xref: /linux/net/core/dev_ioctl.c (revision 24168c5e6dfbdd5b414f048f47f75d64533296ca)
1 // SPDX-License-Identifier: GPL-2.0
2 #include <linux/kmod.h>
3 #include <linux/netdevice.h>
4 #include <linux/inetdevice.h>
5 #include <linux/etherdevice.h>
6 #include <linux/rtnetlink.h>
7 #include <linux/net_tstamp.h>
8 #include <linux/phylib_stubs.h>
9 #include <linux/wireless.h>
10 #include <linux/if_bridge.h>
11 #include <net/dsa_stubs.h>
12 #include <net/wext.h>
13 
14 #include "dev.h"
15 
16 /*
17  *	Map an interface index to its name (SIOCGIFNAME)
18  */
19 
20 /*
21  *	We need this ioctl for efficient implementation of the
22  *	if_indextoname() function required by the IPv6 API.  Without
23  *	it, we would have to search all the interfaces to find a
24  *	match.  --pb
25  */
26 
27 static int dev_ifname(struct net *net, struct ifreq *ifr)
28 {
29 	ifr->ifr_name[IFNAMSIZ-1] = 0;
30 	return netdev_get_name(net, ifr->ifr_name, ifr->ifr_ifindex);
31 }
32 
33 /*
34  *	Perform a SIOCGIFCONF call. This structure will change
35  *	size eventually, and there is nothing I can do about it.
36  *	Thus we will need a 'compatibility mode'.
37  */
38 int dev_ifconf(struct net *net, struct ifconf __user *uifc)
39 {
40 	struct net_device *dev;
41 	void __user *pos;
42 	size_t size;
43 	int len, total = 0, done;
44 
45 	/* both the ifconf and the ifreq structures are slightly different */
46 	if (in_compat_syscall()) {
47 		struct compat_ifconf ifc32;
48 
49 		if (copy_from_user(&ifc32, uifc, sizeof(struct compat_ifconf)))
50 			return -EFAULT;
51 
52 		pos = compat_ptr(ifc32.ifcbuf);
53 		len = ifc32.ifc_len;
54 		size = sizeof(struct compat_ifreq);
55 	} else {
56 		struct ifconf ifc;
57 
58 		if (copy_from_user(&ifc, uifc, sizeof(struct ifconf)))
59 			return -EFAULT;
60 
61 		pos = ifc.ifc_buf;
62 		len = ifc.ifc_len;
63 		size = sizeof(struct ifreq);
64 	}
65 
66 	/* Loop over the interfaces, and write an info block for each. */
67 	rtnl_lock();
68 	for_each_netdev(net, dev) {
69 		if (!pos)
70 			done = inet_gifconf(dev, NULL, 0, size);
71 		else
72 			done = inet_gifconf(dev, pos + total,
73 					    len - total, size);
74 		if (done < 0) {
75 			rtnl_unlock();
76 			return -EFAULT;
77 		}
78 		total += done;
79 	}
80 	rtnl_unlock();
81 
82 	return put_user(total, &uifc->ifc_len);
83 }
84 
85 static int dev_getifmap(struct net_device *dev, struct ifreq *ifr)
86 {
87 	struct ifmap *ifmap = &ifr->ifr_map;
88 
89 	if (in_compat_syscall()) {
90 		struct compat_ifmap *cifmap = (struct compat_ifmap *)ifmap;
91 
92 		cifmap->mem_start = dev->mem_start;
93 		cifmap->mem_end   = dev->mem_end;
94 		cifmap->base_addr = dev->base_addr;
95 		cifmap->irq       = dev->irq;
96 		cifmap->dma       = dev->dma;
97 		cifmap->port      = dev->if_port;
98 
99 		return 0;
100 	}
101 
102 	ifmap->mem_start  = dev->mem_start;
103 	ifmap->mem_end    = dev->mem_end;
104 	ifmap->base_addr  = dev->base_addr;
105 	ifmap->irq        = dev->irq;
106 	ifmap->dma        = dev->dma;
107 	ifmap->port       = dev->if_port;
108 
109 	return 0;
110 }
111 
112 static int dev_setifmap(struct net_device *dev, struct ifreq *ifr)
113 {
114 	struct compat_ifmap *cifmap = (struct compat_ifmap *)&ifr->ifr_map;
115 
116 	if (!dev->netdev_ops->ndo_set_config)
117 		return -EOPNOTSUPP;
118 
119 	if (in_compat_syscall()) {
120 		struct ifmap ifmap = {
121 			.mem_start  = cifmap->mem_start,
122 			.mem_end    = cifmap->mem_end,
123 			.base_addr  = cifmap->base_addr,
124 			.irq        = cifmap->irq,
125 			.dma        = cifmap->dma,
126 			.port       = cifmap->port,
127 		};
128 
129 		return dev->netdev_ops->ndo_set_config(dev, &ifmap);
130 	}
131 
132 	return dev->netdev_ops->ndo_set_config(dev, &ifr->ifr_map);
133 }
134 
135 /*
136  *	Perform the SIOCxIFxxx calls, inside rcu_read_lock()
137  */
138 static int dev_ifsioc_locked(struct net *net, struct ifreq *ifr, unsigned int cmd)
139 {
140 	int err;
141 	struct net_device *dev = dev_get_by_name_rcu(net, ifr->ifr_name);
142 
143 	if (!dev)
144 		return -ENODEV;
145 
146 	switch (cmd) {
147 	case SIOCGIFFLAGS:	/* Get interface flags */
148 		ifr->ifr_flags = (short) dev_get_flags(dev);
149 		return 0;
150 
151 	case SIOCGIFMETRIC:	/* Get the metric on the interface
152 				   (currently unused) */
153 		ifr->ifr_metric = 0;
154 		return 0;
155 
156 	case SIOCGIFMTU:	/* Get the MTU of a device */
157 		ifr->ifr_mtu = dev->mtu;
158 		return 0;
159 
160 	case SIOCGIFSLAVE:
161 		err = -EINVAL;
162 		break;
163 
164 	case SIOCGIFMAP:
165 		return dev_getifmap(dev, ifr);
166 
167 	case SIOCGIFINDEX:
168 		ifr->ifr_ifindex = dev->ifindex;
169 		return 0;
170 
171 	case SIOCGIFTXQLEN:
172 		ifr->ifr_qlen = dev->tx_queue_len;
173 		return 0;
174 
175 	default:
176 		/* dev_ioctl() should ensure this case
177 		 * is never reached
178 		 */
179 		WARN_ON(1);
180 		err = -ENOTTY;
181 		break;
182 
183 	}
184 	return err;
185 }
186 
187 static int net_hwtstamp_validate(const struct kernel_hwtstamp_config *cfg)
188 {
189 	enum hwtstamp_tx_types tx_type;
190 	enum hwtstamp_rx_filters rx_filter;
191 	int tx_type_valid = 0;
192 	int rx_filter_valid = 0;
193 
194 	if (cfg->flags & ~HWTSTAMP_FLAG_MASK)
195 		return -EINVAL;
196 
197 	tx_type = cfg->tx_type;
198 	rx_filter = cfg->rx_filter;
199 
200 	switch (tx_type) {
201 	case HWTSTAMP_TX_OFF:
202 	case HWTSTAMP_TX_ON:
203 	case HWTSTAMP_TX_ONESTEP_SYNC:
204 	case HWTSTAMP_TX_ONESTEP_P2P:
205 		tx_type_valid = 1;
206 		break;
207 	case __HWTSTAMP_TX_CNT:
208 		/* not a real value */
209 		break;
210 	}
211 
212 	switch (rx_filter) {
213 	case HWTSTAMP_FILTER_NONE:
214 	case HWTSTAMP_FILTER_ALL:
215 	case HWTSTAMP_FILTER_SOME:
216 	case HWTSTAMP_FILTER_PTP_V1_L4_EVENT:
217 	case HWTSTAMP_FILTER_PTP_V1_L4_SYNC:
218 	case HWTSTAMP_FILTER_PTP_V1_L4_DELAY_REQ:
219 	case HWTSTAMP_FILTER_PTP_V2_L4_EVENT:
220 	case HWTSTAMP_FILTER_PTP_V2_L4_SYNC:
221 	case HWTSTAMP_FILTER_PTP_V2_L4_DELAY_REQ:
222 	case HWTSTAMP_FILTER_PTP_V2_L2_EVENT:
223 	case HWTSTAMP_FILTER_PTP_V2_L2_SYNC:
224 	case HWTSTAMP_FILTER_PTP_V2_L2_DELAY_REQ:
225 	case HWTSTAMP_FILTER_PTP_V2_EVENT:
226 	case HWTSTAMP_FILTER_PTP_V2_SYNC:
227 	case HWTSTAMP_FILTER_PTP_V2_DELAY_REQ:
228 	case HWTSTAMP_FILTER_NTP_ALL:
229 		rx_filter_valid = 1;
230 		break;
231 	case __HWTSTAMP_FILTER_CNT:
232 		/* not a real value */
233 		break;
234 	}
235 
236 	if (!tx_type_valid || !rx_filter_valid)
237 		return -ERANGE;
238 
239 	return 0;
240 }
241 
242 static int dev_eth_ioctl(struct net_device *dev,
243 			 struct ifreq *ifr, unsigned int cmd)
244 {
245 	const struct net_device_ops *ops = dev->netdev_ops;
246 
247 	if (!ops->ndo_eth_ioctl)
248 		return -EOPNOTSUPP;
249 
250 	if (!netif_device_present(dev))
251 		return -ENODEV;
252 
253 	return ops->ndo_eth_ioctl(dev, ifr, cmd);
254 }
255 
256 /**
257  * dev_get_hwtstamp_phylib() - Get hardware timestamping settings of NIC
258  *	or of attached phylib PHY
259  * @dev: Network device
260  * @cfg: Timestamping configuration structure
261  *
262  * Helper for enforcing a common policy that phylib timestamping, if available,
263  * should take precedence in front of hardware timestamping provided by the
264  * netdev.
265  *
266  * Note: phy_mii_ioctl() only handles SIOCSHWTSTAMP (not SIOCGHWTSTAMP), and
267  * there only exists a phydev->mii_ts->hwtstamp() method. So this will return
268  * -EOPNOTSUPP for phylib for now, which is still more accurate than letting
269  * the netdev handle the GET request.
270  */
271 static int dev_get_hwtstamp_phylib(struct net_device *dev,
272 				   struct kernel_hwtstamp_config *cfg)
273 {
274 	if (phy_has_hwtstamp(dev->phydev))
275 		return phy_hwtstamp_get(dev->phydev, cfg);
276 
277 	return dev->netdev_ops->ndo_hwtstamp_get(dev, cfg);
278 }
279 
280 static int dev_get_hwtstamp(struct net_device *dev, struct ifreq *ifr)
281 {
282 	const struct net_device_ops *ops = dev->netdev_ops;
283 	struct kernel_hwtstamp_config kernel_cfg = {};
284 	struct hwtstamp_config cfg;
285 	int err;
286 
287 	if (!ops->ndo_hwtstamp_get)
288 		return dev_eth_ioctl(dev, ifr, SIOCGHWTSTAMP); /* legacy */
289 
290 	if (!netif_device_present(dev))
291 		return -ENODEV;
292 
293 	kernel_cfg.ifr = ifr;
294 	err = dev_get_hwtstamp_phylib(dev, &kernel_cfg);
295 	if (err)
296 		return err;
297 
298 	/* If the request was resolved through an unconverted driver, omit
299 	 * the copy_to_user(), since the implementation has already done that
300 	 */
301 	if (!kernel_cfg.copied_to_user) {
302 		hwtstamp_config_from_kernel(&cfg, &kernel_cfg);
303 
304 		if (copy_to_user(ifr->ifr_data, &cfg, sizeof(cfg)))
305 			return -EFAULT;
306 	}
307 
308 	return 0;
309 }
310 
311 /**
312  * dev_set_hwtstamp_phylib() - Change hardware timestamping of NIC
313  *	or of attached phylib PHY
314  * @dev: Network device
315  * @cfg: Timestamping configuration structure
316  * @extack: Netlink extended ack message structure, for error reporting
317  *
318  * Helper for enforcing a common policy that phylib timestamping, if available,
319  * should take precedence in front of hardware timestamping provided by the
320  * netdev. If the netdev driver needs to perform specific actions even for PHY
321  * timestamping to work properly (a switch port must trap the timestamped
322  * frames and not forward them), it must set IFF_SEE_ALL_HWTSTAMP_REQUESTS in
323  * dev->priv_flags.
324  */
325 int dev_set_hwtstamp_phylib(struct net_device *dev,
326 			    struct kernel_hwtstamp_config *cfg,
327 			    struct netlink_ext_ack *extack)
328 {
329 	const struct net_device_ops *ops = dev->netdev_ops;
330 	bool phy_ts = phy_has_hwtstamp(dev->phydev);
331 	struct kernel_hwtstamp_config old_cfg = {};
332 	bool changed = false;
333 	int err;
334 
335 	cfg->source = phy_ts ? HWTSTAMP_SOURCE_PHYLIB : HWTSTAMP_SOURCE_NETDEV;
336 
337 	if (phy_ts && (dev->priv_flags & IFF_SEE_ALL_HWTSTAMP_REQUESTS)) {
338 		err = ops->ndo_hwtstamp_get(dev, &old_cfg);
339 		if (err)
340 			return err;
341 	}
342 
343 	if (!phy_ts || (dev->priv_flags & IFF_SEE_ALL_HWTSTAMP_REQUESTS)) {
344 		err = ops->ndo_hwtstamp_set(dev, cfg, extack);
345 		if (err) {
346 			if (extack->_msg)
347 				netdev_err(dev, "%s\n", extack->_msg);
348 			return err;
349 		}
350 	}
351 
352 	if (phy_ts && (dev->priv_flags & IFF_SEE_ALL_HWTSTAMP_REQUESTS))
353 		changed = kernel_hwtstamp_config_changed(&old_cfg, cfg);
354 
355 	if (phy_ts) {
356 		err = phy_hwtstamp_set(dev->phydev, cfg, extack);
357 		if (err) {
358 			if (changed)
359 				ops->ndo_hwtstamp_set(dev, &old_cfg, NULL);
360 			return err;
361 		}
362 	}
363 
364 	return 0;
365 }
366 EXPORT_SYMBOL_GPL(dev_set_hwtstamp_phylib);
367 
368 static int dev_set_hwtstamp(struct net_device *dev, struct ifreq *ifr)
369 {
370 	const struct net_device_ops *ops = dev->netdev_ops;
371 	struct kernel_hwtstamp_config kernel_cfg = {};
372 	struct netlink_ext_ack extack = {};
373 	struct hwtstamp_config cfg;
374 	int err;
375 
376 	if (copy_from_user(&cfg, ifr->ifr_data, sizeof(cfg)))
377 		return -EFAULT;
378 
379 	hwtstamp_config_to_kernel(&kernel_cfg, &cfg);
380 	kernel_cfg.ifr = ifr;
381 
382 	err = net_hwtstamp_validate(&kernel_cfg);
383 	if (err)
384 		return err;
385 
386 	err = dsa_conduit_hwtstamp_validate(dev, &kernel_cfg, &extack);
387 	if (err) {
388 		if (extack._msg)
389 			netdev_err(dev, "%s\n", extack._msg);
390 		return err;
391 	}
392 
393 	if (!ops->ndo_hwtstamp_set)
394 		return dev_eth_ioctl(dev, ifr, SIOCSHWTSTAMP); /* legacy */
395 
396 	if (!netif_device_present(dev))
397 		return -ENODEV;
398 
399 	err = dev_set_hwtstamp_phylib(dev, &kernel_cfg, &extack);
400 	if (err)
401 		return err;
402 
403 	/* The driver may have modified the configuration, so copy the
404 	 * updated version of it back to user space
405 	 */
406 	if (!kernel_cfg.copied_to_user) {
407 		hwtstamp_config_from_kernel(&cfg, &kernel_cfg);
408 
409 		if (copy_to_user(ifr->ifr_data, &cfg, sizeof(cfg)))
410 			return -EFAULT;
411 	}
412 
413 	return 0;
414 }
415 
416 static int generic_hwtstamp_ioctl_lower(struct net_device *dev, int cmd,
417 					struct kernel_hwtstamp_config *kernel_cfg)
418 {
419 	struct ifreq ifrr;
420 	int err;
421 
422 	strscpy_pad(ifrr.ifr_name, dev->name, IFNAMSIZ);
423 	ifrr.ifr_ifru = kernel_cfg->ifr->ifr_ifru;
424 
425 	err = dev_eth_ioctl(dev, &ifrr, cmd);
426 	if (err)
427 		return err;
428 
429 	kernel_cfg->ifr->ifr_ifru = ifrr.ifr_ifru;
430 	kernel_cfg->copied_to_user = true;
431 
432 	return 0;
433 }
434 
435 int generic_hwtstamp_get_lower(struct net_device *dev,
436 			       struct kernel_hwtstamp_config *kernel_cfg)
437 {
438 	const struct net_device_ops *ops = dev->netdev_ops;
439 
440 	if (!netif_device_present(dev))
441 		return -ENODEV;
442 
443 	if (ops->ndo_hwtstamp_get)
444 		return dev_get_hwtstamp_phylib(dev, kernel_cfg);
445 
446 	/* Legacy path: unconverted lower driver */
447 	return generic_hwtstamp_ioctl_lower(dev, SIOCGHWTSTAMP, kernel_cfg);
448 }
449 EXPORT_SYMBOL(generic_hwtstamp_get_lower);
450 
451 int generic_hwtstamp_set_lower(struct net_device *dev,
452 			       struct kernel_hwtstamp_config *kernel_cfg,
453 			       struct netlink_ext_ack *extack)
454 {
455 	const struct net_device_ops *ops = dev->netdev_ops;
456 
457 	if (!netif_device_present(dev))
458 		return -ENODEV;
459 
460 	if (ops->ndo_hwtstamp_set)
461 		return dev_set_hwtstamp_phylib(dev, kernel_cfg, extack);
462 
463 	/* Legacy path: unconverted lower driver */
464 	return generic_hwtstamp_ioctl_lower(dev, SIOCSHWTSTAMP, kernel_cfg);
465 }
466 EXPORT_SYMBOL(generic_hwtstamp_set_lower);
467 
468 static int dev_siocbond(struct net_device *dev,
469 			struct ifreq *ifr, unsigned int cmd)
470 {
471 	const struct net_device_ops *ops = dev->netdev_ops;
472 
473 	if (ops->ndo_siocbond) {
474 		if (netif_device_present(dev))
475 			return ops->ndo_siocbond(dev, ifr, cmd);
476 		else
477 			return -ENODEV;
478 	}
479 
480 	return -EOPNOTSUPP;
481 }
482 
483 static int dev_siocdevprivate(struct net_device *dev, struct ifreq *ifr,
484 			      void __user *data, unsigned int cmd)
485 {
486 	const struct net_device_ops *ops = dev->netdev_ops;
487 
488 	if (ops->ndo_siocdevprivate) {
489 		if (netif_device_present(dev))
490 			return ops->ndo_siocdevprivate(dev, ifr, data, cmd);
491 		else
492 			return -ENODEV;
493 	}
494 
495 	return -EOPNOTSUPP;
496 }
497 
498 static int dev_siocwandev(struct net_device *dev, struct if_settings *ifs)
499 {
500 	const struct net_device_ops *ops = dev->netdev_ops;
501 
502 	if (ops->ndo_siocwandev) {
503 		if (netif_device_present(dev))
504 			return ops->ndo_siocwandev(dev, ifs);
505 		else
506 			return -ENODEV;
507 	}
508 
509 	return -EOPNOTSUPP;
510 }
511 
512 /*
513  *	Perform the SIOCxIFxxx calls, inside rtnl_lock()
514  */
515 static int dev_ifsioc(struct net *net, struct ifreq *ifr, void __user *data,
516 		      unsigned int cmd)
517 {
518 	int err;
519 	struct net_device *dev = __dev_get_by_name(net, ifr->ifr_name);
520 	const struct net_device_ops *ops;
521 	netdevice_tracker dev_tracker;
522 
523 	if (!dev)
524 		return -ENODEV;
525 
526 	ops = dev->netdev_ops;
527 
528 	switch (cmd) {
529 	case SIOCSIFFLAGS:	/* Set interface flags */
530 		return dev_change_flags(dev, ifr->ifr_flags, NULL);
531 
532 	case SIOCSIFMETRIC:	/* Set the metric on the interface
533 				   (currently unused) */
534 		return -EOPNOTSUPP;
535 
536 	case SIOCSIFMTU:	/* Set the MTU of a device */
537 		return dev_set_mtu(dev, ifr->ifr_mtu);
538 
539 	case SIOCSIFHWADDR:
540 		if (dev->addr_len > sizeof(struct sockaddr))
541 			return -EINVAL;
542 		return dev_set_mac_address_user(dev, &ifr->ifr_hwaddr, NULL);
543 
544 	case SIOCSIFHWBROADCAST:
545 		if (ifr->ifr_hwaddr.sa_family != dev->type)
546 			return -EINVAL;
547 		memcpy(dev->broadcast, ifr->ifr_hwaddr.sa_data,
548 		       min(sizeof(ifr->ifr_hwaddr.sa_data_min),
549 			   (size_t)dev->addr_len));
550 		call_netdevice_notifiers(NETDEV_CHANGEADDR, dev);
551 		return 0;
552 
553 	case SIOCSIFMAP:
554 		return dev_setifmap(dev, ifr);
555 
556 	case SIOCADDMULTI:
557 		if (!ops->ndo_set_rx_mode ||
558 		    ifr->ifr_hwaddr.sa_family != AF_UNSPEC)
559 			return -EINVAL;
560 		if (!netif_device_present(dev))
561 			return -ENODEV;
562 		return dev_mc_add_global(dev, ifr->ifr_hwaddr.sa_data);
563 
564 	case SIOCDELMULTI:
565 		if (!ops->ndo_set_rx_mode ||
566 		    ifr->ifr_hwaddr.sa_family != AF_UNSPEC)
567 			return -EINVAL;
568 		if (!netif_device_present(dev))
569 			return -ENODEV;
570 		return dev_mc_del_global(dev, ifr->ifr_hwaddr.sa_data);
571 
572 	case SIOCSIFTXQLEN:
573 		if (ifr->ifr_qlen < 0)
574 			return -EINVAL;
575 		return dev_change_tx_queue_len(dev, ifr->ifr_qlen);
576 
577 	case SIOCSIFNAME:
578 		ifr->ifr_newname[IFNAMSIZ-1] = '\0';
579 		return dev_change_name(dev, ifr->ifr_newname);
580 
581 	case SIOCWANDEV:
582 		return dev_siocwandev(dev, &ifr->ifr_settings);
583 
584 	case SIOCBRADDIF:
585 	case SIOCBRDELIF:
586 		if (!netif_device_present(dev))
587 			return -ENODEV;
588 		if (!netif_is_bridge_master(dev))
589 			return -EOPNOTSUPP;
590 		netdev_hold(dev, &dev_tracker, GFP_KERNEL);
591 		rtnl_unlock();
592 		err = br_ioctl_call(net, netdev_priv(dev), cmd, ifr, NULL);
593 		netdev_put(dev, &dev_tracker);
594 		rtnl_lock();
595 		return err;
596 
597 	case SIOCDEVPRIVATE ... SIOCDEVPRIVATE + 15:
598 		return dev_siocdevprivate(dev, ifr, data, cmd);
599 
600 	case SIOCSHWTSTAMP:
601 		return dev_set_hwtstamp(dev, ifr);
602 
603 	case SIOCGHWTSTAMP:
604 		return dev_get_hwtstamp(dev, ifr);
605 
606 	case SIOCGMIIPHY:
607 	case SIOCGMIIREG:
608 	case SIOCSMIIREG:
609 		return dev_eth_ioctl(dev, ifr, cmd);
610 
611 	case SIOCBONDENSLAVE:
612 	case SIOCBONDRELEASE:
613 	case SIOCBONDSETHWADDR:
614 	case SIOCBONDSLAVEINFOQUERY:
615 	case SIOCBONDINFOQUERY:
616 	case SIOCBONDCHANGEACTIVE:
617 		return dev_siocbond(dev, ifr, cmd);
618 
619 	/* Unknown ioctl */
620 	default:
621 		err = -EINVAL;
622 	}
623 	return err;
624 }
625 
626 /**
627  *	dev_load 	- load a network module
628  *	@net: the applicable net namespace
629  *	@name: name of interface
630  *
631  *	If a network interface is not present and the process has suitable
632  *	privileges this function loads the module. If module loading is not
633  *	available in this kernel then it becomes a nop.
634  */
635 
636 void dev_load(struct net *net, const char *name)
637 {
638 	struct net_device *dev;
639 	int no_module;
640 
641 	rcu_read_lock();
642 	dev = dev_get_by_name_rcu(net, name);
643 	rcu_read_unlock();
644 
645 	no_module = !dev;
646 	if (no_module && capable(CAP_NET_ADMIN))
647 		no_module = request_module("netdev-%s", name);
648 	if (no_module && capable(CAP_SYS_MODULE))
649 		request_module("%s", name);
650 }
651 EXPORT_SYMBOL(dev_load);
652 
653 /*
654  *	This function handles all "interface"-type I/O control requests. The actual
655  *	'doing' part of this is dev_ifsioc above.
656  */
657 
658 /**
659  *	dev_ioctl	-	network device ioctl
660  *	@net: the applicable net namespace
661  *	@cmd: command to issue
662  *	@ifr: pointer to a struct ifreq in user space
663  *	@data: data exchanged with userspace
664  *	@need_copyout: whether or not copy_to_user() should be called
665  *
666  *	Issue ioctl functions to devices. This is normally called by the
667  *	user space syscall interfaces but can sometimes be useful for
668  *	other purposes. The return value is the return from the syscall if
669  *	positive or a negative errno code on error.
670  */
671 
672 int dev_ioctl(struct net *net, unsigned int cmd, struct ifreq *ifr,
673 	      void __user *data, bool *need_copyout)
674 {
675 	int ret;
676 	char *colon;
677 
678 	if (need_copyout)
679 		*need_copyout = true;
680 	if (cmd == SIOCGIFNAME)
681 		return dev_ifname(net, ifr);
682 
683 	ifr->ifr_name[IFNAMSIZ-1] = 0;
684 
685 	colon = strchr(ifr->ifr_name, ':');
686 	if (colon)
687 		*colon = 0;
688 
689 	/*
690 	 *	See which interface the caller is talking about.
691 	 */
692 
693 	switch (cmd) {
694 	case SIOCGIFHWADDR:
695 		dev_load(net, ifr->ifr_name);
696 		ret = dev_get_mac_address(&ifr->ifr_hwaddr, net, ifr->ifr_name);
697 		if (colon)
698 			*colon = ':';
699 		return ret;
700 	/*
701 	 *	These ioctl calls:
702 	 *	- can be done by all.
703 	 *	- atomic and do not require locking.
704 	 *	- return a value
705 	 */
706 	case SIOCGIFFLAGS:
707 	case SIOCGIFMETRIC:
708 	case SIOCGIFMTU:
709 	case SIOCGIFSLAVE:
710 	case SIOCGIFMAP:
711 	case SIOCGIFINDEX:
712 	case SIOCGIFTXQLEN:
713 		dev_load(net, ifr->ifr_name);
714 		rcu_read_lock();
715 		ret = dev_ifsioc_locked(net, ifr, cmd);
716 		rcu_read_unlock();
717 		if (colon)
718 			*colon = ':';
719 		return ret;
720 
721 	case SIOCETHTOOL:
722 		dev_load(net, ifr->ifr_name);
723 		ret = dev_ethtool(net, ifr, data);
724 		if (colon)
725 			*colon = ':';
726 		return ret;
727 
728 	/*
729 	 *	These ioctl calls:
730 	 *	- require superuser power.
731 	 *	- require strict serialization.
732 	 *	- return a value
733 	 */
734 	case SIOCGMIIPHY:
735 	case SIOCGMIIREG:
736 	case SIOCSIFNAME:
737 		dev_load(net, ifr->ifr_name);
738 		if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
739 			return -EPERM;
740 		rtnl_lock();
741 		ret = dev_ifsioc(net, ifr, data, cmd);
742 		rtnl_unlock();
743 		if (colon)
744 			*colon = ':';
745 		return ret;
746 
747 	/*
748 	 *	These ioctl calls:
749 	 *	- require superuser power.
750 	 *	- require strict serialization.
751 	 *	- do not return a value
752 	 */
753 	case SIOCSIFMAP:
754 	case SIOCSIFTXQLEN:
755 		if (!capable(CAP_NET_ADMIN))
756 			return -EPERM;
757 		fallthrough;
758 	/*
759 	 *	These ioctl calls:
760 	 *	- require local superuser power.
761 	 *	- require strict serialization.
762 	 *	- do not return a value
763 	 */
764 	case SIOCSIFFLAGS:
765 	case SIOCSIFMETRIC:
766 	case SIOCSIFMTU:
767 	case SIOCSIFHWADDR:
768 	case SIOCSIFSLAVE:
769 	case SIOCADDMULTI:
770 	case SIOCDELMULTI:
771 	case SIOCSIFHWBROADCAST:
772 	case SIOCSMIIREG:
773 	case SIOCBONDENSLAVE:
774 	case SIOCBONDRELEASE:
775 	case SIOCBONDSETHWADDR:
776 	case SIOCBONDCHANGEACTIVE:
777 	case SIOCBRADDIF:
778 	case SIOCBRDELIF:
779 	case SIOCSHWTSTAMP:
780 		if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
781 			return -EPERM;
782 		fallthrough;
783 	case SIOCBONDSLAVEINFOQUERY:
784 	case SIOCBONDINFOQUERY:
785 		dev_load(net, ifr->ifr_name);
786 		rtnl_lock();
787 		ret = dev_ifsioc(net, ifr, data, cmd);
788 		rtnl_unlock();
789 		if (need_copyout)
790 			*need_copyout = false;
791 		return ret;
792 
793 	case SIOCGIFMEM:
794 		/* Get the per device memory space. We can add this but
795 		 * currently do not support it */
796 	case SIOCSIFMEM:
797 		/* Set the per device memory buffer space.
798 		 * Not applicable in our case */
799 	case SIOCSIFLINK:
800 		return -ENOTTY;
801 
802 	/*
803 	 *	Unknown or private ioctl.
804 	 */
805 	default:
806 		if (cmd == SIOCWANDEV ||
807 		    cmd == SIOCGHWTSTAMP ||
808 		    (cmd >= SIOCDEVPRIVATE &&
809 		     cmd <= SIOCDEVPRIVATE + 15)) {
810 			dev_load(net, ifr->ifr_name);
811 			rtnl_lock();
812 			ret = dev_ifsioc(net, ifr, data, cmd);
813 			rtnl_unlock();
814 			return ret;
815 		}
816 		return -ENOTTY;
817 	}
818 }
819