;
err = nla_parse_nested(tb, TCA_MATCHALL_MAX,
tca[TCA_OPTIONS], mall_policy);
if (err < 0)
return err;
if (tb[TCA_MATCHALL_FLAGS]) {
flags = nla_get_u32(tb[TCA_MATCHALL_FLAGS]);
if (!tc_flags_valid(flags))
return -EINVAL;
}
f = kzalloc(sizeof(*f), GFP_KERNEL);
if (!f)
return -ENOBUFS;
err = tcf_exts_init(&f->exts, TCA_MATCHALL_ACT, 0);
if (err)
goto err_exts_init;
if (!handle)
handle = 1;
f->handle = handle;
f->flags = flags;
err = mall_set_parms(net, tp, f, base, tb, tca[TCA_RATE], ovr);
if (err)
goto err_set_parms;
if (tc_should_offload(dev, tp, flags)) {
err = mall_replace_hw_filter(tp, f, (unsigned long) f);
if (err) {
if (tc_skip_sw(flags))
goto err_replace_hw_filter;
else
err = 0;
}
}
*arg = (unsigned long) f;
rcu_assign_pointer(head->filter, f);
return 0;
err_replace_hw_filter:
err_set_parms:
tcf_exts_destroy(&f->exts);
err_exts_init:
kfree(f);
return err;
}
static int mall_delete(struct tcf_proto *tp, unsigned long arg)
{
struct cls_mall_head *head = rtnl_dereference(tp->root);
struct cls_mall_filter *f = (struct cls_mall_filter *) arg;
struct net_device *dev = tp->q->dev_queue->dev;
if (tc_should_offload(dev, tp, f->flags))
mall_destroy_hw_filter(tp, f, (unsigned long) f);
RCU_INIT_POINTER(head->filter, NULL);
tcf_unbind_filter(tp, &f->res);
call_rcu(&f->rcu, mall_destroy_filter);
return 0;
}
static void mall_walk(struct tcf_proto *tp, struct tcf_walker *arg)
{
struct cls_mall_head *head = rtnl_dereference(tp->root);
struct cls_mall_filter *f = head->filter;
if (arg->count < arg->skip)
goto skip;
if (arg->fn(tp, (unsigned long) f, arg) < 0)
arg->stop = 1;
skip:
arg->count++;
}
static int mall_dump(struct net *net, struct tcf_proto *tp, unsigned long fh,
struct sk_buff *skb, struct tcmsg *t)
{
struct cls_mall_filter *f = (struct cls_mall_filter *) fh;
struct nlattr *nest;
if (!f)
return skb->len;
t->tcm_handle = f->handle;
nest = nla_nest_start(skb, TCA_OPTIONS);
if (!nest)
goto nla_put_failure;
if (f->res.classid &&
nla_put_u32(skb, TCA_MATCHALL_CLASSID, f->res.classid))
goto nla_put_failure;
if (tcf_exts_dump(skb, &f->exts))
goto nla_put_failure;
nla_nest_end(skb, nest);
if (tcf_exts_dump_stats(skb, &f->exts) < 0)
goto nla_put_failure;
return skb->len;
nla_put_failure:
nla_nest_cancel(skb, nest);
return -1;
}
static struct tcf_proto_ops cls_mall_ops __read_mostly = {
.kind = "matchall",
.classify = mall_classify,
.init = mall_init,
.destroy = mall_destroy,
.get = mall_get,
.change = mall_change,
.delete = mall_delete,
.walk = mall_walk,
.dump = mall_dump,
.owner = THIS_MODULE,
};
static int __init cls_mall_init(void)
{
return register_tcf_proto_ops(&cls_mall_ops);
}
static void __exit cls_mall_exit(void)
{
unregister_tcf_proto_ops(&cls_mall_ops);
}
module_init(cls_mall_init);
module_exit(cls_mall_exit);
MODULE_AUTHOR("Jiri Pirko <jiri@mellanox.com>");
MODULE_DESCRIPTION("Match-all classifier");
MODULE_LICENSE("GPL v2");