@@ -221,40 +221,46 @@ struct net_device synchronization rules
Note: netif_running() is guaranteed false
ndo_do_ioctl:
- Synchronization: rtnl_lock() semaphore.
+ Synchronization: rtnl_lock() semaphore. In addition, netdev instance
+ lock if the driver implements shaper API.
Context: process
- This is only called by network subsystems internally,
- not by user space calling ioctl as it was in before
- linux-5.14.
+ This is only called by network subsystems internally,
+ not by user space calling ioctl as it was in before
+ linux-5.14.
ndo_siocbond:
- Synchronization: rtnl_lock() semaphore.
+ Synchronization: rtnl_lock() semaphore. In addition, netdev instance
+ lock if the driver implements shaper API.
Context: process
- Used by the bonding driver for the SIOCBOND family of
- ioctl commands.
+ Used by the bonding driver for the SIOCBOND family of
+ ioctl commands.
ndo_siocwandev:
- Synchronization: rtnl_lock() semaphore.
+ Synchronization: rtnl_lock() semaphore. In addition, netdev instance
+ lock if the driver implements shaper API.
Context: process
Used by the drivers/net/wan framework to handle
the SIOCWANDEV ioctl with the if_settings structure.
ndo_siocdevprivate:
- Synchronization: rtnl_lock() semaphore.
+ Synchronization: rtnl_lock() semaphore. In addition, netdev instance
+ lock if the driver implements shaper API.
Context: process
This is used to implement SIOCDEVPRIVATE ioctl helpers.
These should not be added to new drivers, so don't use.
ndo_eth_ioctl:
- Synchronization: rtnl_lock() semaphore.
+ Synchronization: rtnl_lock() semaphore. In addition, netdev instance
+ lock if the driver implements shaper API.
Context: process
ndo_get_stats:
- Synchronization: rtnl_lock() semaphore, or RCU.
+ Synchronization: RCU (can be called concurrently with the stats
+ update path).
Context: atomic (can't sleep under RCU)
ndo_setup_tc:
@@ -858,7 +858,6 @@ static int bond_check_dev_link(struct bonding *bond,
struct net_device *slave_dev, int reporting)
{
const struct net_device_ops *slave_ops = slave_dev->netdev_ops;
- int (*ioctl)(struct net_device *, struct ifreq *, int);
struct ifreq ifr;
struct mii_ioctl_data *mii;
@@ -874,8 +873,7 @@ static int bond_check_dev_link(struct bonding *bond,
BMSR_LSTATUS : 0;
/* Ethtool can't be used, fallback to MII ioctls. */
- ioctl = slave_ops->ndo_eth_ioctl;
- if (ioctl) {
+ if (slave_ops->ndo_eth_ioctl) {
/* TODO: set pointer to correct ioctl on a per team member
* bases to make this more efficient. that is, once
* we determine the correct ioctl, we will always
@@ -891,9 +889,10 @@ static int bond_check_dev_link(struct bonding *bond,
/* Yes, the mii is overlaid on the ifreq.ifr_ifru */
strscpy_pad(ifr.ifr_name, slave_dev->name, IFNAMSIZ);
mii = if_mii(&ifr);
- if (ioctl(slave_dev, &ifr, SIOCGMIIPHY) == 0) {
+
+ if (dev_eth_ioctl(slave_dev, &ifr, SIOCGMIIPHY) == 0) {
mii->reg_num = MII_BMSR;
- if (ioctl(slave_dev, &ifr, SIOCGMIIREG) == 0)
+ if (dev_eth_ioctl(slave_dev, &ifr, SIOCGMIIREG) == 0)
return mii->val_out & BMSR_LSTATUS;
}
}
@@ -4159,6 +4159,8 @@ int put_user_ifreq(struct ifreq *ifr, void __user *arg);
int dev_ioctl(struct net *net, unsigned int cmd, struct ifreq *ifr,
void __user *data, bool *need_copyout);
int dev_ifconf(struct net *net, struct ifconf __user *ifc);
+int dev_eth_ioctl(struct net_device *dev,
+ struct ifreq *ifr, unsigned int cmd);
int generic_hwtstamp_get_lower(struct net_device *dev,
struct kernel_hwtstamp_config *kernel_cfg);
int generic_hwtstamp_set_lower(struct net_device *dev,
@@ -377,7 +377,6 @@ static int vlan_hwtstamp_set(struct net_device *dev,
static int vlan_dev_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
{
struct net_device *real_dev = vlan_dev_priv(dev)->real_dev;
- const struct net_device_ops *ops = real_dev->netdev_ops;
struct ifreq ifrr;
int err = -EOPNOTSUPP;
@@ -388,8 +387,7 @@ static int vlan_dev_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
case SIOCGMIIPHY:
case SIOCGMIIREG:
case SIOCSMIIREG:
- if (netif_device_present(real_dev) && ops->ndo_eth_ioctl)
- err = ops->ndo_eth_ioctl(real_dev, &ifrr, cmd);
+ err = dev_eth_ioctl(real_dev, &ifrr, cmd);
break;
}
@@ -240,19 +240,23 @@ int net_hwtstamp_validate(const struct kernel_hwtstamp_config *cfg)
return 0;
}
-static int dev_eth_ioctl(struct net_device *dev,
- struct ifreq *ifr, unsigned int cmd)
+int dev_eth_ioctl(struct net_device *dev,
+ struct ifreq *ifr, unsigned int cmd)
{
const struct net_device_ops *ops = dev->netdev_ops;
+ int ret = -ENODEV;
if (!ops->ndo_eth_ioctl)
return -EOPNOTSUPP;
- if (!netif_device_present(dev))
- return -ENODEV;
+ netdev_lock_ops(dev);
+ if (netif_device_present(dev))
+ ret = ops->ndo_eth_ioctl(dev, ifr, cmd);
+ netdev_unlock_ops(dev);
- return ops->ndo_eth_ioctl(dev, ifr, cmd);
+ return ret;
}
+EXPORT_SYMBOL(dev_eth_ioctl);
/**
* dev_get_hwtstamp_phylib() - Get hardware timestamping settings of NIC
@@ -504,10 +508,14 @@ static int dev_siocbond(struct net_device *dev,
const struct net_device_ops *ops = dev->netdev_ops;
if (ops->ndo_siocbond) {
+ int ret = -ENODEV;
+
+ netdev_lock_ops(dev);
if (netif_device_present(dev))
- return ops->ndo_siocbond(dev, ifr, cmd);
- else
- return -ENODEV;
+ ret = ops->ndo_siocbond(dev, ifr, cmd);
+ netdev_unlock_ops(dev);
+
+ return ret;
}
return -EOPNOTSUPP;
@@ -519,10 +527,14 @@ static int dev_siocdevprivate(struct net_device *dev, struct ifreq *ifr,
const struct net_device_ops *ops = dev->netdev_ops;
if (ops->ndo_siocdevprivate) {
+ int ret = -ENODEV;
+
+ netdev_lock_ops(dev);
if (netif_device_present(dev))
- return ops->ndo_siocdevprivate(dev, ifr, data, cmd);
- else
- return -ENODEV;
+ ret = ops->ndo_siocdevprivate(dev, ifr, data, cmd);
+ netdev_unlock_ops(dev);
+
+ return ret;
}
return -EOPNOTSUPP;
@@ -533,10 +545,14 @@ static int dev_siocwandev(struct net_device *dev, struct if_settings *ifs)
const struct net_device_ops *ops = dev->netdev_ops;
if (ops->ndo_siocwandev) {
+ int ret = -ENODEV;
+
+ netdev_lock_ops(dev);
if (netif_device_present(dev))
- return ops->ndo_siocwandev(dev, ifs);
- else
- return -ENODEV;
+ ret = ops->ndo_siocwandev(dev, ifs);
+ netdev_unlock_ops(dev);
+
+ return ret;
}
return -EOPNOTSUPP;
@@ -139,8 +139,10 @@ static int ieee802154_dev_ioctl(struct sock *sk, struct ifreq __user *arg,
if (!dev)
return -ENODEV;
+ netdev_lock_ops(dev);
if (dev->type == ARPHRD_IEEE802154 && dev->netdev_ops->ndo_do_ioctl)
ret = dev->netdev_ops->ndo_do_ioctl(dev, &ifr, cmd);
+ netdev_unlock_ops(dev);
if (!ret && put_user_ifreq(&ifr, arg))
ret = -EFAULT;
@@ -246,8 +246,10 @@ static int phonet_device_autoconf(struct net_device *dev)
if (!dev->netdev_ops->ndo_siocdevprivate)
return -EOPNOTSUPP;
+ netdev_lock_ops(dev);
ret = dev->netdev_ops->ndo_siocdevprivate(dev, (struct ifreq *)&req,
NULL, SIOCPNGAUTOCONF);
+ netdev_unlock_ops(dev);
if (ret < 0)
return ret;
Convert all ndo_eth_ioctl invocations to dev_eth_ioctl which does the locking. Reflow some of the dev_siocxxx to drop else clause. Fix tabs vs spaces in neighboring lines while at it.. Remove rtnl_lock from ndo_get_stats and clarify that read path can race with the write path. Still shaper-only drivers (iavf/netdevim). Cc: Saeed Mahameed <saeed@kernel.org> Signed-off-by: Stanislav Fomichev <sdf@fomichev.me> --- Documentation/networking/netdevices.rst | 28 +++++++++------- drivers/net/bonding/bond_main.c | 9 +++-- include/linux/netdevice.h | 2 ++ net/8021q/vlan_dev.c | 4 +-- net/core/dev_ioctl.c | 44 +++++++++++++++++-------- net/ieee802154/socket.c | 2 ++ net/phonet/pn_dev.c | 2 ++ 7 files changed, 58 insertions(+), 33 deletions(-)