xref: /linux/net/ethtool/netlink.c (revision 8137a49e1567726eb10fcf55ad141ac19804ca6b)
1 // SPDX-License-Identifier: GPL-2.0-only
2 
3 #include <net/sock.h>
4 #include <linux/ethtool_netlink.h>
5 #include "netlink.h"
6 
7 static struct genl_family ethtool_genl_family;
8 
9 static bool ethnl_ok __read_mostly;
10 static u32 ethnl_bcast_seq;
11 
12 #define ETHTOOL_FLAGS_BASIC (ETHTOOL_FLAG_COMPACT_BITSETS |	\
13 			     ETHTOOL_FLAG_OMIT_REPLY)
14 #define ETHTOOL_FLAGS_STATS (ETHTOOL_FLAGS_BASIC | ETHTOOL_FLAG_STATS)
15 
16 const struct nla_policy ethnl_header_policy[] = {
17 	[ETHTOOL_A_HEADER_DEV_INDEX]	= { .type = NLA_U32 },
18 	[ETHTOOL_A_HEADER_DEV_NAME]	= { .type = NLA_NUL_STRING,
19 					    .len = ALTIFNAMSIZ - 1 },
20 	[ETHTOOL_A_HEADER_FLAGS]	= NLA_POLICY_MASK(NLA_U32,
21 							  ETHTOOL_FLAGS_BASIC),
22 };
23 
24 const struct nla_policy ethnl_header_policy_stats[] = {
25 	[ETHTOOL_A_HEADER_DEV_INDEX]	= { .type = NLA_U32 },
26 	[ETHTOOL_A_HEADER_DEV_NAME]	= { .type = NLA_NUL_STRING,
27 					    .len = ALTIFNAMSIZ - 1 },
28 	[ETHTOOL_A_HEADER_FLAGS]	= NLA_POLICY_MASK(NLA_U32,
29 							  ETHTOOL_FLAGS_STATS),
30 };
31 
32 /**
33  * ethnl_parse_header_dev_get() - parse request header
34  * @req_info:    structure to put results into
35  * @header:      nest attribute with request header
36  * @net:         request netns
37  * @extack:      netlink extack for error reporting
38  * @require_dev: fail if no device identified in header
39  *
40  * Parse request header in nested attribute @nest and puts results into
41  * the structure pointed to by @req_info. Extack from @info is used for error
42  * reporting. If req_info->dev is not null on return, reference to it has
43  * been taken. If error is returned, *req_info is null initialized and no
44  * reference is held.
45  *
46  * Return: 0 on success or negative error code
47  */
48 int ethnl_parse_header_dev_get(struct ethnl_req_info *req_info,
49 			       const struct nlattr *header, struct net *net,
50 			       struct netlink_ext_ack *extack, bool require_dev)
51 {
52 	struct nlattr *tb[ARRAY_SIZE(ethnl_header_policy)];
53 	const struct nlattr *devname_attr;
54 	struct net_device *dev = NULL;
55 	u32 flags = 0;
56 	int ret;
57 
58 	if (!header) {
59 		NL_SET_ERR_MSG(extack, "request header missing");
60 		return -EINVAL;
61 	}
62 	/* No validation here, command policy should have a nested policy set
63 	 * for the header, therefore validation should have already been done.
64 	 */
65 	ret = nla_parse_nested(tb, ARRAY_SIZE(ethnl_header_policy) - 1, header,
66 			       NULL, extack);
67 	if (ret < 0)
68 		return ret;
69 	if (tb[ETHTOOL_A_HEADER_FLAGS])
70 		flags = nla_get_u32(tb[ETHTOOL_A_HEADER_FLAGS]);
71 
72 	devname_attr = tb[ETHTOOL_A_HEADER_DEV_NAME];
73 	if (tb[ETHTOOL_A_HEADER_DEV_INDEX]) {
74 		u32 ifindex = nla_get_u32(tb[ETHTOOL_A_HEADER_DEV_INDEX]);
75 
76 		dev = dev_get_by_index(net, ifindex);
77 		if (!dev) {
78 			NL_SET_ERR_MSG_ATTR(extack,
79 					    tb[ETHTOOL_A_HEADER_DEV_INDEX],
80 					    "no device matches ifindex");
81 			return -ENODEV;
82 		}
83 		/* if both ifindex and ifname are passed, they must match */
84 		if (devname_attr &&
85 		    strncmp(dev->name, nla_data(devname_attr), IFNAMSIZ)) {
86 			dev_put(dev);
87 			NL_SET_ERR_MSG_ATTR(extack, header,
88 					    "ifindex and name do not match");
89 			return -ENODEV;
90 		}
91 	} else if (devname_attr) {
92 		dev = dev_get_by_name(net, nla_data(devname_attr));
93 		if (!dev) {
94 			NL_SET_ERR_MSG_ATTR(extack, devname_attr,
95 					    "no device matches name");
96 			return -ENODEV;
97 		}
98 	} else if (require_dev) {
99 		NL_SET_ERR_MSG_ATTR(extack, header,
100 				    "neither ifindex nor name specified");
101 		return -EINVAL;
102 	}
103 
104 	if (dev && !netif_device_present(dev)) {
105 		dev_put(dev);
106 		NL_SET_ERR_MSG(extack, "device not present");
107 		return -ENODEV;
108 	}
109 
110 	req_info->dev = dev;
111 	req_info->flags = flags;
112 	return 0;
113 }
114 
115 /**
116  * ethnl_fill_reply_header() - Put common header into a reply message
117  * @skb:      skb with the message
118  * @dev:      network device to describe in header
119  * @attrtype: attribute type to use for the nest
120  *
121  * Create a nested attribute with attributes describing given network device.
122  *
123  * Return: 0 on success, error value (-EMSGSIZE only) on error
124  */
125 int ethnl_fill_reply_header(struct sk_buff *skb, struct net_device *dev,
126 			    u16 attrtype)
127 {
128 	struct nlattr *nest;
129 
130 	if (!dev)
131 		return 0;
132 	nest = nla_nest_start(skb, attrtype);
133 	if (!nest)
134 		return -EMSGSIZE;
135 
136 	if (nla_put_u32(skb, ETHTOOL_A_HEADER_DEV_INDEX, (u32)dev->ifindex) ||
137 	    nla_put_string(skb, ETHTOOL_A_HEADER_DEV_NAME, dev->name))
138 		goto nla_put_failure;
139 	/* If more attributes are put into reply header, ethnl_header_size()
140 	 * must be updated to account for them.
141 	 */
142 
143 	nla_nest_end(skb, nest);
144 	return 0;
145 
146 nla_put_failure:
147 	nla_nest_cancel(skb, nest);
148 	return -EMSGSIZE;
149 }
150 
151 /**
152  * ethnl_reply_init() - Create skb for a reply and fill device identification
153  * @payload:      payload length (without netlink and genetlink header)
154  * @dev:          device the reply is about (may be null)
155  * @cmd:          ETHTOOL_MSG_* message type for reply
156  * @hdr_attrtype: attribute type for common header
157  * @info:         genetlink info of the received packet we respond to
158  * @ehdrp:        place to store payload pointer returned by genlmsg_new()
159  *
160  * Return: pointer to allocated skb on success, NULL on error
161  */
162 struct sk_buff *ethnl_reply_init(size_t payload, struct net_device *dev, u8 cmd,
163 				 u16 hdr_attrtype, struct genl_info *info,
164 				 void **ehdrp)
165 {
166 	struct sk_buff *skb;
167 
168 	skb = genlmsg_new(payload, GFP_KERNEL);
169 	if (!skb)
170 		goto err;
171 	*ehdrp = genlmsg_put_reply(skb, info, &ethtool_genl_family, 0, cmd);
172 	if (!*ehdrp)
173 		goto err_free;
174 
175 	if (dev) {
176 		int ret;
177 
178 		ret = ethnl_fill_reply_header(skb, dev, hdr_attrtype);
179 		if (ret < 0)
180 			goto err_free;
181 	}
182 	return skb;
183 
184 err_free:
185 	nlmsg_free(skb);
186 err:
187 	if (info)
188 		GENL_SET_ERR_MSG(info, "failed to setup reply message");
189 	return NULL;
190 }
191 
192 void *ethnl_dump_put(struct sk_buff *skb, struct netlink_callback *cb, u8 cmd)
193 {
194 	return genlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq,
195 			   &ethtool_genl_family, 0, cmd);
196 }
197 
198 void *ethnl_bcastmsg_put(struct sk_buff *skb, u8 cmd)
199 {
200 	return genlmsg_put(skb, 0, ++ethnl_bcast_seq, &ethtool_genl_family, 0,
201 			   cmd);
202 }
203 
204 int ethnl_multicast(struct sk_buff *skb, struct net_device *dev)
205 {
206 	return genlmsg_multicast_netns(&ethtool_genl_family, dev_net(dev), skb,
207 				       0, ETHNL_MCGRP_MONITOR, GFP_KERNEL);
208 }
209 
210 /* GET request helpers */
211 
212 /**
213  * struct ethnl_dump_ctx - context structure for generic dumpit() callback
214  * @ops:        request ops of currently processed message type
215  * @req_info:   parsed request header of processed request
216  * @reply_data: data needed to compose the reply
217  * @pos_hash:   saved iteration position - hashbucket
218  * @pos_idx:    saved iteration position - index
219  *
220  * These parameters are kept in struct netlink_callback as context preserved
221  * between iterations. They are initialized by ethnl_default_start() and used
222  * in ethnl_default_dumpit() and ethnl_default_done().
223  */
224 struct ethnl_dump_ctx {
225 	const struct ethnl_request_ops	*ops;
226 	struct ethnl_req_info		*req_info;
227 	struct ethnl_reply_data		*reply_data;
228 	int				pos_hash;
229 	int				pos_idx;
230 };
231 
232 static const struct ethnl_request_ops *
233 ethnl_default_requests[__ETHTOOL_MSG_USER_CNT] = {
234 	[ETHTOOL_MSG_STRSET_GET]	= &ethnl_strset_request_ops,
235 	[ETHTOOL_MSG_LINKINFO_GET]	= &ethnl_linkinfo_request_ops,
236 	[ETHTOOL_MSG_LINKMODES_GET]	= &ethnl_linkmodes_request_ops,
237 	[ETHTOOL_MSG_LINKSTATE_GET]	= &ethnl_linkstate_request_ops,
238 	[ETHTOOL_MSG_DEBUG_GET]		= &ethnl_debug_request_ops,
239 	[ETHTOOL_MSG_WOL_GET]		= &ethnl_wol_request_ops,
240 	[ETHTOOL_MSG_FEATURES_GET]	= &ethnl_features_request_ops,
241 	[ETHTOOL_MSG_PRIVFLAGS_GET]	= &ethnl_privflags_request_ops,
242 	[ETHTOOL_MSG_RINGS_GET]		= &ethnl_rings_request_ops,
243 	[ETHTOOL_MSG_CHANNELS_GET]	= &ethnl_channels_request_ops,
244 	[ETHTOOL_MSG_COALESCE_GET]	= &ethnl_coalesce_request_ops,
245 	[ETHTOOL_MSG_PAUSE_GET]		= &ethnl_pause_request_ops,
246 	[ETHTOOL_MSG_EEE_GET]		= &ethnl_eee_request_ops,
247 	[ETHTOOL_MSG_FEC_GET]		= &ethnl_fec_request_ops,
248 	[ETHTOOL_MSG_TSINFO_GET]	= &ethnl_tsinfo_request_ops,
249 	[ETHTOOL_MSG_MODULE_EEPROM_GET]	= &ethnl_module_eeprom_request_ops,
250 	[ETHTOOL_MSG_STATS_GET]		= &ethnl_stats_request_ops,
251 };
252 
253 static struct ethnl_dump_ctx *ethnl_dump_context(struct netlink_callback *cb)
254 {
255 	return (struct ethnl_dump_ctx *)cb->ctx;
256 }
257 
258 /**
259  * ethnl_default_parse() - Parse request message
260  * @req_info:    pointer to structure to put data into
261  * @tb:		 parsed attributes
262  * @net:         request netns
263  * @request_ops: struct request_ops for request type
264  * @extack:      netlink extack for error reporting
265  * @require_dev: fail if no device identified in header
266  *
267  * Parse universal request header and call request specific ->parse_request()
268  * callback (if defined) to parse the rest of the message.
269  *
270  * Return: 0 on success or negative error code
271  */
272 static int ethnl_default_parse(struct ethnl_req_info *req_info,
273 			       struct nlattr **tb, struct net *net,
274 			       const struct ethnl_request_ops *request_ops,
275 			       struct netlink_ext_ack *extack, bool require_dev)
276 {
277 	int ret;
278 
279 	ret = ethnl_parse_header_dev_get(req_info, tb[request_ops->hdr_attr],
280 					 net, extack, require_dev);
281 	if (ret < 0)
282 		return ret;
283 
284 	if (request_ops->parse_request) {
285 		ret = request_ops->parse_request(req_info, tb, extack);
286 		if (ret < 0)
287 			return ret;
288 	}
289 
290 	return 0;
291 }
292 
293 /**
294  * ethnl_init_reply_data() - Initialize reply data for GET request
295  * @reply_data: pointer to embedded struct ethnl_reply_data
296  * @ops:        instance of struct ethnl_request_ops describing the layout
297  * @dev:        network device to initialize the reply for
298  *
299  * Fills the reply data part with zeros and sets the dev member. Must be called
300  * before calling the ->fill_reply() callback (for each iteration when handling
301  * dump requests).
302  */
303 static void ethnl_init_reply_data(struct ethnl_reply_data *reply_data,
304 				  const struct ethnl_request_ops *ops,
305 				  struct net_device *dev)
306 {
307 	memset(reply_data, 0, ops->reply_data_size);
308 	reply_data->dev = dev;
309 }
310 
311 /* default ->doit() handler for GET type requests */
312 static int ethnl_default_doit(struct sk_buff *skb, struct genl_info *info)
313 {
314 	struct ethnl_reply_data *reply_data = NULL;
315 	struct ethnl_req_info *req_info = NULL;
316 	const u8 cmd = info->genlhdr->cmd;
317 	const struct ethnl_request_ops *ops;
318 	int hdr_len, reply_len;
319 	struct sk_buff *rskb;
320 	void *reply_payload;
321 	int ret;
322 
323 	ops = ethnl_default_requests[cmd];
324 	if (WARN_ONCE(!ops, "cmd %u has no ethnl_request_ops\n", cmd))
325 		return -EOPNOTSUPP;
326 	req_info = kzalloc(ops->req_info_size, GFP_KERNEL);
327 	if (!req_info)
328 		return -ENOMEM;
329 	reply_data = kmalloc(ops->reply_data_size, GFP_KERNEL);
330 	if (!reply_data) {
331 		kfree(req_info);
332 		return -ENOMEM;
333 	}
334 
335 	ret = ethnl_default_parse(req_info, info->attrs, genl_info_net(info),
336 				  ops, info->extack, !ops->allow_nodev_do);
337 	if (ret < 0)
338 		goto err_dev;
339 	ethnl_init_reply_data(reply_data, ops, req_info->dev);
340 
341 	rtnl_lock();
342 	ret = ops->prepare_data(req_info, reply_data, info);
343 	rtnl_unlock();
344 	if (ret < 0)
345 		goto err_cleanup;
346 	ret = ops->reply_size(req_info, reply_data);
347 	if (ret < 0)
348 		goto err_cleanup;
349 	reply_len = ret;
350 	ret = -ENOMEM;
351 	rskb = ethnl_reply_init(reply_len + ethnl_reply_header_size(),
352 				req_info->dev, ops->reply_cmd,
353 				ops->hdr_attr, info, &reply_payload);
354 	if (!rskb)
355 		goto err_cleanup;
356 	hdr_len = rskb->len;
357 	ret = ops->fill_reply(rskb, req_info, reply_data);
358 	if (ret < 0)
359 		goto err_msg;
360 	WARN_ONCE(rskb->len - hdr_len > reply_len,
361 		  "ethnl cmd %d: calculated reply length %d, but consumed %d\n",
362 		  cmd, reply_len, rskb->len - hdr_len);
363 	if (ops->cleanup_data)
364 		ops->cleanup_data(reply_data);
365 
366 	genlmsg_end(rskb, reply_payload);
367 	if (req_info->dev)
368 		dev_put(req_info->dev);
369 	kfree(reply_data);
370 	kfree(req_info);
371 	return genlmsg_reply(rskb, info);
372 
373 err_msg:
374 	WARN_ONCE(ret == -EMSGSIZE, "calculated message payload length (%d) not sufficient\n", reply_len);
375 	nlmsg_free(rskb);
376 err_cleanup:
377 	if (ops->cleanup_data)
378 		ops->cleanup_data(reply_data);
379 err_dev:
380 	if (req_info->dev)
381 		dev_put(req_info->dev);
382 	kfree(reply_data);
383 	kfree(req_info);
384 	return ret;
385 }
386 
387 static int ethnl_default_dump_one(struct sk_buff *skb, struct net_device *dev,
388 				  const struct ethnl_dump_ctx *ctx,
389 				  struct netlink_callback *cb)
390 {
391 	void *ehdr;
392 	int ret;
393 
394 	ehdr = genlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq,
395 			   &ethtool_genl_family, NLM_F_MULTI,
396 			   ctx->ops->reply_cmd);
397 	if (!ehdr)
398 		return -EMSGSIZE;
399 
400 	ethnl_init_reply_data(ctx->reply_data, ctx->ops, dev);
401 	rtnl_lock();
402 	ret = ctx->ops->prepare_data(ctx->req_info, ctx->reply_data, NULL);
403 	rtnl_unlock();
404 	if (ret < 0)
405 		goto out;
406 	ret = ethnl_fill_reply_header(skb, dev, ctx->ops->hdr_attr);
407 	if (ret < 0)
408 		goto out;
409 	ret = ctx->ops->fill_reply(skb, ctx->req_info, ctx->reply_data);
410 
411 out:
412 	if (ctx->ops->cleanup_data)
413 		ctx->ops->cleanup_data(ctx->reply_data);
414 	ctx->reply_data->dev = NULL;
415 	if (ret < 0)
416 		genlmsg_cancel(skb, ehdr);
417 	else
418 		genlmsg_end(skb, ehdr);
419 	return ret;
420 }
421 
422 /* Default ->dumpit() handler for GET requests. Device iteration copied from
423  * rtnl_dump_ifinfo(); we have to be more careful about device hashtable
424  * persistence as we cannot guarantee to hold RTNL lock through the whole
425  * function as rtnetnlink does.
426  */
427 static int ethnl_default_dumpit(struct sk_buff *skb,
428 				struct netlink_callback *cb)
429 {
430 	struct ethnl_dump_ctx *ctx = ethnl_dump_context(cb);
431 	struct net *net = sock_net(skb->sk);
432 	int s_idx = ctx->pos_idx;
433 	int h, idx = 0;
434 	int ret = 0;
435 
436 	rtnl_lock();
437 	for (h = ctx->pos_hash; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
438 		struct hlist_head *head;
439 		struct net_device *dev;
440 		unsigned int seq;
441 
442 		head = &net->dev_index_head[h];
443 
444 restart_chain:
445 		seq = net->dev_base_seq;
446 		cb->seq = seq;
447 		idx = 0;
448 		hlist_for_each_entry(dev, head, index_hlist) {
449 			if (idx < s_idx)
450 				goto cont;
451 			dev_hold(dev);
452 			rtnl_unlock();
453 
454 			ret = ethnl_default_dump_one(skb, dev, ctx, cb);
455 			dev_put(dev);
456 			if (ret < 0) {
457 				if (ret == -EOPNOTSUPP)
458 					goto lock_and_cont;
459 				if (likely(skb->len))
460 					ret = skb->len;
461 				goto out;
462 			}
463 lock_and_cont:
464 			rtnl_lock();
465 			if (net->dev_base_seq != seq) {
466 				s_idx = idx + 1;
467 				goto restart_chain;
468 			}
469 cont:
470 			idx++;
471 		}
472 
473 	}
474 	rtnl_unlock();
475 
476 out:
477 	ctx->pos_hash = h;
478 	ctx->pos_idx = idx;
479 	nl_dump_check_consistent(cb, nlmsg_hdr(skb));
480 
481 	return ret;
482 }
483 
484 /* generic ->start() handler for GET requests */
485 static int ethnl_default_start(struct netlink_callback *cb)
486 {
487 	const struct genl_dumpit_info *info = genl_dumpit_info(cb);
488 	struct ethnl_dump_ctx *ctx = ethnl_dump_context(cb);
489 	struct ethnl_reply_data *reply_data;
490 	const struct ethnl_request_ops *ops;
491 	struct ethnl_req_info *req_info;
492 	struct genlmsghdr *ghdr;
493 	int ret;
494 
495 	BUILD_BUG_ON(sizeof(*ctx) > sizeof(cb->ctx));
496 
497 	ghdr = nlmsg_data(cb->nlh);
498 	ops = ethnl_default_requests[ghdr->cmd];
499 	if (WARN_ONCE(!ops, "cmd %u has no ethnl_request_ops\n", ghdr->cmd))
500 		return -EOPNOTSUPP;
501 	req_info = kzalloc(ops->req_info_size, GFP_KERNEL);
502 	if (!req_info)
503 		return -ENOMEM;
504 	reply_data = kmalloc(ops->reply_data_size, GFP_KERNEL);
505 	if (!reply_data) {
506 		ret = -ENOMEM;
507 		goto free_req_info;
508 	}
509 
510 	ret = ethnl_default_parse(req_info, info->attrs, sock_net(cb->skb->sk),
511 				  ops, cb->extack, false);
512 	if (req_info->dev) {
513 		/* We ignore device specification in dump requests but as the
514 		 * same parser as for non-dump (doit) requests is used, it
515 		 * would take reference to the device if it finds one
516 		 */
517 		dev_put(req_info->dev);
518 		req_info->dev = NULL;
519 	}
520 	if (ret < 0)
521 		goto free_reply_data;
522 
523 	ctx->ops = ops;
524 	ctx->req_info = req_info;
525 	ctx->reply_data = reply_data;
526 	ctx->pos_hash = 0;
527 	ctx->pos_idx = 0;
528 
529 	return 0;
530 
531 free_reply_data:
532 	kfree(reply_data);
533 free_req_info:
534 	kfree(req_info);
535 
536 	return ret;
537 }
538 
539 /* default ->done() handler for GET requests */
540 static int ethnl_default_done(struct netlink_callback *cb)
541 {
542 	struct ethnl_dump_ctx *ctx = ethnl_dump_context(cb);
543 
544 	kfree(ctx->reply_data);
545 	kfree(ctx->req_info);
546 
547 	return 0;
548 }
549 
550 static const struct ethnl_request_ops *
551 ethnl_default_notify_ops[ETHTOOL_MSG_KERNEL_MAX + 1] = {
552 	[ETHTOOL_MSG_LINKINFO_NTF]	= &ethnl_linkinfo_request_ops,
553 	[ETHTOOL_MSG_LINKMODES_NTF]	= &ethnl_linkmodes_request_ops,
554 	[ETHTOOL_MSG_DEBUG_NTF]		= &ethnl_debug_request_ops,
555 	[ETHTOOL_MSG_WOL_NTF]		= &ethnl_wol_request_ops,
556 	[ETHTOOL_MSG_FEATURES_NTF]	= &ethnl_features_request_ops,
557 	[ETHTOOL_MSG_PRIVFLAGS_NTF]	= &ethnl_privflags_request_ops,
558 	[ETHTOOL_MSG_RINGS_NTF]		= &ethnl_rings_request_ops,
559 	[ETHTOOL_MSG_CHANNELS_NTF]	= &ethnl_channels_request_ops,
560 	[ETHTOOL_MSG_COALESCE_NTF]	= &ethnl_coalesce_request_ops,
561 	[ETHTOOL_MSG_PAUSE_NTF]		= &ethnl_pause_request_ops,
562 	[ETHTOOL_MSG_EEE_NTF]		= &ethnl_eee_request_ops,
563 	[ETHTOOL_MSG_FEC_NTF]		= &ethnl_fec_request_ops,
564 };
565 
566 /* default notification handler */
567 static void ethnl_default_notify(struct net_device *dev, unsigned int cmd,
568 				 const void *data)
569 {
570 	struct ethnl_reply_data *reply_data;
571 	const struct ethnl_request_ops *ops;
572 	struct ethnl_req_info *req_info;
573 	struct sk_buff *skb;
574 	void *reply_payload;
575 	int reply_len;
576 	int ret;
577 
578 	if (WARN_ONCE(cmd > ETHTOOL_MSG_KERNEL_MAX ||
579 		      !ethnl_default_notify_ops[cmd],
580 		      "unexpected notification type %u\n", cmd))
581 		return;
582 	ops = ethnl_default_notify_ops[cmd];
583 	req_info = kzalloc(ops->req_info_size, GFP_KERNEL);
584 	if (!req_info)
585 		return;
586 	reply_data = kmalloc(ops->reply_data_size, GFP_KERNEL);
587 	if (!reply_data) {
588 		kfree(req_info);
589 		return;
590 	}
591 
592 	req_info->dev = dev;
593 	req_info->flags |= ETHTOOL_FLAG_COMPACT_BITSETS;
594 
595 	ethnl_init_reply_data(reply_data, ops, dev);
596 	ret = ops->prepare_data(req_info, reply_data, NULL);
597 	if (ret < 0)
598 		goto err_cleanup;
599 	ret = ops->reply_size(req_info, reply_data);
600 	if (ret < 0)
601 		goto err_cleanup;
602 	reply_len = ret + ethnl_reply_header_size();
603 	ret = -ENOMEM;
604 	skb = genlmsg_new(reply_len, GFP_KERNEL);
605 	if (!skb)
606 		goto err_cleanup;
607 	reply_payload = ethnl_bcastmsg_put(skb, cmd);
608 	if (!reply_payload)
609 		goto err_skb;
610 	ret = ethnl_fill_reply_header(skb, dev, ops->hdr_attr);
611 	if (ret < 0)
612 		goto err_msg;
613 	ret = ops->fill_reply(skb, req_info, reply_data);
614 	if (ret < 0)
615 		goto err_msg;
616 	if (ops->cleanup_data)
617 		ops->cleanup_data(reply_data);
618 
619 	genlmsg_end(skb, reply_payload);
620 	kfree(reply_data);
621 	kfree(req_info);
622 	ethnl_multicast(skb, dev);
623 	return;
624 
625 err_msg:
626 	WARN_ONCE(ret == -EMSGSIZE,
627 		  "calculated message payload length (%d) not sufficient\n",
628 		  reply_len);
629 err_skb:
630 	nlmsg_free(skb);
631 err_cleanup:
632 	if (ops->cleanup_data)
633 		ops->cleanup_data(reply_data);
634 	kfree(reply_data);
635 	kfree(req_info);
636 	return;
637 }
638 
639 /* notifications */
640 
641 typedef void (*ethnl_notify_handler_t)(struct net_device *dev, unsigned int cmd,
642 				       const void *data);
643 
644 static const ethnl_notify_handler_t ethnl_notify_handlers[] = {
645 	[ETHTOOL_MSG_LINKINFO_NTF]	= ethnl_default_notify,
646 	[ETHTOOL_MSG_LINKMODES_NTF]	= ethnl_default_notify,
647 	[ETHTOOL_MSG_DEBUG_NTF]		= ethnl_default_notify,
648 	[ETHTOOL_MSG_WOL_NTF]		= ethnl_default_notify,
649 	[ETHTOOL_MSG_FEATURES_NTF]	= ethnl_default_notify,
650 	[ETHTOOL_MSG_PRIVFLAGS_NTF]	= ethnl_default_notify,
651 	[ETHTOOL_MSG_RINGS_NTF]		= ethnl_default_notify,
652 	[ETHTOOL_MSG_CHANNELS_NTF]	= ethnl_default_notify,
653 	[ETHTOOL_MSG_COALESCE_NTF]	= ethnl_default_notify,
654 	[ETHTOOL_MSG_PAUSE_NTF]		= ethnl_default_notify,
655 	[ETHTOOL_MSG_EEE_NTF]		= ethnl_default_notify,
656 	[ETHTOOL_MSG_FEC_NTF]		= ethnl_default_notify,
657 };
658 
659 void ethtool_notify(struct net_device *dev, unsigned int cmd, const void *data)
660 {
661 	if (unlikely(!ethnl_ok))
662 		return;
663 	ASSERT_RTNL();
664 
665 	if (likely(cmd < ARRAY_SIZE(ethnl_notify_handlers) &&
666 		   ethnl_notify_handlers[cmd]))
667 		ethnl_notify_handlers[cmd](dev, cmd, data);
668 	else
669 		WARN_ONCE(1, "notification %u not implemented (dev=%s)\n",
670 			  cmd, netdev_name(dev));
671 }
672 EXPORT_SYMBOL(ethtool_notify);
673 
674 static void ethnl_notify_features(struct netdev_notifier_info *info)
675 {
676 	struct net_device *dev = netdev_notifier_info_to_dev(info);
677 
678 	ethtool_notify(dev, ETHTOOL_MSG_FEATURES_NTF, NULL);
679 }
680 
681 static int ethnl_netdev_event(struct notifier_block *this, unsigned long event,
682 			      void *ptr)
683 {
684 	switch (event) {
685 	case NETDEV_FEAT_CHANGE:
686 		ethnl_notify_features(ptr);
687 		break;
688 	}
689 
690 	return NOTIFY_DONE;
691 }
692 
693 static struct notifier_block ethnl_netdev_notifier = {
694 	.notifier_call = ethnl_netdev_event,
695 };
696 
697 /* genetlink setup */
698 
699 static const struct genl_ops ethtool_genl_ops[] = {
700 	{
701 		.cmd	= ETHTOOL_MSG_STRSET_GET,
702 		.doit	= ethnl_default_doit,
703 		.start	= ethnl_default_start,
704 		.dumpit	= ethnl_default_dumpit,
705 		.done	= ethnl_default_done,
706 		.policy = ethnl_strset_get_policy,
707 		.maxattr = ARRAY_SIZE(ethnl_strset_get_policy) - 1,
708 	},
709 	{
710 		.cmd	= ETHTOOL_MSG_LINKINFO_GET,
711 		.doit	= ethnl_default_doit,
712 		.start	= ethnl_default_start,
713 		.dumpit	= ethnl_default_dumpit,
714 		.done	= ethnl_default_done,
715 		.policy = ethnl_linkinfo_get_policy,
716 		.maxattr = ARRAY_SIZE(ethnl_linkinfo_get_policy) - 1,
717 	},
718 	{
719 		.cmd	= ETHTOOL_MSG_LINKINFO_SET,
720 		.flags	= GENL_UNS_ADMIN_PERM,
721 		.doit	= ethnl_set_linkinfo,
722 		.policy = ethnl_linkinfo_set_policy,
723 		.maxattr = ARRAY_SIZE(ethnl_linkinfo_set_policy) - 1,
724 	},
725 	{
726 		.cmd	= ETHTOOL_MSG_LINKMODES_GET,
727 		.doit	= ethnl_default_doit,
728 		.start	= ethnl_default_start,
729 		.dumpit	= ethnl_default_dumpit,
730 		.done	= ethnl_default_done,
731 		.policy = ethnl_linkmodes_get_policy,
732 		.maxattr = ARRAY_SIZE(ethnl_linkmodes_get_policy) - 1,
733 	},
734 	{
735 		.cmd	= ETHTOOL_MSG_LINKMODES_SET,
736 		.flags	= GENL_UNS_ADMIN_PERM,
737 		.doit	= ethnl_set_linkmodes,
738 		.policy = ethnl_linkmodes_set_policy,
739 		.maxattr = ARRAY_SIZE(ethnl_linkmodes_set_policy) - 1,
740 	},
741 	{
742 		.cmd	= ETHTOOL_MSG_LINKSTATE_GET,
743 		.doit	= ethnl_default_doit,
744 		.start	= ethnl_default_start,
745 		.dumpit	= ethnl_default_dumpit,
746 		.done	= ethnl_default_done,
747 		.policy = ethnl_linkstate_get_policy,
748 		.maxattr = ARRAY_SIZE(ethnl_linkstate_get_policy) - 1,
749 	},
750 	{
751 		.cmd	= ETHTOOL_MSG_DEBUG_GET,
752 		.doit	= ethnl_default_doit,
753 		.start	= ethnl_default_start,
754 		.dumpit	= ethnl_default_dumpit,
755 		.done	= ethnl_default_done,
756 		.policy = ethnl_debug_get_policy,
757 		.maxattr = ARRAY_SIZE(ethnl_debug_get_policy) - 1,
758 	},
759 	{
760 		.cmd	= ETHTOOL_MSG_DEBUG_SET,
761 		.flags	= GENL_UNS_ADMIN_PERM,
762 		.doit	= ethnl_set_debug,
763 		.policy = ethnl_debug_set_policy,
764 		.maxattr = ARRAY_SIZE(ethnl_debug_set_policy) - 1,
765 	},
766 	{
767 		.cmd	= ETHTOOL_MSG_WOL_GET,
768 		.flags	= GENL_UNS_ADMIN_PERM,
769 		.doit	= ethnl_default_doit,
770 		.start	= ethnl_default_start,
771 		.dumpit	= ethnl_default_dumpit,
772 		.done	= ethnl_default_done,
773 		.policy = ethnl_wol_get_policy,
774 		.maxattr = ARRAY_SIZE(ethnl_wol_get_policy) - 1,
775 	},
776 	{
777 		.cmd	= ETHTOOL_MSG_WOL_SET,
778 		.flags	= GENL_UNS_ADMIN_PERM,
779 		.doit	= ethnl_set_wol,
780 		.policy = ethnl_wol_set_policy,
781 		.maxattr = ARRAY_SIZE(ethnl_wol_set_policy) - 1,
782 	},
783 	{
784 		.cmd	= ETHTOOL_MSG_FEATURES_GET,
785 		.doit	= ethnl_default_doit,
786 		.start	= ethnl_default_start,
787 		.dumpit	= ethnl_default_dumpit,
788 		.done	= ethnl_default_done,
789 		.policy = ethnl_features_get_policy,
790 		.maxattr = ARRAY_SIZE(ethnl_features_get_policy) - 1,
791 	},
792 	{
793 		.cmd	= ETHTOOL_MSG_FEATURES_SET,
794 		.flags	= GENL_UNS_ADMIN_PERM,
795 		.doit	= ethnl_set_features,
796 		.policy = ethnl_features_set_policy,
797 		.maxattr = ARRAY_SIZE(ethnl_features_set_policy) - 1,
798 	},
799 	{
800 		.cmd	= ETHTOOL_MSG_PRIVFLAGS_GET,
801 		.doit	= ethnl_default_doit,
802 		.start	= ethnl_default_start,
803 		.dumpit	= ethnl_default_dumpit,
804 		.done	= ethnl_default_done,
805 		.policy = ethnl_privflags_get_policy,
806 		.maxattr = ARRAY_SIZE(ethnl_privflags_get_policy) - 1,
807 	},
808 	{
809 		.cmd	= ETHTOOL_MSG_PRIVFLAGS_SET,
810 		.flags	= GENL_UNS_ADMIN_PERM,
811 		.doit	= ethnl_set_privflags,
812 		.policy = ethnl_privflags_set_policy,
813 		.maxattr = ARRAY_SIZE(ethnl_privflags_set_policy) - 1,
814 	},
815 	{
816 		.cmd	= ETHTOOL_MSG_RINGS_GET,
817 		.doit	= ethnl_default_doit,
818 		.start	= ethnl_default_start,
819 		.dumpit	= ethnl_default_dumpit,
820 		.done	= ethnl_default_done,
821 		.policy = ethnl_rings_get_policy,
822 		.maxattr = ARRAY_SIZE(ethnl_rings_get_policy) - 1,
823 	},
824 	{
825 		.cmd	= ETHTOOL_MSG_RINGS_SET,
826 		.flags	= GENL_UNS_ADMIN_PERM,
827 		.doit	= ethnl_set_rings,
828 		.policy = ethnl_rings_set_policy,
829 		.maxattr = ARRAY_SIZE(ethnl_rings_set_policy) - 1,
830 	},
831 	{
832 		.cmd	= ETHTOOL_MSG_CHANNELS_GET,
833 		.doit	= ethnl_default_doit,
834 		.start	= ethnl_default_start,
835 		.dumpit	= ethnl_default_dumpit,
836 		.done	= ethnl_default_done,
837 		.policy = ethnl_channels_get_policy,
838 		.maxattr = ARRAY_SIZE(ethnl_channels_get_policy) - 1,
839 	},
840 	{
841 		.cmd	= ETHTOOL_MSG_CHANNELS_SET,
842 		.flags	= GENL_UNS_ADMIN_PERM,
843 		.doit	= ethnl_set_channels,
844 		.policy = ethnl_channels_set_policy,
845 		.maxattr = ARRAY_SIZE(ethnl_channels_set_policy) - 1,
846 	},
847 	{
848 		.cmd	= ETHTOOL_MSG_COALESCE_GET,
849 		.doit	= ethnl_default_doit,
850 		.start	= ethnl_default_start,
851 		.dumpit	= ethnl_default_dumpit,
852 		.done	= ethnl_default_done,
853 		.policy = ethnl_coalesce_get_policy,
854 		.maxattr = ARRAY_SIZE(ethnl_coalesce_get_policy) - 1,
855 	},
856 	{
857 		.cmd	= ETHTOOL_MSG_COALESCE_SET,
858 		.flags	= GENL_UNS_ADMIN_PERM,
859 		.doit	= ethnl_set_coalesce,
860 		.policy = ethnl_coalesce_set_policy,
861 		.maxattr = ARRAY_SIZE(ethnl_coalesce_set_policy) - 1,
862 	},
863 	{
864 		.cmd	= ETHTOOL_MSG_PAUSE_GET,
865 		.doit	= ethnl_default_doit,
866 		.start	= ethnl_default_start,
867 		.dumpit	= ethnl_default_dumpit,
868 		.done	= ethnl_default_done,
869 		.policy = ethnl_pause_get_policy,
870 		.maxattr = ARRAY_SIZE(ethnl_pause_get_policy) - 1,
871 	},
872 	{
873 		.cmd	= ETHTOOL_MSG_PAUSE_SET,
874 		.flags	= GENL_UNS_ADMIN_PERM,
875 		.doit	= ethnl_set_pause,
876 		.policy = ethnl_pause_set_policy,
877 		.maxattr = ARRAY_SIZE(ethnl_pause_set_policy) - 1,
878 	},
879 	{
880 		.cmd	= ETHTOOL_MSG_EEE_GET,
881 		.doit	= ethnl_default_doit,
882 		.start	= ethnl_default_start,
883 		.dumpit	= ethnl_default_dumpit,
884 		.done	= ethnl_default_done,
885 		.policy = ethnl_eee_get_policy,
886 		.maxattr = ARRAY_SIZE(ethnl_eee_get_policy) - 1,
887 	},
888 	{
889 		.cmd	= ETHTOOL_MSG_EEE_SET,
890 		.flags	= GENL_UNS_ADMIN_PERM,
891 		.doit	= ethnl_set_eee,
892 		.policy = ethnl_eee_set_policy,
893 		.maxattr = ARRAY_SIZE(ethnl_eee_set_policy) - 1,
894 	},
895 	{
896 		.cmd	= ETHTOOL_MSG_TSINFO_GET,
897 		.doit	= ethnl_default_doit,
898 		.start	= ethnl_default_start,
899 		.dumpit	= ethnl_default_dumpit,
900 		.done	= ethnl_default_done,
901 		.policy = ethnl_tsinfo_get_policy,
902 		.maxattr = ARRAY_SIZE(ethnl_tsinfo_get_policy) - 1,
903 	},
904 	{
905 		.cmd	= ETHTOOL_MSG_CABLE_TEST_ACT,
906 		.flags	= GENL_UNS_ADMIN_PERM,
907 		.doit	= ethnl_act_cable_test,
908 		.policy = ethnl_cable_test_act_policy,
909 		.maxattr = ARRAY_SIZE(ethnl_cable_test_act_policy) - 1,
910 	},
911 	{
912 		.cmd	= ETHTOOL_MSG_CABLE_TEST_TDR_ACT,
913 		.flags	= GENL_UNS_ADMIN_PERM,
914 		.doit	= ethnl_act_cable_test_tdr,
915 		.policy = ethnl_cable_test_tdr_act_policy,
916 		.maxattr = ARRAY_SIZE(ethnl_cable_test_tdr_act_policy) - 1,
917 	},
918 	{
919 		.cmd	= ETHTOOL_MSG_TUNNEL_INFO_GET,
920 		.doit	= ethnl_tunnel_info_doit,
921 		.start	= ethnl_tunnel_info_start,
922 		.dumpit	= ethnl_tunnel_info_dumpit,
923 		.policy = ethnl_tunnel_info_get_policy,
924 		.maxattr = ARRAY_SIZE(ethnl_tunnel_info_get_policy) - 1,
925 	},
926 	{
927 		.cmd	= ETHTOOL_MSG_FEC_GET,
928 		.doit	= ethnl_default_doit,
929 		.start	= ethnl_default_start,
930 		.dumpit	= ethnl_default_dumpit,
931 		.done	= ethnl_default_done,
932 		.policy = ethnl_fec_get_policy,
933 		.maxattr = ARRAY_SIZE(ethnl_fec_get_policy) - 1,
934 	},
935 	{
936 		.cmd	= ETHTOOL_MSG_FEC_SET,
937 		.flags	= GENL_UNS_ADMIN_PERM,
938 		.doit	= ethnl_set_fec,
939 		.policy = ethnl_fec_set_policy,
940 		.maxattr = ARRAY_SIZE(ethnl_fec_set_policy) - 1,
941 	},
942 	{
943 		.cmd	= ETHTOOL_MSG_MODULE_EEPROM_GET,
944 		.flags  = GENL_UNS_ADMIN_PERM,
945 		.doit	= ethnl_default_doit,
946 		.start	= ethnl_default_start,
947 		.dumpit	= ethnl_default_dumpit,
948 		.done	= ethnl_default_done,
949 		.policy = ethnl_module_eeprom_get_policy,
950 		.maxattr = ARRAY_SIZE(ethnl_module_eeprom_get_policy) - 1,
951 	},
952 	{
953 		.cmd	= ETHTOOL_MSG_STATS_GET,
954 		.doit	= ethnl_default_doit,
955 		.start	= ethnl_default_start,
956 		.dumpit	= ethnl_default_dumpit,
957 		.done	= ethnl_default_done,
958 		.policy = ethnl_stats_get_policy,
959 		.maxattr = ARRAY_SIZE(ethnl_stats_get_policy) - 1,
960 	},
961 };
962 
963 static const struct genl_multicast_group ethtool_nl_mcgrps[] = {
964 	[ETHNL_MCGRP_MONITOR] = { .name = ETHTOOL_MCGRP_MONITOR_NAME },
965 };
966 
967 static struct genl_family ethtool_genl_family __ro_after_init = {
968 	.name		= ETHTOOL_GENL_NAME,
969 	.version	= ETHTOOL_GENL_VERSION,
970 	.netnsok	= true,
971 	.parallel_ops	= true,
972 	.ops		= ethtool_genl_ops,
973 	.n_ops		= ARRAY_SIZE(ethtool_genl_ops),
974 	.mcgrps		= ethtool_nl_mcgrps,
975 	.n_mcgrps	= ARRAY_SIZE(ethtool_nl_mcgrps),
976 };
977 
978 /* module setup */
979 
980 static int __init ethnl_init(void)
981 {
982 	int ret;
983 
984 	ret = genl_register_family(&ethtool_genl_family);
985 	if (WARN(ret < 0, "ethtool: genetlink family registration failed"))
986 		return ret;
987 	ethnl_ok = true;
988 
989 	ret = register_netdevice_notifier(&ethnl_netdev_notifier);
990 	WARN(ret < 0, "ethtool: net device notifier registration failed");
991 	return ret;
992 }
993 
994 subsys_initcall(ethnl_init);
995