net/hsr: Move slave init to hsr_slave.c.

Also try to prevent some possible slave dereference race conditions. This is
finalized in the next patch, which abandons the slave array in favour of
a list_head list and list RCU.

Signed-off-by: Arvid Brodin <arvid.brodin@alten.se>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Arvid Brodin 2014-07-04 23:37:27 +02:00 committed by David S. Miller
parent e9aae56ea4
commit 51f3c60531
6 changed files with 203 additions and 162 deletions

View file

@ -15,7 +15,6 @@
#include <linux/netdevice.h>
#include <linux/skbuff.h>
#include <linux/etherdevice.h>
#include <linux/if_arp.h>
#include <linux/rtnetlink.h>
#include <linux/pkt_sched.h>
#include "hsr_device.h"
@ -108,23 +107,27 @@ void hsr_check_carrier_and_operstate(struct hsr_priv *hsr)
hsr_check_announce(hsr->dev, old_operstate);
}
int hsr_get_max_mtu(struct hsr_priv *hsr)
{
int mtu_max;
unsigned int mtu_max;
struct net_device *slave;
if (hsr->slave[0] && hsr->slave[1])
mtu_max = min(hsr->slave[0]->mtu, hsr->slave[1]->mtu);
else if (hsr->slave[0])
mtu_max = hsr->slave[0]->mtu;
else if (hsr->slave[1])
mtu_max = hsr->slave[1]->mtu;
else
mtu_max = HSR_HLEN;
mtu_max = ETH_DATA_LEN;
rcu_read_lock();
slave = hsr->slave[0];
if (slave)
mtu_max = min(slave->mtu, mtu_max);
slave = hsr->slave[1];
if (slave)
mtu_max = min(slave->mtu, mtu_max);
rcu_read_unlock();
if (mtu_max < HSR_HLEN)
return 0;
return mtu_max - HSR_HLEN;
}
static int hsr_dev_change_mtu(struct net_device *dev, int new_mtu)
{
struct hsr_priv *hsr;
@ -145,18 +148,20 @@ static int hsr_dev_change_mtu(struct net_device *dev, int new_mtu)
static int hsr_dev_open(struct net_device *dev)
{
struct hsr_priv *hsr;
struct net_device *slave;
int i;
char *slave_name;
hsr = netdev_priv(dev);
for (i = 0; i < HSR_MAX_SLAVE; i++) {
if (hsr->slave[i])
slave_name = hsr->slave[i]->name;
slave = hsr->slave[i];
if (slave)
slave_name = slave->name;
else
slave_name = "null";
if (!is_slave_up(hsr->slave[i]))
if (!is_slave_up(slave))
netdev_warn(dev, "Slave %c (%s) is not up; please bring it up to get a working HSR network\n",
'A' + i, slave_name);
}
@ -223,6 +228,8 @@ static int slave_xmit(struct sk_buff *skb, struct hsr_priv *hsr,
hsr_ethhdr = (struct hsr_ethhdr *) skb->data;
skb->dev = hsr->slave[dev_idx];
if (unlikely(!skb->dev))
return NET_XMIT_DROP;
hsr_addr_subst_dest(hsr, &hsr_ethhdr->ethhdr, dev_idx);
@ -252,14 +259,8 @@ static int hsr_dev_xmit(struct sk_buff *skb, struct net_device *dev)
}
skb2 = pskb_copy(skb, GFP_ATOMIC);
res1 = NET_XMIT_DROP;
if (likely(hsr->slave[HSR_DEV_SLAVE_A]))
res1 = slave_xmit(skb, hsr, HSR_DEV_SLAVE_A);
res2 = NET_XMIT_DROP;
if (likely(skb2 && hsr->slave[HSR_DEV_SLAVE_B]))
res2 = slave_xmit(skb2, hsr, HSR_DEV_SLAVE_B);
res1 = slave_xmit(skb, hsr, HSR_DEV_SLAVE_A);
res2 = slave_xmit(skb2, hsr, HSR_DEV_SLAVE_B);
if (likely(res1 == NET_XMIT_SUCCESS || res1 == NET_XMIT_CN ||
res2 == NET_XMIT_SUCCESS || res2 == NET_XMIT_CN)) {
@ -406,28 +407,10 @@ static void hsr_announce(unsigned long data)
static void restore_slaves(struct net_device *hsr_dev)
{
struct hsr_priv *hsr;
int i;
int res;
hsr = netdev_priv(hsr_dev);
rtnl_lock();
for (i = 0; i < HSR_MAX_SLAVE; i++) {
if (!hsr->slave[i])
continue;
res = dev_set_promiscuity(hsr->slave[i], -1);
if (res)
netdev_info(hsr_dev,
"Cannot restore slave promiscuity (%s, %d)\n",
hsr->slave[i]->name, res);
if (hsr->slave[i]->rx_handler == hsr_handle_frame)
netdev_rx_handler_unregister(hsr->slave[i]);
}
rtnl_unlock();
hsr_del_slave(hsr, 1);
hsr_del_slave(hsr, 0);
}
static void reclaim_hsr_dev(struct rcu_head *rh)
@ -483,38 +466,6 @@ bool is_hsr_master(struct net_device *dev)
return (dev->netdev_ops->ndo_start_xmit == hsr_dev_xmit);
}
static int check_slave_ok(struct net_device *dev)
{
/* Don't allow HSR on non-ethernet like devices */
if ((dev->flags & IFF_LOOPBACK) || (dev->type != ARPHRD_ETHER) ||
(dev->addr_len != ETH_ALEN)) {
netdev_info(dev, "Cannot use loopback or non-ethernet device as HSR slave.\n");
return -EINVAL;
}
/* Don't allow enslaving hsr devices */
if (is_hsr_master(dev)) {
netdev_info(dev, "Cannot create trees of HSR devices.\n");
return -EINVAL;
}
if (is_hsr_slave(dev)) {
netdev_info(dev, "This device is already a HSR slave.\n");
return -EINVAL;
}
if (dev->priv_flags & IFF_802_1Q_VLAN) {
netdev_info(dev, "HSR on top of VLAN is not yet supported in this driver.\n");
return -EINVAL;
}
/* HSR over bonded devices has not been tested, but I'm not sure it
* won't work...
*/
return 0;
}
/* Default multicast address for HSR Supervision frames */
static const unsigned char def_multicast_addr[ETH_ALEN] __aligned(2) = {
@ -525,15 +476,30 @@ int hsr_dev_finalize(struct net_device *hsr_dev, struct net_device *slave[2],
unsigned char multicast_spec)
{
struct hsr_priv *hsr;
int i;
int res;
hsr = netdev_priv(hsr_dev);
hsr->dev = hsr_dev;
hsr->slave[0] = NULL;
hsr->slave[1] = NULL;
INIT_LIST_HEAD(&hsr->node_db);
INIT_LIST_HEAD(&hsr->self_node_db);
for (i = 0; i < HSR_MAX_SLAVE; i++)
hsr->slave[i] = slave[i];
ether_addr_copy(hsr_dev->dev_addr, slave[0]->dev_addr);
/* Make sure we recognize frames from ourselves in hsr_rcv() */
res = hsr_create_self_node(&hsr->self_node_db, hsr_dev->dev_addr,
slave[1]->dev_addr);
if (res < 0)
return res;
hsr_dev->features = slave[0]->features & slave[1]->features;
/* Prevent recursive tx locking */
hsr_dev->features |= NETIF_F_LLTX;
/* VLAN on top of HSR needs testing and probably some work on
* hsr_header_create() etc.
*/
hsr_dev->features |= NETIF_F_VLAN_CHALLENGED;
spin_lock_init(&hsr->seqnr_lock);
/* Overflow soon to find bugs easier: */
@ -560,65 +526,21 @@ int hsr_dev_finalize(struct net_device *hsr_dev, struct net_device *slave[2],
* IFF_HSR_MASTER/SLAVE?
*/
for (i = 0; i < HSR_MAX_SLAVE; i++) {
res = check_slave_ok(slave[i]);
if (res)
return res;
}
hsr_dev->features = slave[0]->features & slave[1]->features;
/* Prevent recursive tx locking */
hsr_dev->features |= NETIF_F_LLTX;
/* VLAN on top of HSR needs testing and probably some work on
* hsr_header_create() etc.
*/
hsr_dev->features |= NETIF_F_VLAN_CHALLENGED;
/* Set hsr_dev's MAC address to that of mac_slave1 */
ether_addr_copy(hsr_dev->dev_addr, hsr->slave[0]->dev_addr);
/* Set required header length */
for (i = 0; i < HSR_MAX_SLAVE; i++) {
if (slave[i]->hard_header_len + HSR_HLEN >
hsr_dev->hard_header_len)
hsr_dev->hard_header_len =
slave[i]->hard_header_len + HSR_HLEN;
}
/* MTU */
for (i = 0; i < HSR_MAX_SLAVE; i++)
if (slave[i]->mtu - HSR_HLEN < hsr_dev->mtu)
hsr_dev->mtu = slave[i]->mtu - HSR_HLEN;
/* Make sure the 1st call to netif_carrier_on() gets through */
netif_carrier_off(hsr_dev);
/* Promiscuity */
for (i = 0; i < HSR_MAX_SLAVE; i++) {
res = dev_set_promiscuity(slave[i], 1);
if (res) {
netdev_info(hsr_dev, "Cannot set slave promiscuity (%s, %d)\n",
slave[i]->name, res);
goto fail;
}
}
for (i = 0; i < HSR_MAX_SLAVE; i++) {
res = netdev_rx_handler_register(slave[i], hsr_handle_frame,
hsr);
if (res)
goto fail;
}
/* Make sure we recognize frames from ourselves in hsr_rcv() */
res = hsr_create_self_node(&hsr->self_node_db, hsr_dev->dev_addr,
hsr->slave[1]->dev_addr);
if (res < 0)
goto fail;
res = register_netdevice(hsr_dev);
if (res)
goto fail;
return res;
res = hsr_add_slave(hsr, slave[0], 0);
if (res)
return res;
res = hsr_add_slave(hsr, slave[1], 1);
if (res) {
hsr_del_slave(hsr, 0);
return res;
}
hsr->prune_timer.expires = jiffies + msecs_to_jiffies(PRUNE_PERIOD);
add_timer(&hsr->prune_timer);
@ -626,8 +548,4 @@ int hsr_dev_finalize(struct net_device *hsr_dev, struct net_device *slave[2],
register_hsr_master(hsr);
return 0;
fail:
restore_slaves(hsr_dev);
return res;
}

View file

@ -455,6 +455,7 @@ int hsr_get_node_data(struct hsr_priv *hsr,
u16 *if2_seq)
{
struct hsr_node *node;
struct net_device *slave;
unsigned long tdiff;
@ -491,8 +492,9 @@ int hsr_get_node_data(struct hsr_priv *hsr,
*if1_seq = node->seq_out[HSR_DEV_SLAVE_B];
*if2_seq = node->seq_out[HSR_DEV_SLAVE_A];
if ((node->AddrB_if != HSR_DEV_NONE) && hsr->slave[node->AddrB_if])
*addr_b_ifindex = hsr->slave[node->AddrB_if]->ifindex;
slave = hsr->slave[node->AddrB_if];
if ((node->AddrB_if != HSR_DEV_NONE) && slave)
*addr_b_ifindex = slave->ifindex;
else
*addr_b_ifindex = -1;

View file

@ -17,6 +17,7 @@
#include "hsr_device.h"
#include "hsr_netlink.h"
#include "hsr_framereg.h"
#include "hsr_slave.h"
/* List of all registered virtual HSR devices */
@ -124,22 +125,21 @@ static int hsr_netdev_notify(struct notifier_block *nb, unsigned long event,
if (dev == hsr->dev)
break;
if (dev == hsr->slave[0])
ether_addr_copy(hsr->dev->dev_addr,
hsr->slave[0]->dev_addr);
if (dev == hsr->slave[0]) {
ether_addr_copy(hsr->dev->dev_addr, dev->dev_addr);
call_netdevice_notifiers(NETDEV_CHANGEADDR, hsr->dev);
}
/* Make sure we recognize frames from ourselves in hsr_rcv() */
other_slave = hsr->slave[1];
res = hsr_create_self_node(&hsr->self_node_db,
hsr->dev->dev_addr,
hsr->slave[1] ?
hsr->slave[1]->dev_addr :
other_slave ?
other_slave->dev_addr :
hsr->dev->dev_addr);
if (res)
netdev_warn(hsr->dev,
"Could not update HSR node address.\n");
if (dev == hsr->slave[0])
call_netdevice_notifiers(NETDEV_CHANGEADDR, hsr->dev);
break;
case NETDEV_CHANGEMTU:
if (dev == hsr->dev)
@ -149,10 +149,14 @@ static int hsr_netdev_notify(struct notifier_block *nb, unsigned long event,
dev_set_mtu(hsr->dev, mtu_max);
break;
case NETDEV_UNREGISTER:
if (dev == hsr->slave[0])
if (dev == hsr->slave[0]) {
hsr->slave[0] = NULL;
if (dev == hsr->slave[1])
hsr_del_slave(hsr, 0);
}
if (dev == hsr->slave[1]) {
hsr->slave[1] = NULL;
hsr_del_slave(hsr, 1);
}
/* There should really be a way to set a new slave device... */

View file

@ -64,16 +64,28 @@ static int hsr_newlink(struct net *src_net, struct net_device *dev,
static int hsr_fill_info(struct sk_buff *skb, const struct net_device *dev)
{
struct hsr_priv *hsr;
struct net_device *slave;
int res;
hsr = netdev_priv(dev);
if (hsr->slave[0])
if (nla_put_u32(skb, IFLA_HSR_SLAVE1, hsr->slave[0]->ifindex))
goto nla_put_failure;
res = 0;
if (hsr->slave[1])
if (nla_put_u32(skb, IFLA_HSR_SLAVE2, hsr->slave[1]->ifindex))
goto nla_put_failure;
rcu_read_lock();
slave = hsr->slave[0];
if (slave)
res = nla_put_u32(skb, IFLA_HSR_SLAVE1, slave->ifindex);
rcu_read_unlock();
if (res)
goto nla_put_failure;
rcu_read_lock();
slave = hsr->slave[1];
if (slave)
res = nla_put_u32(skb, IFLA_HSR_SLAVE2, slave->ifindex);
rcu_read_unlock();
if (res)
goto nla_put_failure;
if (nla_put(skb, IFLA_HSR_SUPERVISION_ADDR, ETH_ALEN,
hsr->sup_multicast_addr) ||
@ -132,6 +144,7 @@ void hsr_nl_ringerror(struct hsr_priv *hsr, unsigned char addr[ETH_ALEN],
enum hsr_dev_idx dev_idx)
{
struct sk_buff *skb;
struct net_device *slave;
void *msg_head;
int res;
int ifindex;
@ -148,10 +161,14 @@ void hsr_nl_ringerror(struct hsr_priv *hsr, unsigned char addr[ETH_ALEN],
if (res < 0)
goto nla_put_failure;
if (hsr->slave[dev_idx])
ifindex = hsr->slave[dev_idx]->ifindex;
rcu_read_lock();
slave = hsr->slave[dev_idx];
if (slave)
ifindex = slave->ifindex;
else
ifindex = -1;
rcu_read_unlock();
res = nla_put_u32(skb, HSR_A_IFINDEX, ifindex);
if (res < 0)
goto nla_put_failure;
@ -215,7 +232,7 @@ static int hsr_get_node_status(struct sk_buff *skb_in, struct genl_info *info)
{
/* For receiving */
struct nlattr *na;
struct net_device *hsr_dev;
struct net_device *hsr_dev, *slave;
/* For sending */
struct sk_buff *skb_out;
@ -301,9 +318,11 @@ static int hsr_get_node_status(struct sk_buff *skb_in, struct genl_info *info)
res = nla_put_u16(skb_out, HSR_A_IF1_SEQ, hsr_node_if1_seq);
if (res < 0)
goto nla_put_failure;
if (hsr->slave[0])
res = nla_put_u32(skb_out, HSR_A_IF1_IFINDEX,
hsr->slave[0]->ifindex);
rcu_read_lock();
slave = hsr->slave[0];
if (slave)
res = nla_put_u32(skb_out, HSR_A_IF1_IFINDEX, slave->ifindex);
rcu_read_unlock();
if (res < 0)
goto nla_put_failure;
@ -313,9 +332,13 @@ static int hsr_get_node_status(struct sk_buff *skb_in, struct genl_info *info)
res = nla_put_u16(skb_out, HSR_A_IF2_SEQ, hsr_node_if2_seq);
if (res < 0)
goto nla_put_failure;
if (hsr->slave[1])
res = nla_put_u32(skb_out, HSR_A_IF2_IFINDEX,
hsr->slave[1]->ifindex);
rcu_read_lock();
slave = hsr->slave[1];
if (slave)
res = nla_put_u32(skb_out, HSR_A_IF2_IFINDEX, slave->ifindex);
rcu_read_unlock();
if (res < 0)
goto nla_put_failure;
genlmsg_end(skb_out, msg_head);
genlmsg_unicast(genl_info_net(info), skb_out, info->snd_portid);

View file

@ -11,10 +11,45 @@
#include "hsr_slave.h"
#include <linux/etherdevice.h>
#include <linux/if_arp.h>
#include "hsr_main.h"
#include "hsr_device.h"
#include "hsr_framereg.h"
static int check_slave_ok(struct net_device *dev)
{
/* Don't allow HSR on non-ethernet like devices */
if ((dev->flags & IFF_LOOPBACK) || (dev->type != ARPHRD_ETHER) ||
(dev->addr_len != ETH_ALEN)) {
netdev_info(dev, "Cannot use loopback or non-ethernet device as HSR slave.\n");
return -EINVAL;
}
/* Don't allow enslaving hsr devices */
if (is_hsr_master(dev)) {
netdev_info(dev, "Cannot create trees of HSR devices.\n");
return -EINVAL;
}
if (is_hsr_slave(dev)) {
netdev_info(dev, "This device is already a HSR slave.\n");
return -EINVAL;
}
if (dev->priv_flags & IFF_802_1Q_VLAN) {
netdev_info(dev, "HSR on top of VLAN is not yet supported in this driver.\n");
return -EINVAL;
}
/* HSR over bonded devices has not been tested, but I'm not sure it
* won't work...
*/
return 0;
}
static struct sk_buff *hsr_pull_tag(struct sk_buff *skb)
{
struct hsr_tag *hsr_tag;
@ -241,3 +276,59 @@ forward:
return RX_HANDLER_CONSUMED;
}
int hsr_add_slave(struct hsr_priv *hsr, struct net_device *dev, int idx)
{
int res;
dev_hold(dev);
res = check_slave_ok(dev);
if (res)
goto fail;
res = dev_set_promiscuity(dev, 1);
if (res)
goto fail;
res = netdev_rx_handler_register(dev, hsr_handle_frame, hsr);
if (res)
goto fail_rx_handler;
hsr->slave[idx] = dev;
/* Set required header length */
if (dev->hard_header_len + HSR_HLEN > hsr->dev->hard_header_len)
hsr->dev->hard_header_len = dev->hard_header_len + HSR_HLEN;
dev_set_mtu(hsr->dev, hsr_get_max_mtu(hsr));
return 0;
fail_rx_handler:
dev_set_promiscuity(dev, -1);
fail:
dev_put(dev);
return res;
}
void hsr_del_slave(struct hsr_priv *hsr, int idx)
{
struct net_device *slave;
slave = hsr->slave[idx];
hsr->slave[idx] = NULL;
netdev_update_features(hsr->dev);
dev_set_mtu(hsr->dev, hsr_get_max_mtu(hsr));
if (slave) {
netdev_rx_handler_unregister(slave);
dev_set_promiscuity(slave, -1);
}
synchronize_rcu();
dev_put(slave);
}

View file

@ -14,7 +14,10 @@
#include <linux/skbuff.h>
#include <linux/netdevice.h>
#include "hsr_main.h"
int hsr_add_slave(struct hsr_priv *hsr, struct net_device *dev, int idx);
void hsr_del_slave(struct hsr_priv *hsr, int idx);
rx_handler_result_t hsr_handle_frame(struct sk_buff **pskb);
#endif /* __HSR_SLAVE_H */