Commit d87d6f44 authored by Guenter Roeck's avatar Guenter Roeck Committed by David S. Miller
Browse files

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: default avatarGuenter Roeck <linux@roeck-us.net>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 92bf2008

net/dsa/dsa.c

+3 −7
Original line number Diff line number Diff line
@@ -314,19 +314,15 @@ dsa_switch_setup(struct dsa_switch_tree *dst, int index, 
	 * 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

net/dsa/dsa_priv.h

+2 −3
Original line number Diff line number Diff line
@@ -53,8 +53,7 @@ extern char dsa_driver_version[]; 
/* 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 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);

net/dsa/slave.c

+8 −7
Original line number Diff line number Diff line
@@ -605,8 +605,7 @@ int dsa_slave_resume(struct net_device *slave_dev) 
	return 0;

}



struct net_device *

dsa_slave_create(struct dsa_switch *ds, struct device *parent,

int dsa_slave_create(struct dsa_switch *ds, struct device *parent,

		     int port, char *name)

{

	struct net_device *master = ds->dst->master_netdev;
@@ -617,7 +616,7 @@ dsa_slave_create(struct dsa_switch *ds, struct device *parent, 
	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 @@ dsa_slave_create(struct dsa_switch *ds, struct device *parent, 
	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;

}

CRA Git | Maintained and supported by SUSTech CRA and CCSE