net/core/dev_ioctl.c - third_party/kernel - Git at Google

 // SPDX-License-Identifier: GPL-2.0
 #include <linux/kmod.h>
 #include <linux/netdevice.h>
 #include <linux/inetdevice.h>
 #include <linux/etherdevice.h>
 #include <linux/rtnetlink.h>
 #include <linux/net_tstamp.h>
 #include <linux/wireless.h>
 #include <linux/if_bridge.h>
 #include <net/dsa.h>
 #include <net/wext.h>

 /*
  *	Map an interface index to its name (SIOCGIFNAME)
  */

 /*
  *	We need this ioctl for efficient implementation of the
  *	if_indextoname() function required by the IPv6 API.  Without
  *	it, we would have to search all the interfaces to find a
  *	match.  --pb
  */

 static int dev_ifname(struct net *net, struct ifreq *ifr)
 {
 	ifr->ifr_name[IFNAMSIZ-1] = 0;
 	return netdev_get_name(net, ifr->ifr_name, ifr->ifr_ifindex);
 }

 /*
  *	Perform a SIOCGIFCONF call. This structure will change
  *	size eventually, and there is nothing I can do about it.
  *	Thus we will need a 'compatibility mode'.
  */
 int dev_ifconf(struct net *net, struct ifconf __user *uifc)
 {
 	struct net_device *dev;
 	void __user *pos;
 	size_t size;
 	int len, total = 0, done;

 	/* both the ifconf and the ifreq structures are slightly different */
 	if (in_compat_syscall()) {
 		struct compat_ifconf ifc32;

 		if (copy_from_user(&ifc32, uifc, sizeof(struct compat_ifconf)))
 			return -EFAULT;

 		pos = compat_ptr(ifc32.ifcbuf);
 		len = ifc32.ifc_len;
 		size = sizeof(struct compat_ifreq);
 	} else {
 		struct ifconf ifc;

 		if (copy_from_user(&ifc, uifc, sizeof(struct ifconf)))
 			return -EFAULT;

 		pos = ifc.ifc_buf;
 		len = ifc.ifc_len;
 		size = sizeof(struct ifreq);
 	}

 	/* Loop over the interfaces, and write an info block for each. */
 	rtnl_lock();
 	for_each_netdev(net, dev) {
 		if (!pos)
 			done = inet_gifconf(dev, NULL, 0, size);
 		else
 			done = inet_gifconf(dev, pos + total,
 					    len - total, size);
 		if (done < 0) {
 			rtnl_unlock();
 			return -EFAULT;
 		}
 		total += done;
 	}
 	rtnl_unlock();

 	return put_user(total, &uifc->ifc_len);
 }

 static int dev_getifmap(struct net_device *dev, struct ifreq *ifr)
 {
 	struct ifmap *ifmap = &ifr->ifr_map;

 	if (in_compat_syscall()) {
 		struct compat_ifmap *cifmap = (struct compat_ifmap *)ifmap;

 		cifmap->mem_start = dev->mem_start;
 		cifmap->mem_end   = dev->mem_end;
 		cifmap->base_addr = dev->base_addr;
 		cifmap->irq       = dev->irq;
 		cifmap->dma       = dev->dma;
 		cifmap->port      = dev->if_port;

 		return 0;
 	}

 	ifmap->mem_start  = dev->mem_start;
 	ifmap->mem_end    = dev->mem_end;
 	ifmap->base_addr  = dev->base_addr;
 	ifmap->irq        = dev->irq;
 	ifmap->dma        = dev->dma;
 	ifmap->port       = dev->if_port;

 	return 0;
 }

 static int dev_setifmap(struct net_device *dev, struct ifreq *ifr)
 {
 	struct compat_ifmap *cifmap = (struct compat_ifmap *)&ifr->ifr_map;

 	if (!dev->netdev_ops->ndo_set_config)
 		return -EOPNOTSUPP;

 	if (in_compat_syscall()) {
 		struct ifmap ifmap = {
 			.mem_start  = cifmap->mem_start,
 			.mem_end    = cifmap->mem_end,
 			.base_addr  = cifmap->base_addr,
 			.irq        = cifmap->irq,
 			.dma        = cifmap->dma,
 			.port       = cifmap->port,
 		};

 		return dev->netdev_ops->ndo_set_config(dev, &ifmap);
 	}

 	return dev->netdev_ops->ndo_set_config(dev, &ifr->ifr_map);
 }

 /*
  *	Perform the SIOCxIFxxx calls, inside rcu_read_lock()
  */
 static int dev_ifsioc_locked(struct net *net, struct ifreq *ifr, unsigned int cmd)
 {
 	int err;
 	struct net_device *dev = dev_get_by_name_rcu(net, ifr->ifr_name);

 	if (!dev)
 		return -ENODEV;

 	switch (cmd) {
 	case SIOCGIFFLAGS:	/* Get interface flags */
 		ifr->ifr_flags = (short) dev_get_flags(dev);
 		return 0;

 	case SIOCGIFMETRIC:	/* Get the metric on the interface
 				   (currently unused) */
 		ifr->ifr_metric = 0;
 		return 0;

 	case SIOCGIFMTU:	/* Get the MTU of a device */
 		ifr->ifr_mtu = dev->mtu;
 		return 0;

 	case SIOCGIFSLAVE:
 		err = -EINVAL;
 		break;

 	case SIOCGIFMAP:
 		return dev_getifmap(dev, ifr);

 	case SIOCGIFINDEX:
 		ifr->ifr_ifindex = dev->ifindex;
 		return 0;

 	case SIOCGIFTXQLEN:
 		ifr->ifr_qlen = dev->tx_queue_len;
 		return 0;

 	default:
 		/* dev_ioctl() should ensure this case
 		 * is never reached
 		 */
 		WARN_ON(1);
 		err = -ENOTTY;
 		break;

 	}
 	return err;
 }

 static int net_hwtstamp_validate(struct ifreq *ifr)
 {
 	struct hwtstamp_config cfg;
 	enum hwtstamp_tx_types tx_type;
 	enum hwtstamp_rx_filters rx_filter;
 	int tx_type_valid = 0;
 	int rx_filter_valid = 0;

 	if (copy_from_user(&cfg, ifr->ifr_data, sizeof(cfg)))
 		return -EFAULT;

 	if (cfg.flags) /* reserved for future extensions */
 		return -EINVAL;

 	tx_type = cfg.tx_type;
 	rx_filter = cfg.rx_filter;

 	switch (tx_type) {
 	case HWTSTAMP_TX_OFF:
 	case HWTSTAMP_TX_ON:
 	case HWTSTAMP_TX_ONESTEP_SYNC:
 	case HWTSTAMP_TX_ONESTEP_P2P:
 		tx_type_valid = 1;
 		break;
 	case __HWTSTAMP_TX_CNT:
 		/* not a real value */
 		break;
 	}

 	switch (rx_filter) {
 	case HWTSTAMP_FILTER_NONE:
 	case HWTSTAMP_FILTER_ALL:
 	case HWTSTAMP_FILTER_SOME:
 	case HWTSTAMP_FILTER_PTP_V1_L4_EVENT:
 	case HWTSTAMP_FILTER_PTP_V1_L4_SYNC:
 	case HWTSTAMP_FILTER_PTP_V1_L4_DELAY_REQ:
 	case HWTSTAMP_FILTER_PTP_V2_L4_EVENT:
 	case HWTSTAMP_FILTER_PTP_V2_L4_SYNC:
 	case HWTSTAMP_FILTER_PTP_V2_L4_DELAY_REQ:
 	case HWTSTAMP_FILTER_PTP_V2_L2_EVENT:
 	case HWTSTAMP_FILTER_PTP_V2_L2_SYNC:
 	case HWTSTAMP_FILTER_PTP_V2_L2_DELAY_REQ:
 	case HWTSTAMP_FILTER_PTP_V2_EVENT:
 	case HWTSTAMP_FILTER_PTP_V2_SYNC:
 	case HWTSTAMP_FILTER_PTP_V2_DELAY_REQ:
 	case HWTSTAMP_FILTER_NTP_ALL:
 		rx_filter_valid = 1;
 		break;
 	case __HWTSTAMP_FILTER_CNT:
 		/* not a real value */
 		break;
 	}

 	if (!tx_type_valid || !rx_filter_valid)
 		return -ERANGE;

 	return 0;
 }

 static int dev_eth_ioctl(struct net_device *dev,
 			 struct ifreq *ifr, unsigned int cmd)
 {
 	const struct net_device_ops *ops = dev->netdev_ops;
 	int err;

 	err = dsa_ndo_eth_ioctl(dev, ifr, cmd);
 	if (err == 0 || err != -EOPNOTSUPP)
 		return err;

 	if (ops->ndo_eth_ioctl) {
 		if (netif_device_present(dev))
 			err = ops->ndo_eth_ioctl(dev, ifr, cmd);
 		else
 			err = -ENODEV;
 	}

 	return err;
 }

 static int dev_siocbond(struct net_device *dev,
 			struct ifreq *ifr, unsigned int cmd)
 {
 	const struct net_device_ops *ops = dev->netdev_ops;

 	if (ops->ndo_siocbond) {
 		if (netif_device_present(dev))
 			return ops->ndo_siocbond(dev, ifr, cmd);
 		else
 			return -ENODEV;
 	}

 	return -EOPNOTSUPP;
 }

 static int dev_siocdevprivate(struct net_device *dev, struct ifreq *ifr,
 			      void __user *data, unsigned int cmd)
 {
 	const struct net_device_ops *ops = dev->netdev_ops;

 	if (ops->ndo_siocdevprivate) {
 		if (netif_device_present(dev))
 			return ops->ndo_siocdevprivate(dev, ifr, data, cmd);
 		else
 			return -ENODEV;
 	}

 	return -EOPNOTSUPP;
 }

 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) {
 		if (netif_device_present(dev))
 			return ops->ndo_siocwandev(dev, ifs);
 		else
 			return -ENODEV;
 	}

 	return -EOPNOTSUPP;
 }

 /*
  *	Perform the SIOCxIFxxx calls, inside rtnl_lock()
  */
 static int dev_ifsioc(struct net *net, struct ifreq *ifr, void __user *data,
 		      unsigned int cmd)
 {
 	int err;
 	struct net_device *dev = __dev_get_by_name(net, ifr->ifr_name);
 	const struct net_device_ops *ops;

 	if (!dev)
 		return -ENODEV;

 	ops = dev->netdev_ops;

 	switch (cmd) {
 	case SIOCSIFFLAGS:	/* Set interface flags */
 		return dev_change_flags(dev, ifr->ifr_flags, NULL);

 	case SIOCSIFMETRIC:	/* Set the metric on the interface
 				   (currently unused) */
 		return -EOPNOTSUPP;

 	case SIOCSIFMTU:	/* Set the MTU of a device */
 		return dev_set_mtu(dev, ifr->ifr_mtu);

 	case SIOCSIFHWADDR:
 		if (dev->addr_len > sizeof(struct sockaddr))
 			return -EINVAL;
 		return dev_set_mac_address_user(dev, &ifr->ifr_hwaddr, NULL);

 	case SIOCSIFHWBROADCAST:
 		if (ifr->ifr_hwaddr.sa_family != dev->type)
 			return -EINVAL;
 		memcpy(dev->broadcast, ifr->ifr_hwaddr.sa_data,
 		       min(sizeof(ifr->ifr_hwaddr.sa_data),
 			   (size_t)dev->addr_len));
 		call_netdevice_notifiers(NETDEV_CHANGEADDR, dev);
 		return 0;

 	case SIOCSIFMAP:
 		return dev_setifmap(dev, ifr);

 	case SIOCADDMULTI:
 		if (!ops->ndo_set_rx_mode ||
 		    ifr->ifr_hwaddr.sa_family != AF_UNSPEC)
 			return -EINVAL;
 		if (!netif_device_present(dev))
 			return -ENODEV;
 		return dev_mc_add_global(dev, ifr->ifr_hwaddr.sa_data);

 	case SIOCDELMULTI:
 		if (!ops->ndo_set_rx_mode ||
 		    ifr->ifr_hwaddr.sa_family != AF_UNSPEC)
 			return -EINVAL;
 		if (!netif_device_present(dev))
 			return -ENODEV;
 		return dev_mc_del_global(dev, ifr->ifr_hwaddr.sa_data);

 	case SIOCSIFTXQLEN:
 		if (ifr->ifr_qlen < 0)
 			return -EINVAL;
 		return dev_change_tx_queue_len(dev, ifr->ifr_qlen);

 	case SIOCSIFNAME:
 		ifr->ifr_newname[IFNAMSIZ-1] = '\0';
 		return dev_change_name(dev, ifr->ifr_newname);

 	case SIOCWANDEV:
 		return dev_siocwandev(dev, &ifr->ifr_settings);

 	case SIOCBRADDIF:
 	case SIOCBRDELIF:
 		if (!netif_device_present(dev))
 			return -ENODEV;
 		if (!netif_is_bridge_master(dev))
 			return -EOPNOTSUPP;
 		dev_hold(dev);
 		rtnl_unlock();
 		err = br_ioctl_call(net, netdev_priv(dev), cmd, ifr, NULL);
 		dev_put(dev);
 		rtnl_lock();
 		return err;

 	case SIOCSHWTSTAMP:
 		err = net_hwtstamp_validate(ifr);
 		if (err)
 			return err;
 		fallthrough;

 	/*
 	 *	Unknown or private ioctl
 	 */
 	default:
 		if (cmd >= SIOCDEVPRIVATE &&
 		    cmd <= SIOCDEVPRIVATE + 15)
 			return dev_siocdevprivate(dev, ifr, data, cmd);

 		if (cmd == SIOCGMIIPHY ||
 		    cmd == SIOCGMIIREG ||
 		    cmd == SIOCSMIIREG ||
 		    cmd == SIOCSHWTSTAMP ||
 		    cmd == SIOCGHWTSTAMP) {
 			err = dev_eth_ioctl(dev, ifr, cmd);
 		} else if (cmd == SIOCBONDENSLAVE ||
 		    cmd == SIOCBONDRELEASE ||
 		    cmd == SIOCBONDSETHWADDR ||
 		    cmd == SIOCBONDSLAVEINFOQUERY ||
 		    cmd == SIOCBONDINFOQUERY ||
 		    cmd == SIOCBONDCHANGEACTIVE) {
 			err = dev_siocbond(dev, ifr, cmd);
 		} else
 			err = -EINVAL;

 	}
 	return err;
 }

 /**
  *	dev_load 	- load a network module
  *	@net: the applicable net namespace
  *	@name: name of interface
  *
  *	If a network interface is not present and the process has suitable
  *	privileges this function loads the module. If module loading is not
  *	available in this kernel then it becomes a nop.
  */

 void dev_load(struct net *net, const char *name)
 {
 	struct net_device *dev;
 	int no_module;

 	rcu_read_lock();
 	dev = dev_get_by_name_rcu(net, name);
 	rcu_read_unlock();

 	no_module = !dev;
 	if (no_module && capable(CAP_NET_ADMIN))
 		no_module = request_module("netdev-%s", name);
 	if (no_module && capable(CAP_SYS_MODULE))
 		request_module("%s", name);
 }
 EXPORT_SYMBOL(dev_load);

 /*
  *	This function handles all "interface"-type I/O control requests. The actual
  *	'doing' part of this is dev_ifsioc above.
  */

 /**
  *	dev_ioctl	-	network device ioctl
  *	@net: the applicable net namespace
  *	@cmd: command to issue
  *	@ifr: pointer to a struct ifreq in user space
  *	@need_copyout: whether or not copy_to_user() should be called
  *
  *	Issue ioctl functions to devices. This is normally called by the
  *	user space syscall interfaces but can sometimes be useful for
  *	other purposes. The return value is the return from the syscall if
  *	positive or a negative errno code on error.
  */

 int dev_ioctl(struct net *net, unsigned int cmd, struct ifreq *ifr,
 	      void __user *data, bool *need_copyout)
 {
 	int ret;
 	char *colon;

 	if (need_copyout)
 		*need_copyout = true;
 	if (cmd == SIOCGIFNAME)
 		return dev_ifname(net, ifr);

 	ifr->ifr_name[IFNAMSIZ-1] = 0;

 	colon = strchr(ifr->ifr_name, ':');
 	if (colon)
 		*colon = 0;

 	/*
 	 *	See which interface the caller is talking about.
 	 */

 	switch (cmd) {
 	case SIOCGIFHWADDR:
 		dev_load(net, ifr->ifr_name);
 		ret = dev_get_mac_address(&ifr->ifr_hwaddr, net, ifr->ifr_name);
 		if (colon)
 			*colon = ':';
 		return ret;
 	/*
 	 *	These ioctl calls:
 	 *	- can be done by all.
 	 *	- atomic and do not require locking.
 	 *	- return a value
 	 */
 	case SIOCGIFFLAGS:
 	case SIOCGIFMETRIC:
 	case SIOCGIFMTU:
 	case SIOCGIFSLAVE:
 	case SIOCGIFMAP:
 	case SIOCGIFINDEX:
 	case SIOCGIFTXQLEN:
 		dev_load(net, ifr->ifr_name);
 		rcu_read_lock();
 		ret = dev_ifsioc_locked(net, ifr, cmd);
 		rcu_read_unlock();
 		if (colon)
 			*colon = ':';
 		return ret;

 	case SIOCETHTOOL:
 		dev_load(net, ifr->ifr_name);
 		rtnl_lock();
 		ret = dev_ethtool(net, ifr, data);
 		rtnl_unlock();
 		if (colon)
 			*colon = ':';
 		return ret;

 	/*
 	 *	These ioctl calls:
 	 *	- require superuser power.
 	 *	- require strict serialization.
 	 *	- return a value
 	 */
 	case SIOCGMIIPHY:
 	case SIOCGMIIREG:
 	case SIOCSIFNAME:
 		dev_load(net, ifr->ifr_name);
 		if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
 			return -EPERM;
 		rtnl_lock();
 		ret = dev_ifsioc(net, ifr, data, cmd);
 		rtnl_unlock();
 		if (colon)
 			*colon = ':';
 		return ret;

 	/*
 	 *	These ioctl calls:
 	 *	- require superuser power.
 	 *	- require strict serialization.
 	 *	- do not return a value
 	 */
 	case SIOCSIFMAP:
 	case SIOCSIFTXQLEN:
 		if (!capable(CAP_NET_ADMIN))
 			return -EPERM;
 		fallthrough;
 	/*
 	 *	These ioctl calls:
 	 *	- require local superuser power.
 	 *	- require strict serialization.
 	 *	- do not return a value
 	 */
 	case SIOCSIFFLAGS:
 	case SIOCSIFMETRIC:
 	case SIOCSIFMTU:
 	case SIOCSIFHWADDR:
 	case SIOCSIFSLAVE:
 	case SIOCADDMULTI:
 	case SIOCDELMULTI:
 	case SIOCSIFHWBROADCAST:
 	case SIOCSMIIREG:
 	case SIOCBONDENSLAVE:
 	case SIOCBONDRELEASE:
 	case SIOCBONDSETHWADDR:
 	case SIOCBONDCHANGEACTIVE:
 	case SIOCBRADDIF:
 	case SIOCBRDELIF:
 	case SIOCSHWTSTAMP:
 		if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
 			return -EPERM;
 		fallthrough;
 	case SIOCBONDSLAVEINFOQUERY:
 	case SIOCBONDINFOQUERY:
 		dev_load(net, ifr->ifr_name);
 		rtnl_lock();
 		ret = dev_ifsioc(net, ifr, data, cmd);
 		rtnl_unlock();
 		if (need_copyout)
 			*need_copyout = false;
 		return ret;

 	case SIOCGIFMEM:
 		/* Get the per device memory space. We can add this but
 		 * currently do not support it */
 	case SIOCSIFMEM:
 		/* Set the per device memory buffer space.
 		 * Not applicable in our case */
 	case SIOCSIFLINK:
 		return -ENOTTY;

 	/*
 	 *	Unknown or private ioctl.
 	 */
 	default:
 		if (cmd == SIOCWANDEV ||
 		    cmd == SIOCGHWTSTAMP ||
 		    (cmd >= SIOCDEVPRIVATE &&
 		     cmd <= SIOCDEVPRIVATE + 15)) {
 			dev_load(net, ifr->ifr_name);
 			rtnl_lock();
 			ret = dev_ifsioc(net, ifr, data, cmd);
 			rtnl_unlock();
 			return ret;
 		}
 		return -ENOTTY;
 	}
 }
	// SPDX-License-Identifier: GPL-2.0
	#include <linux/kmod.h>
	#include <linux/netdevice.h>
	#include <linux/inetdevice.h>
	#include <linux/etherdevice.h>
	#include <linux/rtnetlink.h>
	#include <linux/net_tstamp.h>
	#include <linux/wireless.h>
	#include <linux/if_bridge.h>
	#include <net/dsa.h>
	#include <net/wext.h>

	/*
	* Map an interface index to its name (SIOCGIFNAME)
	*/

	/*
	* We need this ioctl for efficient implementation of the
	* if_indextoname() function required by the IPv6 API. Without
	* it, we would have to search all the interfaces to find a
	* match. --pb
	*/

	static int dev_ifname(struct net net, struct ifreq ifr)
	{
	ifr->ifr_name[IFNAMSIZ-1] = 0;
	return netdev_get_name(net, ifr->ifr_name, ifr->ifr_ifindex);
	}

	/*
	* Perform a SIOCGIFCONF call. This structure will change
	* size eventually, and there is nothing I can do about it.
	* Thus we will need a 'compatibility mode'.
	*/
	int dev_ifconf(struct net net, struct ifconf __user uifc)
	{
	struct net_device *dev;
	void __user *pos;
	size_t size;
	int len, total = 0, done;

	/* both the ifconf and the ifreq structures are slightly different */
	if (in_compat_syscall()) {
	struct compat_ifconf ifc32;

	if (copy_from_user(&ifc32, uifc, sizeof(struct compat_ifconf)))
	return -EFAULT;

	pos = compat_ptr(ifc32.ifcbuf);
	len = ifc32.ifc_len;
	size = sizeof(struct compat_ifreq);
	} else {
	struct ifconf ifc;

	if (copy_from_user(&ifc, uifc, sizeof(struct ifconf)))
	return -EFAULT;

	pos = ifc.ifc_buf;
	len = ifc.ifc_len;
	size = sizeof(struct ifreq);
	}

	/* Loop over the interfaces, and write an info block for each. */
	rtnl_lock();
	for_each_netdev(net, dev) {
	if (!pos)
	done = inet_gifconf(dev, NULL, 0, size);
	else
	done = inet_gifconf(dev, pos + total,
	len - total, size);
	if (done < 0) {
	rtnl_unlock();
	return -EFAULT;
	}
	total += done;
	}
	rtnl_unlock();

	return put_user(total, &uifc->ifc_len);
	}

	static int dev_getifmap(struct net_device dev, struct ifreq ifr)
	{
	struct ifmap *ifmap = &ifr->ifr_map;

	if (in_compat_syscall()) {
	struct compat_ifmap cifmap = (struct compat_ifmap )ifmap;

	cifmap->mem_start = dev->mem_start;
	cifmap->mem_end = dev->mem_end;
	cifmap->base_addr = dev->base_addr;
	cifmap->irq = dev->irq;
	cifmap->dma = dev->dma;
	cifmap->port = dev->if_port;

	return 0;
	}

	ifmap->mem_start = dev->mem_start;
	ifmap->mem_end = dev->mem_end;
	ifmap->base_addr = dev->base_addr;
	ifmap->irq = dev->irq;
	ifmap->dma = dev->dma;
	ifmap->port = dev->if_port;

	return 0;
	}

	static int dev_setifmap(struct net_device dev, struct ifreq ifr)
	{
	struct compat_ifmap cifmap = (struct compat_ifmap )&ifr->ifr_map;

	if (!dev->netdev_ops->ndo_set_config)
	return -EOPNOTSUPP;

	if (in_compat_syscall()) {
	struct ifmap ifmap = {
	.mem_start = cifmap->mem_start,
	.mem_end = cifmap->mem_end,
	.base_addr = cifmap->base_addr,
	.irq = cifmap->irq,
	.dma = cifmap->dma,
	.port = cifmap->port,
	};

	return dev->netdev_ops->ndo_set_config(dev, &ifmap);
	}

	return dev->netdev_ops->ndo_set_config(dev, &ifr->ifr_map);
	}

	/*
	* Perform the SIOCxIFxxx calls, inside rcu_read_lock()
	*/
	static int dev_ifsioc_locked(struct net net, struct ifreq ifr, unsigned int cmd)
	{
	int err;
	struct net_device *dev = dev_get_by_name_rcu(net, ifr->ifr_name);

	if (!dev)
	return -ENODEV;

	switch (cmd) {
	case SIOCGIFFLAGS: /* Get interface flags */
	ifr->ifr_flags = (short) dev_get_flags(dev);
	return 0;

	case SIOCGIFMETRIC: /* Get the metric on the interface
	(currently unused) */
	ifr->ifr_metric = 0;
	return 0;

	case SIOCGIFMTU: /* Get the MTU of a device */
	ifr->ifr_mtu = dev->mtu;
	return 0;

	case SIOCGIFSLAVE:
	err = -EINVAL;
	break;

	case SIOCGIFMAP:
	return dev_getifmap(dev, ifr);

	case SIOCGIFINDEX:
	ifr->ifr_ifindex = dev->ifindex;
	return 0;

	case SIOCGIFTXQLEN:
	ifr->ifr_qlen = dev->tx_queue_len;
	return 0;

	default:
	/* dev_ioctl() should ensure this case
	* is never reached
	*/
	WARN_ON(1);
	err = -ENOTTY;
	break;

	}
	return err;
	}

	static int net_hwtstamp_validate(struct ifreq *ifr)
	{
	struct hwtstamp_config cfg;
	enum hwtstamp_tx_types tx_type;
	enum hwtstamp_rx_filters rx_filter;
	int tx_type_valid = 0;
	int rx_filter_valid = 0;

	if (copy_from_user(&cfg, ifr->ifr_data, sizeof(cfg)))
	return -EFAULT;

	if (cfg.flags) /* reserved for future extensions */
	return -EINVAL;

	tx_type = cfg.tx_type;
	rx_filter = cfg.rx_filter;

	switch (tx_type) {
	case HWTSTAMP_TX_OFF:
	case HWTSTAMP_TX_ON:
	case HWTSTAMP_TX_ONESTEP_SYNC:
	case HWTSTAMP_TX_ONESTEP_P2P:
	tx_type_valid = 1;
	break;
	case __HWTSTAMP_TX_CNT:
	/* not a real value */
	break;
	}

	switch (rx_filter) {
	case HWTSTAMP_FILTER_NONE:
	case HWTSTAMP_FILTER_ALL:
	case HWTSTAMP_FILTER_SOME:
	case HWTSTAMP_FILTER_PTP_V1_L4_EVENT:
	case HWTSTAMP_FILTER_PTP_V1_L4_SYNC:
	case HWTSTAMP_FILTER_PTP_V1_L4_DELAY_REQ:
	case HWTSTAMP_FILTER_PTP_V2_L4_EVENT:
	case HWTSTAMP_FILTER_PTP_V2_L4_SYNC:
	case HWTSTAMP_FILTER_PTP_V2_L4_DELAY_REQ:
	case HWTSTAMP_FILTER_PTP_V2_L2_EVENT:
	case HWTSTAMP_FILTER_PTP_V2_L2_SYNC:
	case HWTSTAMP_FILTER_PTP_V2_L2_DELAY_REQ:
	case HWTSTAMP_FILTER_PTP_V2_EVENT:
	case HWTSTAMP_FILTER_PTP_V2_SYNC:
	case HWTSTAMP_FILTER_PTP_V2_DELAY_REQ:
	case HWTSTAMP_FILTER_NTP_ALL:
	rx_filter_valid = 1;
	break;
	case __HWTSTAMP_FILTER_CNT:
	/* not a real value */
	break;
	}

	if (!tx_type_valid \|\| !rx_filter_valid)
	return -ERANGE;

	return 0;
	}

	static int dev_eth_ioctl(struct net_device *dev,
	struct ifreq *ifr, unsigned int cmd)
	{
	const struct net_device_ops *ops = dev->netdev_ops;
	int err;

	err = dsa_ndo_eth_ioctl(dev, ifr, cmd);
	if (err == 0 \|\| err != -EOPNOTSUPP)
	return err;

	if (ops->ndo_eth_ioctl) {
	if (netif_device_present(dev))
	err = ops->ndo_eth_ioctl(dev, ifr, cmd);
	else
	err = -ENODEV;
	}

	return err;
	}

	static int dev_siocbond(struct net_device *dev,
	struct ifreq *ifr, unsigned int cmd)
	{
	const struct net_device_ops *ops = dev->netdev_ops;

	if (ops->ndo_siocbond) {
	if (netif_device_present(dev))
	return ops->ndo_siocbond(dev, ifr, cmd);
	else
	return -ENODEV;
	}

	return -EOPNOTSUPP;
	}

	static int dev_siocdevprivate(struct net_device dev, struct ifreq ifr,
	void __user *data, unsigned int cmd)
	{
	const struct net_device_ops *ops = dev->netdev_ops;

	if (ops->ndo_siocdevprivate) {
	if (netif_device_present(dev))
	return ops->ndo_siocdevprivate(dev, ifr, data, cmd);
	else
	return -ENODEV;
	}

	return -EOPNOTSUPP;
	}

	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) {
	if (netif_device_present(dev))
	return ops->ndo_siocwandev(dev, ifs);
	else
	return -ENODEV;
	}

	return -EOPNOTSUPP;
	}

	/*
	* Perform the SIOCxIFxxx calls, inside rtnl_lock()
	*/
	static int dev_ifsioc(struct net net, struct ifreq ifr, void __user *data,
	unsigned int cmd)
	{
	int err;
	struct net_device *dev = __dev_get_by_name(net, ifr->ifr_name);
	const struct net_device_ops *ops;

	if (!dev)
	return -ENODEV;

	ops = dev->netdev_ops;

	switch (cmd) {
	case SIOCSIFFLAGS: /* Set interface flags */
	return dev_change_flags(dev, ifr->ifr_flags, NULL);

	case SIOCSIFMETRIC: /* Set the metric on the interface
	(currently unused) */
	return -EOPNOTSUPP;

	case SIOCSIFMTU: /* Set the MTU of a device */
	return dev_set_mtu(dev, ifr->ifr_mtu);

	case SIOCSIFHWADDR:
	if (dev->addr_len > sizeof(struct sockaddr))
	return -EINVAL;
	return dev_set_mac_address_user(dev, &ifr->ifr_hwaddr, NULL);

	case SIOCSIFHWBROADCAST:
	if (ifr->ifr_hwaddr.sa_family != dev->type)
	return -EINVAL;
	memcpy(dev->broadcast, ifr->ifr_hwaddr.sa_data,
	min(sizeof(ifr->ifr_hwaddr.sa_data),
	(size_t)dev->addr_len));
	call_netdevice_notifiers(NETDEV_CHANGEADDR, dev);
	return 0;

	case SIOCSIFMAP:
	return dev_setifmap(dev, ifr);

	case SIOCADDMULTI:
	if (!ops->ndo_set_rx_mode \|\|
	ifr->ifr_hwaddr.sa_family != AF_UNSPEC)
	return -EINVAL;
	if (!netif_device_present(dev))
	return -ENODEV;
	return dev_mc_add_global(dev, ifr->ifr_hwaddr.sa_data);

	case SIOCDELMULTI:
	if (!ops->ndo_set_rx_mode \|\|
	ifr->ifr_hwaddr.sa_family != AF_UNSPEC)
	return -EINVAL;
	if (!netif_device_present(dev))
	return -ENODEV;
	return dev_mc_del_global(dev, ifr->ifr_hwaddr.sa_data);

	case SIOCSIFTXQLEN:
	if (ifr->ifr_qlen < 0)
	return -EINVAL;
	return dev_change_tx_queue_len(dev, ifr->ifr_qlen);

	case SIOCSIFNAME:
	ifr->ifr_newname[IFNAMSIZ-1] = '\0';
	return dev_change_name(dev, ifr->ifr_newname);

	case SIOCWANDEV:
	return dev_siocwandev(dev, &ifr->ifr_settings);

	case SIOCBRADDIF:
	case SIOCBRDELIF:
	if (!netif_device_present(dev))
	return -ENODEV;
	if (!netif_is_bridge_master(dev))
	return -EOPNOTSUPP;
	dev_hold(dev);
	rtnl_unlock();
	err = br_ioctl_call(net, netdev_priv(dev), cmd, ifr, NULL);
	dev_put(dev);
	rtnl_lock();
	return err;

	case SIOCSHWTSTAMP:
	err = net_hwtstamp_validate(ifr);
	if (err)
	return err;
	fallthrough;

	/*
	* Unknown or private ioctl
	*/
	default:
	if (cmd >= SIOCDEVPRIVATE &&
	cmd <= SIOCDEVPRIVATE + 15)
	return dev_siocdevprivate(dev, ifr, data, cmd);

	if (cmd == SIOCGMIIPHY \|\|
	cmd == SIOCGMIIREG \|\|
	cmd == SIOCSMIIREG \|\|
	cmd == SIOCSHWTSTAMP \|\|
	cmd == SIOCGHWTSTAMP) {
	err = dev_eth_ioctl(dev, ifr, cmd);
	} else if (cmd == SIOCBONDENSLAVE \|\|
	cmd == SIOCBONDRELEASE \|\|
	cmd == SIOCBONDSETHWADDR \|\|
	cmd == SIOCBONDSLAVEINFOQUERY \|\|
	cmd == SIOCBONDINFOQUERY \|\|
	cmd == SIOCBONDCHANGEACTIVE) {
	err = dev_siocbond(dev, ifr, cmd);
	} else
	err = -EINVAL;

	}
	return err;
	}

	/**
	* dev_load - load a network module
	* @net: the applicable net namespace
	* @name: name of interface
	*
	* If a network interface is not present and the process has suitable
	* privileges this function loads the module. If module loading is not
	* available in this kernel then it becomes a nop.
	*/

	void dev_load(struct net net, const char name)
	{
	struct net_device *dev;
	int no_module;

	rcu_read_lock();
	dev = dev_get_by_name_rcu(net, name);
	rcu_read_unlock();

	no_module = !dev;
	if (no_module && capable(CAP_NET_ADMIN))
	no_module = request_module("netdev-%s", name);
	if (no_module && capable(CAP_SYS_MODULE))
	request_module("%s", name);
	}
	EXPORT_SYMBOL(dev_load);

	/*
	* This function handles all "interface"-type I/O control requests. The actual
	* 'doing' part of this is dev_ifsioc above.
	*/

	/**
	* dev_ioctl - network device ioctl
	* @net: the applicable net namespace
	* @cmd: command to issue
	* @ifr: pointer to a struct ifreq in user space
	* @need_copyout: whether or not copy_to_user() should be called
	*
	* Issue ioctl functions to devices. This is normally called by the
	* user space syscall interfaces but can sometimes be useful for
	* other purposes. The return value is the return from the syscall if
	* positive or a negative errno code on error.
	*/

	int dev_ioctl(struct net net, unsigned int cmd, struct ifreq ifr,
	void __user data, bool need_copyout)
	{
	int ret;
	char *colon;

	if (need_copyout)
	*need_copyout = true;
	if (cmd == SIOCGIFNAME)
	return dev_ifname(net, ifr);

	ifr->ifr_name[IFNAMSIZ-1] = 0;

	colon = strchr(ifr->ifr_name, ':');
	if (colon)
	*colon = 0;

	/*
	* See which interface the caller is talking about.
	*/

	switch (cmd) {
	case SIOCGIFHWADDR:
	dev_load(net, ifr->ifr_name);
	ret = dev_get_mac_address(&ifr->ifr_hwaddr, net, ifr->ifr_name);
	if (colon)
	*colon = ':';
	return ret;
	/*
	* These ioctl calls:
	* - can be done by all.
	* - atomic and do not require locking.
	* - return a value
	*/
	case SIOCGIFFLAGS:
	case SIOCGIFMETRIC:
	case SIOCGIFMTU:
	case SIOCGIFSLAVE:
	case SIOCGIFMAP:
	case SIOCGIFINDEX:
	case SIOCGIFTXQLEN:
	dev_load(net, ifr->ifr_name);
	rcu_read_lock();
	ret = dev_ifsioc_locked(net, ifr, cmd);
	rcu_read_unlock();
	if (colon)
	*colon = ':';
	return ret;

	case SIOCETHTOOL:
	dev_load(net, ifr->ifr_name);
	rtnl_lock();
	ret = dev_ethtool(net, ifr, data);
	rtnl_unlock();
	if (colon)
	*colon = ':';
	return ret;

	/*
	* These ioctl calls:
	* - require superuser power.
	* - require strict serialization.
	* - return a value
	*/
	case SIOCGMIIPHY:
	case SIOCGMIIREG:
	case SIOCSIFNAME:
	dev_load(net, ifr->ifr_name);
	if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
	return -EPERM;
	rtnl_lock();
	ret = dev_ifsioc(net, ifr, data, cmd);
	rtnl_unlock();
	if (colon)
	*colon = ':';
	return ret;

	/*
	* These ioctl calls:
	* - require superuser power.
	* - require strict serialization.
	* - do not return a value
	*/
	case SIOCSIFMAP:
	case SIOCSIFTXQLEN:
	if (!capable(CAP_NET_ADMIN))
	return -EPERM;
	fallthrough;
	/*
	* These ioctl calls:
	* - require local superuser power.
	* - require strict serialization.
	* - do not return a value
	*/
	case SIOCSIFFLAGS:
	case SIOCSIFMETRIC:
	case SIOCSIFMTU:
	case SIOCSIFHWADDR:
	case SIOCSIFSLAVE:
	case SIOCADDMULTI:
	case SIOCDELMULTI:
	case SIOCSIFHWBROADCAST:
	case SIOCSMIIREG:
	case SIOCBONDENSLAVE:
	case SIOCBONDRELEASE:
	case SIOCBONDSETHWADDR:
	case SIOCBONDCHANGEACTIVE:
	case SIOCBRADDIF:
	case SIOCBRDELIF:
	case SIOCSHWTSTAMP:
	if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
	return -EPERM;
	fallthrough;
	case SIOCBONDSLAVEINFOQUERY:
	case SIOCBONDINFOQUERY:
	dev_load(net, ifr->ifr_name);
	rtnl_lock();
	ret = dev_ifsioc(net, ifr, data, cmd);
	rtnl_unlock();
	if (need_copyout)
	*need_copyout = false;
	return ret;

	case SIOCGIFMEM:
	/* Get the per device memory space. We can add this but
	* currently do not support it */
	case SIOCSIFMEM:
	/* Set the per device memory buffer space.
	* Not applicable in our case */
	case SIOCSIFLINK:
	return -ENOTTY;

	/*
	* Unknown or private ioctl.
	*/
	default:
	if (cmd == SIOCWANDEV \|\|
	cmd == SIOCGHWTSTAMP \|\|
	(cmd >= SIOCDEVPRIVATE &&
	cmd <= SIOCDEVPRIVATE + 15)) {
	dev_load(net, ifr->ifr_name);
	rtnl_lock();
	ret = dev_ifsioc(net, ifr, data, cmd);
	rtnl_unlock();
	return ret;
	}
	return -ENOTTY;
	}
	}