net: dsa: Ensure that port array elements are initialized before being used
A network device notifier can be called for one or more of the created
slave devices before all slave devices have been registered. This can
result in a mismatch between ds->phys_port_mask and the registered devices
by the time the call is made, and it can result in a slave device being
added to a bridge before its entry in ds->ports[] has been initialized.
Rework the initialization code to initialize entries in ds->ports[] in
dsa_slave_create. With this change, dsa_slave_create no longer needs
to return slave_dev but can return an error code instead.
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/dsa/dsa.c b/net/dsa/dsa.c
index 2173402..fc18131 100644
--- a/net/dsa/dsa.c
+++ b/net/dsa/dsa.c
@@ -314,19 +314,15 @@
* Create network devices for physical switch ports.
*/
for (i = 0; i < DSA_MAX_PORTS; i++) {
- struct net_device *slave_dev;
-
if (!(ds->phys_port_mask & (1 << i)))
continue;
- slave_dev = dsa_slave_create(ds, parent, i, pd->port_names[i]);
- if (slave_dev == NULL) {
+ ret = dsa_slave_create(ds, parent, i, pd->port_names[i]);
+ if (ret < 0) {
netdev_err(dst->master_netdev, "[%d]: can't create dsa slave device for port %d(%s)\n",
index, i, pd->port_names[i]);
- continue;
+ ret = 0;
}
-
- ds->ports[i] = slave_dev;
}
#ifdef CONFIG_NET_DSA_HWMON
diff --git a/net/dsa/dsa_priv.h b/net/dsa/dsa_priv.h
index dc9756d..7eb1a6a 100644
--- a/net/dsa/dsa_priv.h
+++ b/net/dsa/dsa_priv.h
@@ -53,9 +53,8 @@
/* slave.c */
extern const struct dsa_device_ops notag_netdev_ops;
void dsa_slave_mii_bus_init(struct dsa_switch *ds);
-struct net_device *dsa_slave_create(struct dsa_switch *ds,
- struct device *parent,
- int port, char *name);
+int dsa_slave_create(struct dsa_switch *ds, struct device *parent,
+ int port, char *name);
int dsa_slave_suspend(struct net_device *slave_dev);
int dsa_slave_resume(struct net_device *slave_dev);
diff --git a/net/dsa/slave.c b/net/dsa/slave.c
index f23dead..5be4c92 100644
--- a/net/dsa/slave.c
+++ b/net/dsa/slave.c
@@ -605,9 +605,8 @@
return 0;
}
-struct net_device *
-dsa_slave_create(struct dsa_switch *ds, struct device *parent,
- int port, char *name)
+int dsa_slave_create(struct dsa_switch *ds, struct device *parent,
+ int port, char *name)
{
struct net_device *master = ds->dst->master_netdev;
struct net_device *slave_dev;
@@ -617,7 +616,7 @@
slave_dev = alloc_netdev(sizeof(struct dsa_slave_priv), name,
NET_NAME_UNKNOWN, ether_setup);
if (slave_dev == NULL)
- return slave_dev;
+ return -ENOMEM;
slave_dev->features = master->vlan_features;
slave_dev->ethtool_ops = &dsa_slave_ethtool_ops;
@@ -667,19 +666,21 @@
ret = dsa_slave_phy_setup(p, slave_dev);
if (ret) {
free_netdev(slave_dev);
- return NULL;
+ return ret;
}
+ ds->ports[port] = slave_dev;
ret = register_netdev(slave_dev);
if (ret) {
netdev_err(master, "error %d registering interface %s\n",
ret, slave_dev->name);
phy_disconnect(p->phy);
+ ds->ports[port] = NULL;
free_netdev(slave_dev);
- return NULL;
+ return ret;
}
netif_carrier_off(slave_dev);
- return slave_dev;
+ return 0;
}