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Diffstat (limited to 'net/sched/act_mirred.c')
-rw-r--r--net/sched/act_mirred.c95
1 files changed, 72 insertions, 23 deletions
diff --git a/net/sched/act_mirred.c b/net/sched/act_mirred.c
index fd34015331ab..b26d060da08e 100644
--- a/net/sched/act_mirred.c
+++ b/net/sched/act_mirred.c
@@ -25,6 +25,7 @@
#include <net/net_namespace.h>
#include <net/netlink.h>
#include <net/pkt_sched.h>
+#include <net/pkt_cls.h>
#include <linux/tc_act/tc_mirred.h>
#include <net/tc_act/tc_mirred.h>
@@ -49,6 +50,18 @@ static bool tcf_mirred_act_wants_ingress(int action)
}
}
+static bool tcf_mirred_can_reinsert(int action)
+{
+ switch (action) {
+ case TC_ACT_SHOT:
+ case TC_ACT_STOLEN:
+ case TC_ACT_QUEUED:
+ case TC_ACT_TRAP:
+ return true;
+ }
+ return false;
+}
+
static void tcf_mirred_release(struct tc_action *a)
{
struct tcf_mirred *m = to_mirred(a);
@@ -68,8 +81,9 @@ static unsigned int mirred_net_id;
static struct tc_action_ops act_mirred_ops;
static int tcf_mirred_init(struct net *net, struct nlattr *nla,
- struct nlattr *est, struct tc_action **a, int ovr,
- int bind, struct netlink_ext_ack *extack)
+ struct nlattr *est, struct tc_action **a,
+ int ovr, int bind, bool rtnl_held,
+ struct netlink_ext_ack *extack)
{
struct tc_action_net *tn = net_generic(net, mirred_net_id);
struct nlattr *tb[TCA_MIRRED_MAX + 1];
@@ -78,7 +92,7 @@ static int tcf_mirred_init(struct net *net, struct nlattr *nla,
struct tcf_mirred *m;
struct net_device *dev;
bool exists = false;
- int ret;
+ int ret, err;
if (!nla) {
NL_SET_ERR_MSG_MOD(extack, "Mirred requires attributes to be passed");
@@ -93,7 +107,10 @@ static int tcf_mirred_init(struct net *net, struct nlattr *nla,
}
parm = nla_data(tb[TCA_MIRRED_PARMS]);
- exists = tcf_idr_check(tn, parm->index, a, bind);
+ err = tcf_idr_check_alloc(tn, &parm->index, a, bind);
+ if (err < 0)
+ return err;
+ exists = err;
if (exists && bind)
return 0;
@@ -106,6 +123,8 @@ static int tcf_mirred_init(struct net *net, struct nlattr *nla,
default:
if (exists)
tcf_idr_release(*a, bind);
+ else
+ tcf_idr_cleanup(tn, parm->index);
NL_SET_ERR_MSG_MOD(extack, "Unknown mirred option");
return -EINVAL;
}
@@ -114,6 +133,8 @@ static int tcf_mirred_init(struct net *net, struct nlattr *nla,
if (dev == NULL) {
if (exists)
tcf_idr_release(*a, bind);
+ else
+ tcf_idr_cleanup(tn, parm->index);
return -ENODEV;
}
mac_header_xmit = dev_is_mac_header_xmit(dev);
@@ -123,18 +144,20 @@ static int tcf_mirred_init(struct net *net, struct nlattr *nla,
if (!exists) {
if (!dev) {
+ tcf_idr_cleanup(tn, parm->index);
NL_SET_ERR_MSG_MOD(extack, "Specified device does not exist");
return -EINVAL;
}
ret = tcf_idr_create(tn, parm->index, est, a,
&act_mirred_ops, bind, true);
- if (ret)
+ if (ret) {
+ tcf_idr_cleanup(tn, parm->index);
return ret;
+ }
ret = ACT_P_CREATED;
- } else {
+ } else if (!ovr) {
tcf_idr_release(*a, bind);
- if (!ovr)
- return -EEXIST;
+ return -EEXIST;
}
m = to_mirred(*a);
@@ -161,21 +184,23 @@ static int tcf_mirred(struct sk_buff *skb, const struct tc_action *a,
struct tcf_result *res)
{
struct tcf_mirred *m = to_mirred(a);
+ struct sk_buff *skb2 = skb;
bool m_mac_header_xmit;
struct net_device *dev;
- struct sk_buff *skb2;
int retval, err = 0;
+ bool use_reinsert;
+ bool want_ingress;
+ bool is_redirect;
int m_eaction;
int mac_len;
tcf_lastuse_update(&m->tcf_tm);
bstats_cpu_update(this_cpu_ptr(m->common.cpu_bstats), skb);
- rcu_read_lock();
m_mac_header_xmit = READ_ONCE(m->tcfm_mac_header_xmit);
m_eaction = READ_ONCE(m->tcfm_eaction);
retval = READ_ONCE(m->tcf_action);
- dev = rcu_dereference(m->tcfm_dev);
+ dev = rcu_dereference_bh(m->tcfm_dev);
if (unlikely(!dev)) {
pr_notice_once("tc mirred: target device is gone\n");
goto out;
@@ -187,16 +212,25 @@ static int tcf_mirred(struct sk_buff *skb, const struct tc_action *a,
goto out;
}
- skb2 = skb_clone(skb, GFP_ATOMIC);
- if (!skb2)
- goto out;
+ /* we could easily avoid the clone only if called by ingress and clsact;
+ * since we can't easily detect the clsact caller, skip clone only for
+ * ingress - that covers the TC S/W datapath.
+ */
+ is_redirect = tcf_mirred_is_act_redirect(m_eaction);
+ use_reinsert = skb_at_tc_ingress(skb) && is_redirect &&
+ tcf_mirred_can_reinsert(retval);
+ if (!use_reinsert) {
+ skb2 = skb_clone(skb, GFP_ATOMIC);
+ if (!skb2)
+ goto out;
+ }
/* If action's target direction differs than filter's direction,
* and devices expect a mac header on xmit, then mac push/pull is
* needed.
*/
- if (skb_at_tc_ingress(skb) != tcf_mirred_act_wants_ingress(m_eaction) &&
- m_mac_header_xmit) {
+ want_ingress = tcf_mirred_act_wants_ingress(m_eaction);
+ if (skb_at_tc_ingress(skb) != want_ingress && m_mac_header_xmit) {
if (!skb_at_tc_ingress(skb)) {
/* caught at egress, act ingress: pull mac */
mac_len = skb_network_header(skb) - skb_mac_header(skb);
@@ -207,15 +241,23 @@ static int tcf_mirred(struct sk_buff *skb, const struct tc_action *a,
}
}
+ skb2->skb_iif = skb->dev->ifindex;
+ skb2->dev = dev;
+
/* mirror is always swallowed */
- if (tcf_mirred_is_act_redirect(m_eaction)) {
+ if (is_redirect) {
skb2->tc_redirected = 1;
skb2->tc_from_ingress = skb2->tc_at_ingress;
+
+ /* let's the caller reinsert the packet, if possible */
+ if (use_reinsert) {
+ res->ingress = want_ingress;
+ res->qstats = this_cpu_ptr(m->common.cpu_qstats);
+ return TC_ACT_REINSERT;
+ }
}
- skb2->skb_iif = skb->dev->ifindex;
- skb2->dev = dev;
- if (!tcf_mirred_act_wants_ingress(m_eaction))
+ if (!want_ingress)
err = dev_queue_xmit(skb2);
else
err = netif_receive_skb(skb2);
@@ -226,7 +268,6 @@ out:
if (tcf_mirred_is_act_redirect(m_eaction))
retval = TC_ACT_SHOT;
}
- rcu_read_unlock();
return retval;
}
@@ -250,8 +291,8 @@ static int tcf_mirred_dump(struct sk_buff *skb, struct tc_action *a, int bind,
struct tc_mirred opt = {
.index = m->tcf_index,
.action = m->tcf_action,
- .refcnt = m->tcf_refcnt - ref,
- .bindcnt = m->tcf_bindcnt - bind,
+ .refcnt = refcount_read(&m->tcf_refcnt) - ref,
+ .bindcnt = atomic_read(&m->tcf_bindcnt) - bind,
.eaction = m->tcfm_eaction,
.ifindex = dev ? dev->ifindex : 0,
};
@@ -321,6 +362,13 @@ static struct net_device *tcf_mirred_get_dev(const struct tc_action *a)
return rtnl_dereference(m->tcfm_dev);
}
+static int tcf_mirred_delete(struct net *net, u32 index)
+{
+ struct tc_action_net *tn = net_generic(net, mirred_net_id);
+
+ return tcf_idr_delete_index(tn, index);
+}
+
static struct tc_action_ops act_mirred_ops = {
.kind = "mirred",
.type = TCA_ACT_MIRRED,
@@ -334,6 +382,7 @@ static struct tc_action_ops act_mirred_ops = {
.lookup = tcf_mirred_search,
.size = sizeof(struct tcf_mirred),
.get_dev = tcf_mirred_get_dev,
+ .delete = tcf_mirred_delete,
};
static __net_init int mirred_init_net(struct net *net)
generated by cgit v1.2.3 (git 2.39.0) at 2025-09-03 08:38:06 +0300