xref: /openbmc/linux/net/ethtool/netlink.c (revision 132db935)
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 static const struct nla_policy ethnl_header_policy[ETHTOOL_A_HEADER_MAX + 1] = {
13 	[ETHTOOL_A_HEADER_UNSPEC]	= { .type = NLA_REJECT },
14 	[ETHTOOL_A_HEADER_DEV_INDEX]	= { .type = NLA_U32 },
15 	[ETHTOOL_A_HEADER_DEV_NAME]	= { .type = NLA_NUL_STRING,
16 					    .len = ALTIFNAMSIZ - 1 },
17 	[ETHTOOL_A_HEADER_FLAGS]	= { .type = NLA_U32 },
18 };
19 
20 /**
21  * ethnl_parse_header_dev_get() - parse request header
22  * @req_info:    structure to put results into
23  * @header:      nest attribute with request header
24  * @net:         request netns
25  * @extack:      netlink extack for error reporting
26  * @require_dev: fail if no device identified in header
27  *
28  * Parse request header in nested attribute @nest and puts results into
29  * the structure pointed to by @req_info. Extack from @info is used for error
30  * reporting. If req_info->dev is not null on return, reference to it has
31  * been taken. If error is returned, *req_info is null initialized and no
32  * reference is held.
33  *
34  * Return: 0 on success or negative error code
35  */
36 int ethnl_parse_header_dev_get(struct ethnl_req_info *req_info,
37 			       const struct nlattr *header, struct net *net,
38 			       struct netlink_ext_ack *extack, bool require_dev)
39 {
40 	struct nlattr *tb[ETHTOOL_A_HEADER_MAX + 1];
41 	const struct nlattr *devname_attr;
42 	struct net_device *dev = NULL;
43 	u32 flags = 0;
44 	int ret;
45 
46 	if (!header) {
47 		NL_SET_ERR_MSG(extack, "request header missing");
48 		return -EINVAL;
49 	}
50 	ret = nla_parse_nested(tb, ETHTOOL_A_HEADER_MAX, header,
51 			       ethnl_header_policy, extack);
52 	if (ret < 0)
53 		return ret;
54 	if (tb[ETHTOOL_A_HEADER_FLAGS]) {
55 		flags = nla_get_u32(tb[ETHTOOL_A_HEADER_FLAGS]);
56 		if (flags & ~ETHTOOL_FLAG_ALL) {
57 			NL_SET_ERR_MSG_ATTR(extack, tb[ETHTOOL_A_HEADER_FLAGS],
58 					    "unrecognized request flags");
59 			nl_set_extack_cookie_u32(extack, ETHTOOL_FLAG_ALL);
60 			return -EOPNOTSUPP;
61 		}
62 	}
63 
64 	devname_attr = tb[ETHTOOL_A_HEADER_DEV_NAME];
65 	if (tb[ETHTOOL_A_HEADER_DEV_INDEX]) {
66 		u32 ifindex = nla_get_u32(tb[ETHTOOL_A_HEADER_DEV_INDEX]);
67 
68 		dev = dev_get_by_index(net, ifindex);
69 		if (!dev) {
70 			NL_SET_ERR_MSG_ATTR(extack,
71 					    tb[ETHTOOL_A_HEADER_DEV_INDEX],
72 					    "no device matches ifindex");
73 			return -ENODEV;
74 		}
75 		/* if both ifindex and ifname are passed, they must match */
76 		if (devname_attr &&
77 		    strncmp(dev->name, nla_data(devname_attr), IFNAMSIZ)) {
78 			dev_put(dev);
79 			NL_SET_ERR_MSG_ATTR(extack, header,
80 					    "ifindex and name do not match");
81 			return -ENODEV;
82 		}
83 	} else if (devname_attr) {
84 		dev = dev_get_by_name(net, nla_data(devname_attr));
85 		if (!dev) {
86 			NL_SET_ERR_MSG_ATTR(extack, devname_attr,
87 					    "no device matches name");
88 			return -ENODEV;
89 		}
90 	} else if (require_dev) {
91 		NL_SET_ERR_MSG_ATTR(extack, header,
92 				    "neither ifindex nor name specified");
93 		return -EINVAL;
94 	}
95 
96 	if (dev && !netif_device_present(dev)) {
97 		dev_put(dev);
98 		NL_SET_ERR_MSG(extack, "device not present");
99 		return -ENODEV;
100 	}
101 
102 	req_info->dev = dev;
103 	req_info->flags = flags;
104 	return 0;
105 }
106 
107 /**
108  * ethnl_fill_reply_header() - Put common header into a reply message
109  * @skb:      skb with the message
110  * @dev:      network device to describe in header
111  * @attrtype: attribute type to use for the nest
112  *
113  * Create a nested attribute with attributes describing given network device.
114  *
115  * Return: 0 on success, error value (-EMSGSIZE only) on error
116  */
117 int ethnl_fill_reply_header(struct sk_buff *skb, struct net_device *dev,
118 			    u16 attrtype)
119 {
120 	struct nlattr *nest;
121 
122 	if (!dev)
123 		return 0;
124 	nest = nla_nest_start(skb, attrtype);
125 	if (!nest)
126 		return -EMSGSIZE;
127 
128 	if (nla_put_u32(skb, ETHTOOL_A_HEADER_DEV_INDEX, (u32)dev->ifindex) ||
129 	    nla_put_string(skb, ETHTOOL_A_HEADER_DEV_NAME, dev->name))
130 		goto nla_put_failure;
131 	/* If more attributes are put into reply header, ethnl_header_size()
132 	 * must be updated to account for them.
133 	 */
134 
135 	nla_nest_end(skb, nest);
136 	return 0;
137 
138 nla_put_failure:
139 	nla_nest_cancel(skb, nest);
140 	return -EMSGSIZE;
141 }
142 
143 /**
144  * ethnl_reply_init() - Create skb for a reply and fill device identification
145  * @payload:      payload length (without netlink and genetlink header)
146  * @dev:          device the reply is about (may be null)
147  * @cmd:          ETHTOOL_MSG_* message type for reply
148  * @hdr_attrtype: attribute type for common header
149  * @info:         genetlink info of the received packet we respond to
150  * @ehdrp:        place to store payload pointer returned by genlmsg_new()
151  *
152  * Return: pointer to allocated skb on success, NULL on error
153  */
154 struct sk_buff *ethnl_reply_init(size_t payload, struct net_device *dev, u8 cmd,
155 				 u16 hdr_attrtype, struct genl_info *info,
156 				 void **ehdrp)
157 {
158 	struct sk_buff *skb;
159 
160 	skb = genlmsg_new(payload, GFP_KERNEL);
161 	if (!skb)
162 		goto err;
163 	*ehdrp = genlmsg_put_reply(skb, info, &ethtool_genl_family, 0, cmd);
164 	if (!*ehdrp)
165 		goto err_free;
166 
167 	if (dev) {
168 		int ret;
169 
170 		ret = ethnl_fill_reply_header(skb, dev, hdr_attrtype);
171 		if (ret < 0)
172 			goto err_free;
173 	}
174 	return skb;
175 
176 err_free:
177 	nlmsg_free(skb);
178 err:
179 	if (info)
180 		GENL_SET_ERR_MSG(info, "failed to setup reply message");
181 	return NULL;
182 }
183 
184 void *ethnl_bcastmsg_put(struct sk_buff *skb, u8 cmd)
185 {
186 	return genlmsg_put(skb, 0, ++ethnl_bcast_seq, &ethtool_genl_family, 0,
187 			   cmd);
188 }
189 
190 int ethnl_multicast(struct sk_buff *skb, struct net_device *dev)
191 {
192 	return genlmsg_multicast_netns(&ethtool_genl_family, dev_net(dev), skb,
193 				       0, ETHNL_MCGRP_MONITOR, GFP_KERNEL);
194 }
195 
196 /* GET request helpers */
197 
198 /**
199  * struct ethnl_dump_ctx - context structure for generic dumpit() callback
200  * @ops:        request ops of currently processed message type
201  * @req_info:   parsed request header of processed request
202  * @reply_data: data needed to compose the reply
203  * @pos_hash:   saved iteration position - hashbucket
204  * @pos_idx:    saved iteration position - index
205  *
206  * These parameters are kept in struct netlink_callback as context preserved
207  * between iterations. They are initialized by ethnl_default_start() and used
208  * in ethnl_default_dumpit() and ethnl_default_done().
209  */
210 struct ethnl_dump_ctx {
211 	const struct ethnl_request_ops	*ops;
212 	struct ethnl_req_info		*req_info;
213 	struct ethnl_reply_data		*reply_data;
214 	int				pos_hash;
215 	int				pos_idx;
216 };
217 
218 static const struct ethnl_request_ops *
219 ethnl_default_requests[__ETHTOOL_MSG_USER_CNT] = {
220 	[ETHTOOL_MSG_STRSET_GET]	= &ethnl_strset_request_ops,
221 	[ETHTOOL_MSG_LINKINFO_GET]	= &ethnl_linkinfo_request_ops,
222 	[ETHTOOL_MSG_LINKMODES_GET]	= &ethnl_linkmodes_request_ops,
223 	[ETHTOOL_MSG_LINKSTATE_GET]	= &ethnl_linkstate_request_ops,
224 	[ETHTOOL_MSG_DEBUG_GET]		= &ethnl_debug_request_ops,
225 	[ETHTOOL_MSG_WOL_GET]		= &ethnl_wol_request_ops,
226 	[ETHTOOL_MSG_FEATURES_GET]	= &ethnl_features_request_ops,
227 	[ETHTOOL_MSG_PRIVFLAGS_GET]	= &ethnl_privflags_request_ops,
228 	[ETHTOOL_MSG_RINGS_GET]		= &ethnl_rings_request_ops,
229 	[ETHTOOL_MSG_CHANNELS_GET]	= &ethnl_channels_request_ops,
230 	[ETHTOOL_MSG_COALESCE_GET]	= &ethnl_coalesce_request_ops,
231 	[ETHTOOL_MSG_PAUSE_GET]		= &ethnl_pause_request_ops,
232 	[ETHTOOL_MSG_EEE_GET]		= &ethnl_eee_request_ops,
233 	[ETHTOOL_MSG_TSINFO_GET]	= &ethnl_tsinfo_request_ops,
234 };
235 
236 static struct ethnl_dump_ctx *ethnl_dump_context(struct netlink_callback *cb)
237 {
238 	return (struct ethnl_dump_ctx *)cb->ctx;
239 }
240 
241 /**
242  * ethnl_default_parse() - Parse request message
243  * @req_info:    pointer to structure to put data into
244  * @nlhdr:       pointer to request message header
245  * @net:         request netns
246  * @request_ops: struct request_ops for request type
247  * @extack:      netlink extack for error reporting
248  * @require_dev: fail if no device identified in header
249  *
250  * Parse universal request header and call request specific ->parse_request()
251  * callback (if defined) to parse the rest of the message.
252  *
253  * Return: 0 on success or negative error code
254  */
255 static int ethnl_default_parse(struct ethnl_req_info *req_info,
256 			       const struct nlmsghdr *nlhdr, struct net *net,
257 			       const struct ethnl_request_ops *request_ops,
258 			       struct netlink_ext_ack *extack, bool require_dev)
259 {
260 	struct nlattr **tb;
261 	int ret;
262 
263 	tb = kmalloc_array(request_ops->max_attr + 1, sizeof(tb[0]),
264 			   GFP_KERNEL);
265 	if (!tb)
266 		return -ENOMEM;
267 
268 	ret = nlmsg_parse(nlhdr, GENL_HDRLEN, tb, request_ops->max_attr,
269 			  request_ops->request_policy, extack);
270 	if (ret < 0)
271 		goto out;
272 	ret = ethnl_parse_header_dev_get(req_info, tb[request_ops->hdr_attr],
273 					 net, extack, require_dev);
274 	if (ret < 0)
275 		goto out;
276 
277 	if (request_ops->parse_request) {
278 		ret = request_ops->parse_request(req_info, tb, extack);
279 		if (ret < 0)
280 			goto out;
281 	}
282 
283 	ret = 0;
284 out:
285 	kfree(tb);
286 	return ret;
287 }
288 
289 /**
290  * ethnl_init_reply_data() - Initialize reply data for GET request
291  * @reply_data: pointer to embedded struct ethnl_reply_data
292  * @ops:        instance of struct ethnl_request_ops describing the layout
293  * @dev:        network device to initialize the reply for
294  *
295  * Fills the reply data part with zeros and sets the dev member. Must be called
296  * before calling the ->fill_reply() callback (for each iteration when handling
297  * dump requests).
298  */
299 static void ethnl_init_reply_data(struct ethnl_reply_data *reply_data,
300 				  const struct ethnl_request_ops *ops,
301 				  struct net_device *dev)
302 {
303 	memset(reply_data, 0, ops->reply_data_size);
304 	reply_data->dev = dev;
305 }
306 
307 /* default ->doit() handler for GET type requests */
308 static int ethnl_default_doit(struct sk_buff *skb, struct genl_info *info)
309 {
310 	struct ethnl_reply_data *reply_data = NULL;
311 	struct ethnl_req_info *req_info = NULL;
312 	const u8 cmd = info->genlhdr->cmd;
313 	const struct ethnl_request_ops *ops;
314 	struct sk_buff *rskb;
315 	void *reply_payload;
316 	int reply_len;
317 	int ret;
318 
319 	ops = ethnl_default_requests[cmd];
320 	if (WARN_ONCE(!ops, "cmd %u has no ethnl_request_ops\n", cmd))
321 		return -EOPNOTSUPP;
322 	req_info = kzalloc(ops->req_info_size, GFP_KERNEL);
323 	if (!req_info)
324 		return -ENOMEM;
325 	reply_data = kmalloc(ops->reply_data_size, GFP_KERNEL);
326 	if (!reply_data) {
327 		kfree(req_info);
328 		return -ENOMEM;
329 	}
330 
331 	ret = ethnl_default_parse(req_info, info->nlhdr, genl_info_net(info), ops,
332 				  info->extack, !ops->allow_nodev_do);
333 	if (ret < 0)
334 		goto err_dev;
335 	ethnl_init_reply_data(reply_data, ops, req_info->dev);
336 
337 	rtnl_lock();
338 	ret = ops->prepare_data(req_info, reply_data, info);
339 	rtnl_unlock();
340 	if (ret < 0)
341 		goto err_cleanup;
342 	ret = ops->reply_size(req_info, reply_data);
343 	if (ret < 0)
344 		goto err_cleanup;
345 	reply_len = ret + ethnl_reply_header_size();
346 	ret = -ENOMEM;
347 	rskb = ethnl_reply_init(reply_len, req_info->dev, ops->reply_cmd,
348 				ops->hdr_attr, info, &reply_payload);
349 	if (!rskb)
350 		goto err_cleanup;
351 	ret = ops->fill_reply(rskb, req_info, reply_data);
352 	if (ret < 0)
353 		goto err_msg;
354 	if (ops->cleanup_data)
355 		ops->cleanup_data(reply_data);
356 
357 	genlmsg_end(rskb, reply_payload);
358 	if (req_info->dev)
359 		dev_put(req_info->dev);
360 	kfree(reply_data);
361 	kfree(req_info);
362 	return genlmsg_reply(rskb, info);
363 
364 err_msg:
365 	WARN_ONCE(ret == -EMSGSIZE, "calculated message payload length (%d) not sufficient\n", reply_len);
366 	nlmsg_free(rskb);
367 err_cleanup:
368 	if (ops->cleanup_data)
369 		ops->cleanup_data(reply_data);
370 err_dev:
371 	if (req_info->dev)
372 		dev_put(req_info->dev);
373 	kfree(reply_data);
374 	kfree(req_info);
375 	return ret;
376 }
377 
378 static int ethnl_default_dump_one(struct sk_buff *skb, struct net_device *dev,
379 				  const struct ethnl_dump_ctx *ctx)
380 {
381 	int ret;
382 
383 	ethnl_init_reply_data(ctx->reply_data, ctx->ops, dev);
384 	rtnl_lock();
385 	ret = ctx->ops->prepare_data(ctx->req_info, ctx->reply_data, NULL);
386 	rtnl_unlock();
387 	if (ret < 0)
388 		goto out;
389 	ret = ethnl_fill_reply_header(skb, dev, ctx->ops->hdr_attr);
390 	if (ret < 0)
391 		goto out;
392 	ret = ctx->ops->fill_reply(skb, ctx->req_info, ctx->reply_data);
393 
394 out:
395 	if (ctx->ops->cleanup_data)
396 		ctx->ops->cleanup_data(ctx->reply_data);
397 	ctx->reply_data->dev = NULL;
398 	return ret;
399 }
400 
401 /* Default ->dumpit() handler for GET requests. Device iteration copied from
402  * rtnl_dump_ifinfo(); we have to be more careful about device hashtable
403  * persistence as we cannot guarantee to hold RTNL lock through the whole
404  * function as rtnetnlink does.
405  */
406 static int ethnl_default_dumpit(struct sk_buff *skb,
407 				struct netlink_callback *cb)
408 {
409 	struct ethnl_dump_ctx *ctx = ethnl_dump_context(cb);
410 	struct net *net = sock_net(skb->sk);
411 	int s_idx = ctx->pos_idx;
412 	int h, idx = 0;
413 	int ret = 0;
414 	void *ehdr;
415 
416 	rtnl_lock();
417 	for (h = ctx->pos_hash; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
418 		struct hlist_head *head;
419 		struct net_device *dev;
420 		unsigned int seq;
421 
422 		head = &net->dev_index_head[h];
423 
424 restart_chain:
425 		seq = net->dev_base_seq;
426 		cb->seq = seq;
427 		idx = 0;
428 		hlist_for_each_entry(dev, head, index_hlist) {
429 			if (idx < s_idx)
430 				goto cont;
431 			dev_hold(dev);
432 			rtnl_unlock();
433 
434 			ehdr = genlmsg_put(skb, NETLINK_CB(cb->skb).portid,
435 					   cb->nlh->nlmsg_seq,
436 					   &ethtool_genl_family, 0,
437 					   ctx->ops->reply_cmd);
438 			if (!ehdr) {
439 				dev_put(dev);
440 				ret = -EMSGSIZE;
441 				goto out;
442 			}
443 			ret = ethnl_default_dump_one(skb, dev, ctx);
444 			dev_put(dev);
445 			if (ret < 0) {
446 				genlmsg_cancel(skb, ehdr);
447 				if (ret == -EOPNOTSUPP)
448 					goto lock_and_cont;
449 				if (likely(skb->len))
450 					ret = skb->len;
451 				goto out;
452 			}
453 			genlmsg_end(skb, ehdr);
454 lock_and_cont:
455 			rtnl_lock();
456 			if (net->dev_base_seq != seq) {
457 				s_idx = idx + 1;
458 				goto restart_chain;
459 			}
460 cont:
461 			idx++;
462 		}
463 
464 	}
465 	rtnl_unlock();
466 
467 out:
468 	ctx->pos_hash = h;
469 	ctx->pos_idx = idx;
470 	nl_dump_check_consistent(cb, nlmsg_hdr(skb));
471 
472 	return ret;
473 }
474 
475 /* generic ->start() handler for GET requests */
476 static int ethnl_default_start(struct netlink_callback *cb)
477 {
478 	struct ethnl_dump_ctx *ctx = ethnl_dump_context(cb);
479 	struct ethnl_reply_data *reply_data;
480 	const struct ethnl_request_ops *ops;
481 	struct ethnl_req_info *req_info;
482 	struct genlmsghdr *ghdr;
483 	int ret;
484 
485 	BUILD_BUG_ON(sizeof(*ctx) > sizeof(cb->ctx));
486 
487 	ghdr = nlmsg_data(cb->nlh);
488 	ops = ethnl_default_requests[ghdr->cmd];
489 	if (WARN_ONCE(!ops, "cmd %u has no ethnl_request_ops\n", ghdr->cmd))
490 		return -EOPNOTSUPP;
491 	req_info = kzalloc(ops->req_info_size, GFP_KERNEL);
492 	if (!req_info)
493 		return -ENOMEM;
494 	reply_data = kmalloc(ops->reply_data_size, GFP_KERNEL);
495 	if (!reply_data) {
496 		ret = -ENOMEM;
497 		goto free_req_info;
498 	}
499 
500 	ret = ethnl_default_parse(req_info, cb->nlh, sock_net(cb->skb->sk), ops,
501 				  cb->extack, false);
502 	if (req_info->dev) {
503 		/* We ignore device specification in dump requests but as the
504 		 * same parser as for non-dump (doit) requests is used, it
505 		 * would take reference to the device if it finds one
506 		 */
507 		dev_put(req_info->dev);
508 		req_info->dev = NULL;
509 	}
510 	if (ret < 0)
511 		goto free_reply_data;
512 
513 	ctx->ops = ops;
514 	ctx->req_info = req_info;
515 	ctx->reply_data = reply_data;
516 	ctx->pos_hash = 0;
517 	ctx->pos_idx = 0;
518 
519 	return 0;
520 
521 free_reply_data:
522 	kfree(reply_data);
523 free_req_info:
524 	kfree(req_info);
525 
526 	return ret;
527 }
528 
529 /* default ->done() handler for GET requests */
530 static int ethnl_default_done(struct netlink_callback *cb)
531 {
532 	struct ethnl_dump_ctx *ctx = ethnl_dump_context(cb);
533 
534 	kfree(ctx->reply_data);
535 	kfree(ctx->req_info);
536 
537 	return 0;
538 }
539 
540 static const struct ethnl_request_ops *
541 ethnl_default_notify_ops[ETHTOOL_MSG_KERNEL_MAX + 1] = {
542 	[ETHTOOL_MSG_LINKINFO_NTF]	= &ethnl_linkinfo_request_ops,
543 	[ETHTOOL_MSG_LINKMODES_NTF]	= &ethnl_linkmodes_request_ops,
544 	[ETHTOOL_MSG_DEBUG_NTF]		= &ethnl_debug_request_ops,
545 	[ETHTOOL_MSG_WOL_NTF]		= &ethnl_wol_request_ops,
546 	[ETHTOOL_MSG_FEATURES_NTF]	= &ethnl_features_request_ops,
547 	[ETHTOOL_MSG_PRIVFLAGS_NTF]	= &ethnl_privflags_request_ops,
548 	[ETHTOOL_MSG_RINGS_NTF]		= &ethnl_rings_request_ops,
549 	[ETHTOOL_MSG_CHANNELS_NTF]	= &ethnl_channels_request_ops,
550 	[ETHTOOL_MSG_COALESCE_NTF]	= &ethnl_coalesce_request_ops,
551 	[ETHTOOL_MSG_PAUSE_NTF]		= &ethnl_pause_request_ops,
552 	[ETHTOOL_MSG_EEE_NTF]		= &ethnl_eee_request_ops,
553 };
554 
555 /* default notification handler */
556 static void ethnl_default_notify(struct net_device *dev, unsigned int cmd,
557 				 const void *data)
558 {
559 	struct ethnl_reply_data *reply_data;
560 	const struct ethnl_request_ops *ops;
561 	struct ethnl_req_info *req_info;
562 	struct sk_buff *skb;
563 	void *reply_payload;
564 	int reply_len;
565 	int ret;
566 
567 	if (WARN_ONCE(cmd > ETHTOOL_MSG_KERNEL_MAX ||
568 		      !ethnl_default_notify_ops[cmd],
569 		      "unexpected notification type %u\n", cmd))
570 		return;
571 	ops = ethnl_default_notify_ops[cmd];
572 	req_info = kzalloc(ops->req_info_size, GFP_KERNEL);
573 	if (!req_info)
574 		return;
575 	reply_data = kmalloc(ops->reply_data_size, GFP_KERNEL);
576 	if (!reply_data) {
577 		kfree(req_info);
578 		return;
579 	}
580 
581 	req_info->dev = dev;
582 	req_info->flags |= ETHTOOL_FLAG_COMPACT_BITSETS;
583 
584 	ethnl_init_reply_data(reply_data, ops, dev);
585 	ret = ops->prepare_data(req_info, reply_data, NULL);
586 	if (ret < 0)
587 		goto err_cleanup;
588 	ret = ops->reply_size(req_info, reply_data);
589 	if (ret < 0)
590 		goto err_cleanup;
591 	reply_len = ret + ethnl_reply_header_size();
592 	ret = -ENOMEM;
593 	skb = genlmsg_new(reply_len, GFP_KERNEL);
594 	if (!skb)
595 		goto err_cleanup;
596 	reply_payload = ethnl_bcastmsg_put(skb, cmd);
597 	if (!reply_payload)
598 		goto err_skb;
599 	ret = ethnl_fill_reply_header(skb, dev, ops->hdr_attr);
600 	if (ret < 0)
601 		goto err_msg;
602 	ret = ops->fill_reply(skb, req_info, reply_data);
603 	if (ret < 0)
604 		goto err_msg;
605 	if (ops->cleanup_data)
606 		ops->cleanup_data(reply_data);
607 
608 	genlmsg_end(skb, reply_payload);
609 	kfree(reply_data);
610 	kfree(req_info);
611 	ethnl_multicast(skb, dev);
612 	return;
613 
614 err_msg:
615 	WARN_ONCE(ret == -EMSGSIZE,
616 		  "calculated message payload length (%d) not sufficient\n",
617 		  reply_len);
618 err_skb:
619 	nlmsg_free(skb);
620 err_cleanup:
621 	if (ops->cleanup_data)
622 		ops->cleanup_data(reply_data);
623 	kfree(reply_data);
624 	kfree(req_info);
625 	return;
626 }
627 
628 /* notifications */
629 
630 typedef void (*ethnl_notify_handler_t)(struct net_device *dev, unsigned int cmd,
631 				       const void *data);
632 
633 static const ethnl_notify_handler_t ethnl_notify_handlers[] = {
634 	[ETHTOOL_MSG_LINKINFO_NTF]	= ethnl_default_notify,
635 	[ETHTOOL_MSG_LINKMODES_NTF]	= ethnl_default_notify,
636 	[ETHTOOL_MSG_DEBUG_NTF]		= ethnl_default_notify,
637 	[ETHTOOL_MSG_WOL_NTF]		= ethnl_default_notify,
638 	[ETHTOOL_MSG_FEATURES_NTF]	= ethnl_default_notify,
639 	[ETHTOOL_MSG_PRIVFLAGS_NTF]	= ethnl_default_notify,
640 	[ETHTOOL_MSG_RINGS_NTF]		= ethnl_default_notify,
641 	[ETHTOOL_MSG_CHANNELS_NTF]	= ethnl_default_notify,
642 	[ETHTOOL_MSG_COALESCE_NTF]	= ethnl_default_notify,
643 	[ETHTOOL_MSG_PAUSE_NTF]		= ethnl_default_notify,
644 	[ETHTOOL_MSG_EEE_NTF]		= ethnl_default_notify,
645 };
646 
647 void ethtool_notify(struct net_device *dev, unsigned int cmd, const void *data)
648 {
649 	if (unlikely(!ethnl_ok))
650 		return;
651 	ASSERT_RTNL();
652 
653 	if (likely(cmd < ARRAY_SIZE(ethnl_notify_handlers) &&
654 		   ethnl_notify_handlers[cmd]))
655 		ethnl_notify_handlers[cmd](dev, cmd, data);
656 	else
657 		WARN_ONCE(1, "notification %u not implemented (dev=%s)\n",
658 			  cmd, netdev_name(dev));
659 }
660 EXPORT_SYMBOL(ethtool_notify);
661 
662 static void ethnl_notify_features(struct netdev_notifier_info *info)
663 {
664 	struct net_device *dev = netdev_notifier_info_to_dev(info);
665 
666 	ethtool_notify(dev, ETHTOOL_MSG_FEATURES_NTF, NULL);
667 }
668 
669 static int ethnl_netdev_event(struct notifier_block *this, unsigned long event,
670 			      void *ptr)
671 {
672 	switch (event) {
673 	case NETDEV_FEAT_CHANGE:
674 		ethnl_notify_features(ptr);
675 		break;
676 	}
677 
678 	return NOTIFY_DONE;
679 }
680 
681 static struct notifier_block ethnl_netdev_notifier = {
682 	.notifier_call = ethnl_netdev_event,
683 };
684 
685 /* genetlink setup */
686 
687 static const struct genl_ops ethtool_genl_ops[] = {
688 	{
689 		.cmd	= ETHTOOL_MSG_STRSET_GET,
690 		.doit	= ethnl_default_doit,
691 		.start	= ethnl_default_start,
692 		.dumpit	= ethnl_default_dumpit,
693 		.done	= ethnl_default_done,
694 	},
695 	{
696 		.cmd	= ETHTOOL_MSG_LINKINFO_GET,
697 		.doit	= ethnl_default_doit,
698 		.start	= ethnl_default_start,
699 		.dumpit	= ethnl_default_dumpit,
700 		.done	= ethnl_default_done,
701 	},
702 	{
703 		.cmd	= ETHTOOL_MSG_LINKINFO_SET,
704 		.flags	= GENL_UNS_ADMIN_PERM,
705 		.doit	= ethnl_set_linkinfo,
706 	},
707 	{
708 		.cmd	= ETHTOOL_MSG_LINKMODES_GET,
709 		.doit	= ethnl_default_doit,
710 		.start	= ethnl_default_start,
711 		.dumpit	= ethnl_default_dumpit,
712 		.done	= ethnl_default_done,
713 	},
714 	{
715 		.cmd	= ETHTOOL_MSG_LINKMODES_SET,
716 		.flags	= GENL_UNS_ADMIN_PERM,
717 		.doit	= ethnl_set_linkmodes,
718 	},
719 	{
720 		.cmd	= ETHTOOL_MSG_LINKSTATE_GET,
721 		.doit	= ethnl_default_doit,
722 		.start	= ethnl_default_start,
723 		.dumpit	= ethnl_default_dumpit,
724 		.done	= ethnl_default_done,
725 	},
726 	{
727 		.cmd	= ETHTOOL_MSG_DEBUG_GET,
728 		.doit	= ethnl_default_doit,
729 		.start	= ethnl_default_start,
730 		.dumpit	= ethnl_default_dumpit,
731 		.done	= ethnl_default_done,
732 	},
733 	{
734 		.cmd	= ETHTOOL_MSG_DEBUG_SET,
735 		.flags	= GENL_UNS_ADMIN_PERM,
736 		.doit	= ethnl_set_debug,
737 	},
738 	{
739 		.cmd	= ETHTOOL_MSG_WOL_GET,
740 		.flags	= GENL_UNS_ADMIN_PERM,
741 		.doit	= ethnl_default_doit,
742 		.start	= ethnl_default_start,
743 		.dumpit	= ethnl_default_dumpit,
744 		.done	= ethnl_default_done,
745 	},
746 	{
747 		.cmd	= ETHTOOL_MSG_WOL_SET,
748 		.flags	= GENL_UNS_ADMIN_PERM,
749 		.doit	= ethnl_set_wol,
750 	},
751 	{
752 		.cmd	= ETHTOOL_MSG_FEATURES_GET,
753 		.doit	= ethnl_default_doit,
754 		.start	= ethnl_default_start,
755 		.dumpit	= ethnl_default_dumpit,
756 		.done	= ethnl_default_done,
757 	},
758 	{
759 		.cmd	= ETHTOOL_MSG_FEATURES_SET,
760 		.flags	= GENL_UNS_ADMIN_PERM,
761 		.doit	= ethnl_set_features,
762 	},
763 	{
764 		.cmd	= ETHTOOL_MSG_PRIVFLAGS_GET,
765 		.doit	= ethnl_default_doit,
766 		.start	= ethnl_default_start,
767 		.dumpit	= ethnl_default_dumpit,
768 		.done	= ethnl_default_done,
769 	},
770 	{
771 		.cmd	= ETHTOOL_MSG_PRIVFLAGS_SET,
772 		.flags	= GENL_UNS_ADMIN_PERM,
773 		.doit	= ethnl_set_privflags,
774 	},
775 	{
776 		.cmd	= ETHTOOL_MSG_RINGS_GET,
777 		.doit	= ethnl_default_doit,
778 		.start	= ethnl_default_start,
779 		.dumpit	= ethnl_default_dumpit,
780 		.done	= ethnl_default_done,
781 	},
782 	{
783 		.cmd	= ETHTOOL_MSG_RINGS_SET,
784 		.flags	= GENL_UNS_ADMIN_PERM,
785 		.doit	= ethnl_set_rings,
786 	},
787 	{
788 		.cmd	= ETHTOOL_MSG_CHANNELS_GET,
789 		.doit	= ethnl_default_doit,
790 		.start	= ethnl_default_start,
791 		.dumpit	= ethnl_default_dumpit,
792 		.done	= ethnl_default_done,
793 	},
794 	{
795 		.cmd	= ETHTOOL_MSG_CHANNELS_SET,
796 		.flags	= GENL_UNS_ADMIN_PERM,
797 		.doit	= ethnl_set_channels,
798 	},
799 	{
800 		.cmd	= ETHTOOL_MSG_COALESCE_GET,
801 		.doit	= ethnl_default_doit,
802 		.start	= ethnl_default_start,
803 		.dumpit	= ethnl_default_dumpit,
804 		.done	= ethnl_default_done,
805 	},
806 	{
807 		.cmd	= ETHTOOL_MSG_COALESCE_SET,
808 		.flags	= GENL_UNS_ADMIN_PERM,
809 		.doit	= ethnl_set_coalesce,
810 	},
811 	{
812 		.cmd	= ETHTOOL_MSG_PAUSE_GET,
813 		.doit	= ethnl_default_doit,
814 		.start	= ethnl_default_start,
815 		.dumpit	= ethnl_default_dumpit,
816 		.done	= ethnl_default_done,
817 	},
818 	{
819 		.cmd	= ETHTOOL_MSG_PAUSE_SET,
820 		.flags	= GENL_UNS_ADMIN_PERM,
821 		.doit	= ethnl_set_pause,
822 	},
823 	{
824 		.cmd	= ETHTOOL_MSG_EEE_GET,
825 		.doit	= ethnl_default_doit,
826 		.start	= ethnl_default_start,
827 		.dumpit	= ethnl_default_dumpit,
828 		.done	= ethnl_default_done,
829 	},
830 	{
831 		.cmd	= ETHTOOL_MSG_EEE_SET,
832 		.flags	= GENL_UNS_ADMIN_PERM,
833 		.doit	= ethnl_set_eee,
834 	},
835 	{
836 		.cmd	= ETHTOOL_MSG_TSINFO_GET,
837 		.doit	= ethnl_default_doit,
838 		.start	= ethnl_default_start,
839 		.dumpit	= ethnl_default_dumpit,
840 		.done	= ethnl_default_done,
841 	},
842 	{
843 		.cmd	= ETHTOOL_MSG_CABLE_TEST_ACT,
844 		.flags	= GENL_UNS_ADMIN_PERM,
845 		.doit	= ethnl_act_cable_test,
846 	},
847 	{
848 		.cmd	= ETHTOOL_MSG_CABLE_TEST_TDR_ACT,
849 		.flags	= GENL_UNS_ADMIN_PERM,
850 		.doit	= ethnl_act_cable_test_tdr,
851 	},
852 };
853 
854 static const struct genl_multicast_group ethtool_nl_mcgrps[] = {
855 	[ETHNL_MCGRP_MONITOR] = { .name = ETHTOOL_MCGRP_MONITOR_NAME },
856 };
857 
858 static struct genl_family ethtool_genl_family = {
859 	.name		= ETHTOOL_GENL_NAME,
860 	.version	= ETHTOOL_GENL_VERSION,
861 	.netnsok	= true,
862 	.parallel_ops	= true,
863 	.ops		= ethtool_genl_ops,
864 	.n_ops		= ARRAY_SIZE(ethtool_genl_ops),
865 	.mcgrps		= ethtool_nl_mcgrps,
866 	.n_mcgrps	= ARRAY_SIZE(ethtool_nl_mcgrps),
867 };
868 
869 /* module setup */
870 
871 static int __init ethnl_init(void)
872 {
873 	int ret;
874 
875 	ret = genl_register_family(&ethtool_genl_family);
876 	if (WARN(ret < 0, "ethtool: genetlink family registration failed"))
877 		return ret;
878 	ethnl_ok = true;
879 
880 	ret = register_netdevice_notifier(&ethnl_netdev_notifier);
881 	WARN(ret < 0, "ethtool: net device notifier registration failed");
882 	return ret;
883 }
884 
885 subsys_initcall(ethnl_init);
886