1 // SPDX-License-Identifier: GPL-2.0
3 * NETLINK Generic Netlink Family
5 * Authors: Jamal Hadi Salim
6 * Thomas Graf <tgraf@suug.ch>
7 * Johannes Berg <johannes@sipsolutions.net>
10 #include <linux/module.h>
11 #include <linux/kernel.h>
12 #include <linux/slab.h>
13 #include <linux/errno.h>
14 #include <linux/types.h>
15 #include <linux/socket.h>
16 #include <linux/string_helpers.h>
17 #include <linux/skbuff.h>
18 #include <linux/mutex.h>
19 #include <linux/bitmap.h>
20 #include <linux/rwsem.h>
21 #include <linux/idr.h>
23 #include <net/genetlink.h>
25 static DEFINE_MUTEX(genl_mutex); /* serialization of message processing */
26 static DECLARE_RWSEM(cb_lock);
28 atomic_t genl_sk_destructing_cnt = ATOMIC_INIT(0);
29 DECLARE_WAIT_QUEUE_HEAD(genl_sk_destructing_waitq);
33 mutex_lock(&genl_mutex);
35 EXPORT_SYMBOL(genl_lock);
37 void genl_unlock(void)
39 mutex_unlock(&genl_mutex);
41 EXPORT_SYMBOL(genl_unlock);
43 static void genl_lock_all(void)
49 static void genl_unlock_all(void)
55 static void genl_op_lock(const struct genl_family *family)
57 if (!family->parallel_ops)
61 static void genl_op_unlock(const struct genl_family *family)
63 if (!family->parallel_ops)
67 static DEFINE_IDR(genl_fam_idr);
70 * Bitmap of multicast groups that are currently in use.
72 * To avoid an allocation at boot of just one unsigned long,
73 * declare it global instead.
74 * Bit 0 is marked as already used since group 0 is invalid.
75 * Bit 1 is marked as already used since the drop-monitor code
76 * abuses the API and thinks it can statically use group 1.
77 * That group will typically conflict with other groups that
78 * any proper users use.
79 * Bit 16 is marked as used since it's used for generic netlink
80 * and the code no longer marks pre-reserved IDs as used.
81 * Bit 17 is marked as already used since the VFS quota code
82 * also abused this API and relied on family == group ID, we
83 * cater to that by giving it a static family and group ID.
84 * Bit 18 is marked as already used since the PMCRAID driver
85 * did the same thing as the VFS quota code (maybe copied?)
87 static unsigned long mc_group_start = 0x3 | BIT(GENL_ID_CTRL) |
88 BIT(GENL_ID_VFS_DQUOT) |
90 static unsigned long *mc_groups = &mc_group_start;
91 static unsigned long mc_groups_longs = 1;
93 /* We need the last attribute with non-zero ID therefore a 2-entry array */
94 static struct nla_policy genl_policy_reject_all[] = {
95 { .type = NLA_REJECT },
96 { .type = NLA_REJECT },
99 static int genl_ctrl_event(int event, const struct genl_family *family,
100 const struct genl_multicast_group *grp,
104 genl_op_fill_in_reject_policy(const struct genl_family *family,
107 BUILD_BUG_ON(ARRAY_SIZE(genl_policy_reject_all) - 1 != 1);
109 if (op->policy || op->cmd < family->resv_start_op)
112 op->policy = genl_policy_reject_all;
117 genl_op_fill_in_reject_policy_split(const struct genl_family *family,
118 struct genl_split_ops *op)
123 op->policy = genl_policy_reject_all;
127 static const struct genl_family *genl_family_find_byid(unsigned int id)
129 return idr_find(&genl_fam_idr, id);
132 static const struct genl_family *genl_family_find_byname(char *name)
134 const struct genl_family *family;
137 idr_for_each_entry(&genl_fam_idr, family, id)
138 if (strcmp(family->name, name) == 0)
144 struct genl_op_iter {
145 const struct genl_family *family;
146 struct genl_split_ops doit;
147 struct genl_split_ops dumpit;
154 static void genl_op_from_full(const struct genl_family *family,
155 unsigned int i, struct genl_ops *op)
157 *op = family->ops[i];
160 op->maxattr = family->maxattr;
162 op->policy = family->policy;
164 genl_op_fill_in_reject_policy(family, op);
167 static int genl_get_cmd_full(u32 cmd, const struct genl_family *family,
172 for (i = 0; i < family->n_ops; i++)
173 if (family->ops[i].cmd == cmd) {
174 genl_op_from_full(family, i, op);
181 static void genl_op_from_small(const struct genl_family *family,
182 unsigned int i, struct genl_ops *op)
184 memset(op, 0, sizeof(*op));
185 op->doit = family->small_ops[i].doit;
186 op->dumpit = family->small_ops[i].dumpit;
187 op->cmd = family->small_ops[i].cmd;
188 op->internal_flags = family->small_ops[i].internal_flags;
189 op->flags = family->small_ops[i].flags;
190 op->validate = family->small_ops[i].validate;
192 op->maxattr = family->maxattr;
193 op->policy = family->policy;
195 genl_op_fill_in_reject_policy(family, op);
198 static int genl_get_cmd_small(u32 cmd, const struct genl_family *family,
203 for (i = 0; i < family->n_small_ops; i++)
204 if (family->small_ops[i].cmd == cmd) {
205 genl_op_from_small(family, i, op);
212 static void genl_op_from_split(struct genl_op_iter *iter)
214 const struct genl_family *family = iter->family;
217 i = iter->entry_idx - family->n_ops - family->n_small_ops;
219 if (family->split_ops[i + cnt].flags & GENL_CMD_CAP_DO) {
220 iter->doit = family->split_ops[i + cnt];
221 genl_op_fill_in_reject_policy_split(family, &iter->doit);
224 memset(&iter->doit, 0, sizeof(iter->doit));
227 if (i + cnt < family->n_split_ops &&
228 family->split_ops[i + cnt].flags & GENL_CMD_CAP_DUMP &&
229 (!cnt || family->split_ops[i + cnt].cmd == iter->doit.cmd)) {
230 iter->dumpit = family->split_ops[i + cnt];
231 genl_op_fill_in_reject_policy_split(family, &iter->dumpit);
234 memset(&iter->dumpit, 0, sizeof(iter->dumpit));
238 iter->entry_idx += cnt;
242 genl_get_cmd_split(u32 cmd, u8 flag, const struct genl_family *family,
243 struct genl_split_ops *op)
247 for (i = 0; i < family->n_split_ops; i++)
248 if (family->split_ops[i].cmd == cmd &&
249 family->split_ops[i].flags & flag) {
250 *op = family->split_ops[i];
258 genl_cmd_full_to_split(struct genl_split_ops *op,
259 const struct genl_family *family,
260 const struct genl_ops *full, u8 flags)
262 if ((flags & GENL_CMD_CAP_DO && !full->doit) ||
263 (flags & GENL_CMD_CAP_DUMP && !full->dumpit)) {
264 memset(op, 0, sizeof(*op));
268 if (flags & GENL_CMD_CAP_DUMP) {
269 op->start = full->start;
270 op->dumpit = full->dumpit;
271 op->done = full->done;
273 op->pre_doit = family->pre_doit;
274 op->doit = full->doit;
275 op->post_doit = family->post_doit;
278 if (flags & GENL_CMD_CAP_DUMP &&
279 full->validate & GENL_DONT_VALIDATE_DUMP) {
283 op->policy = full->policy;
284 op->maxattr = full->maxattr;
288 op->internal_flags = full->internal_flags;
289 op->flags = full->flags;
290 op->validate = full->validate;
292 /* Make sure flags include the GENL_CMD_CAP_DO / GENL_CMD_CAP_DUMP */
298 /* Must make sure that op is initialized to 0 on failure */
300 genl_get_cmd(u32 cmd, u8 flags, const struct genl_family *family,
301 struct genl_split_ops *op)
303 struct genl_ops full;
306 err = genl_get_cmd_full(cmd, family, &full);
308 err = genl_get_cmd_small(cmd, family, &full);
309 /* Found one of legacy forms */
311 return genl_cmd_full_to_split(op, family, &full, flags);
313 err = genl_get_cmd_split(cmd, flags, family, op);
315 memset(op, 0, sizeof(*op));
319 /* For policy dumping only, get ops of both do and dump.
320 * Fail if both are missing, genl_get_cmd() will zero-init in case of failure.
323 genl_get_cmd_both(u32 cmd, const struct genl_family *family,
324 struct genl_split_ops *doit, struct genl_split_ops *dumpit)
328 err1 = genl_get_cmd(cmd, GENL_CMD_CAP_DO, family, doit);
329 err2 = genl_get_cmd(cmd, GENL_CMD_CAP_DUMP, family, dumpit);
331 return err1 && err2 ? -ENOENT : 0;
335 genl_op_iter_init(const struct genl_family *family, struct genl_op_iter *iter)
337 iter->family = family;
343 return iter->family->n_ops +
344 iter->family->n_small_ops +
345 iter->family->n_split_ops;
348 static bool genl_op_iter_next(struct genl_op_iter *iter)
350 const struct genl_family *family = iter->family;
351 bool legacy_op = true;
354 if (iter->entry_idx < family->n_ops) {
355 genl_op_from_full(family, iter->entry_idx, &op);
356 } else if (iter->entry_idx < family->n_ops + family->n_small_ops) {
357 genl_op_from_small(family, iter->entry_idx - family->n_ops,
359 } else if (iter->entry_idx <
360 family->n_ops + family->n_small_ops + family->n_split_ops) {
362 /* updates entry_idx */
363 genl_op_from_split(iter);
373 genl_cmd_full_to_split(&iter->doit, family,
374 &op, GENL_CMD_CAP_DO);
375 genl_cmd_full_to_split(&iter->dumpit, family,
376 &op, GENL_CMD_CAP_DUMP);
379 iter->cmd = iter->doit.cmd | iter->dumpit.cmd;
380 iter->flags = iter->doit.flags | iter->dumpit.flags;
386 genl_op_iter_copy(struct genl_op_iter *dst, struct genl_op_iter *src)
391 static unsigned int genl_op_iter_idx(struct genl_op_iter *iter)
393 return iter->cmd_idx;
396 static int genl_allocate_reserve_groups(int n_groups, int *first_id)
398 unsigned long *new_groups;
406 id = find_first_zero_bit(mc_groups,
410 id = find_next_zero_bit(mc_groups,
411 mc_groups_longs * BITS_PER_LONG,
416 i < min_t(int, id + n_groups,
417 mc_groups_longs * BITS_PER_LONG);
419 if (test_bit(i, mc_groups)) {
426 if (id + n_groups > mc_groups_longs * BITS_PER_LONG) {
427 unsigned long new_longs = mc_groups_longs +
428 BITS_TO_LONGS(n_groups);
429 size_t nlen = new_longs * sizeof(unsigned long);
431 if (mc_groups == &mc_group_start) {
432 new_groups = kzalloc(nlen, GFP_KERNEL);
435 mc_groups = new_groups;
436 *mc_groups = mc_group_start;
438 new_groups = krealloc(mc_groups, nlen,
442 mc_groups = new_groups;
443 for (i = 0; i < BITS_TO_LONGS(n_groups); i++)
444 mc_groups[mc_groups_longs + i] = 0;
446 mc_groups_longs = new_longs;
450 for (i = id; i < id + n_groups; i++)
451 set_bit(i, mc_groups);
456 static struct genl_family genl_ctrl;
458 static int genl_validate_assign_mc_groups(struct genl_family *family)
461 int n_groups = family->n_mcgrps;
463 bool groups_allocated = false;
468 for (i = 0; i < n_groups; i++) {
469 const struct genl_multicast_group *grp = &family->mcgrps[i];
471 if (WARN_ON(grp->name[0] == '\0'))
473 if (WARN_ON(!string_is_terminated(grp->name, GENL_NAMSIZ)))
477 /* special-case our own group and hacks */
478 if (family == &genl_ctrl) {
479 first_id = GENL_ID_CTRL;
480 BUG_ON(n_groups != 1);
481 } else if (strcmp(family->name, "NET_DM") == 0) {
483 BUG_ON(n_groups != 1);
484 } else if (family->id == GENL_ID_VFS_DQUOT) {
485 first_id = GENL_ID_VFS_DQUOT;
486 BUG_ON(n_groups != 1);
487 } else if (family->id == GENL_ID_PMCRAID) {
488 first_id = GENL_ID_PMCRAID;
489 BUG_ON(n_groups != 1);
491 groups_allocated = true;
492 err = genl_allocate_reserve_groups(n_groups, &first_id);
497 family->mcgrp_offset = first_id;
499 /* if still initializing, can't and don't need to realloc bitmaps */
500 if (!init_net.genl_sock)
503 if (family->netnsok) {
506 netlink_table_grab();
508 for_each_net_rcu(net) {
509 err = __netlink_change_ngroups(net->genl_sock,
510 mc_groups_longs * BITS_PER_LONG);
513 * No need to roll back, can only fail if
514 * memory allocation fails and then the
515 * number of _possible_ groups has been
516 * increased on some sockets which is ok.
522 netlink_table_ungrab();
524 err = netlink_change_ngroups(init_net.genl_sock,
525 mc_groups_longs * BITS_PER_LONG);
528 if (groups_allocated && err) {
529 for (i = 0; i < family->n_mcgrps; i++)
530 clear_bit(family->mcgrp_offset + i, mc_groups);
536 static void genl_unregister_mc_groups(const struct genl_family *family)
541 netlink_table_grab();
543 for_each_net_rcu(net) {
544 for (i = 0; i < family->n_mcgrps; i++)
545 __netlink_clear_multicast_users(
546 net->genl_sock, family->mcgrp_offset + i);
549 netlink_table_ungrab();
551 for (i = 0; i < family->n_mcgrps; i++) {
552 int grp_id = family->mcgrp_offset + i;
555 clear_bit(grp_id, mc_groups);
556 genl_ctrl_event(CTRL_CMD_DELMCAST_GRP, family,
557 &family->mcgrps[i], grp_id);
561 static bool genl_split_op_check(const struct genl_split_ops *op)
563 if (WARN_ON(hweight8(op->flags & (GENL_CMD_CAP_DO |
564 GENL_CMD_CAP_DUMP)) != 1))
569 static int genl_validate_ops(const struct genl_family *family)
571 struct genl_op_iter i, j;
574 if (WARN_ON(family->n_ops && !family->ops) ||
575 WARN_ON(family->n_small_ops && !family->small_ops) ||
576 WARN_ON(family->n_split_ops && !family->split_ops))
579 for (genl_op_iter_init(family, &i); genl_op_iter_next(&i); ) {
580 if (!(i.flags & (GENL_CMD_CAP_DO | GENL_CMD_CAP_DUMP)))
583 if (WARN_ON(i.cmd >= family->resv_start_op &&
584 (i.doit.validate || i.dumpit.validate)))
587 genl_op_iter_copy(&j, &i);
588 while (genl_op_iter_next(&j)) {
594 if (family->n_split_ops) {
595 if (genl_split_op_check(&family->split_ops[0]))
599 for (s = 1; s < family->n_split_ops; s++) {
600 const struct genl_split_ops *a, *b;
602 a = &family->split_ops[s - 1];
603 b = &family->split_ops[s];
605 if (genl_split_op_check(b))
608 /* Check sort order */
609 if (a->cmd < b->cmd) {
611 } else if (a->cmd > b->cmd) {
616 if (a->internal_flags != b->internal_flags ||
617 ((a->flags ^ b->flags) & ~(GENL_CMD_CAP_DO |
618 GENL_CMD_CAP_DUMP))) {
623 if ((a->flags & GENL_CMD_CAP_DO) &&
624 (b->flags & GENL_CMD_CAP_DUMP))
634 static void *genl_sk_priv_alloc(struct genl_family *family)
638 priv = kzalloc(family->sock_priv_size, GFP_KERNEL);
640 return ERR_PTR(-ENOMEM);
642 if (family->sock_priv_init)
643 family->sock_priv_init(priv);
648 static void genl_sk_priv_free(const struct genl_family *family, void *priv)
650 if (family->sock_priv_destroy)
651 family->sock_priv_destroy(priv);
655 static int genl_sk_privs_alloc(struct genl_family *family)
657 if (!family->sock_priv_size)
660 family->sock_privs = kzalloc(sizeof(*family->sock_privs), GFP_KERNEL);
661 if (!family->sock_privs)
663 xa_init(family->sock_privs);
667 static void genl_sk_privs_free(const struct genl_family *family)
672 if (!family->sock_priv_size)
675 xa_for_each(family->sock_privs, id, priv)
676 genl_sk_priv_free(family, priv);
678 xa_destroy(family->sock_privs);
679 kfree(family->sock_privs);
682 static void genl_sk_priv_free_by_sock(struct genl_family *family,
687 if (!family->sock_priv_size)
689 priv = xa_erase(family->sock_privs, (unsigned long) sk);
692 genl_sk_priv_free(family, priv);
695 static void genl_release(struct sock *sk, unsigned long *groups)
697 struct genl_family *family;
702 idr_for_each_entry(&genl_fam_idr, family, id)
703 genl_sk_priv_free_by_sock(family, sk);
709 * __genl_sk_priv_get - Get family private pointer for socket, if exists
714 * Lookup a private memory for a Generic netlink family and specified socket.
716 * Caller should make sure this is called in RCU read locked section.
718 * Return: valid pointer on success, otherwise negative error value
719 * encoded by ERR_PTR(), NULL in case priv does not exist.
721 void *__genl_sk_priv_get(struct genl_family *family, struct sock *sk)
723 if (WARN_ON_ONCE(!family->sock_privs))
724 return ERR_PTR(-EINVAL);
725 return xa_load(family->sock_privs, (unsigned long) sk);
729 * genl_sk_priv_get - Get family private pointer for socket
734 * Lookup a private memory for a Generic netlink family and specified socket.
735 * Allocate the private memory in case it was not already done.
737 * Return: valid pointer on success, otherwise negative error value
738 * encoded by ERR_PTR().
740 void *genl_sk_priv_get(struct genl_family *family, struct sock *sk)
742 void *priv, *old_priv;
744 priv = __genl_sk_priv_get(family, sk);
748 /* priv for the family does not exist so far, create it. */
750 priv = genl_sk_priv_alloc(family);
752 return ERR_CAST(priv);
754 old_priv = xa_cmpxchg(family->sock_privs, (unsigned long) sk, NULL,
757 genl_sk_priv_free(family, priv);
758 if (xa_is_err(old_priv))
759 return ERR_PTR(xa_err(old_priv));
760 /* Race happened, priv for the socket was already inserted. */
767 * genl_register_family - register a generic netlink family
768 * @family: generic netlink family
770 * Registers the specified family after validating it first. Only one
771 * family may be registered with the same family name or identifier.
773 * The family's ops, multicast groups and module pointer must already
776 * Return 0 on success or a negative error code.
778 int genl_register_family(struct genl_family *family)
781 int start = GENL_START_ALLOC, end = GENL_MAX_ID;
783 err = genl_validate_ops(family);
789 if (genl_family_find_byname(family->name)) {
794 err = genl_sk_privs_alloc(family);
799 * Sadly, a few cases need to be special-cased
800 * due to them having previously abused the API
801 * and having used their family ID also as their
802 * multicast group ID, so we use reserved IDs
803 * for both to be sure we can do that mapping.
805 if (family == &genl_ctrl) {
806 /* and this needs to be special for initial family lookups */
807 start = end = GENL_ID_CTRL;
808 } else if (strcmp(family->name, "pmcraid") == 0) {
809 start = end = GENL_ID_PMCRAID;
810 } else if (strcmp(family->name, "VFS_DQUOT") == 0) {
811 start = end = GENL_ID_VFS_DQUOT;
814 family->id = idr_alloc_cyclic(&genl_fam_idr, family,
815 start, end + 1, GFP_KERNEL);
816 if (family->id < 0) {
818 goto errout_sk_privs_free;
821 err = genl_validate_assign_mc_groups(family);
827 /* send all events */
828 genl_ctrl_event(CTRL_CMD_NEWFAMILY, family, NULL, 0);
829 for (i = 0; i < family->n_mcgrps; i++)
830 genl_ctrl_event(CTRL_CMD_NEWMCAST_GRP, family,
831 &family->mcgrps[i], family->mcgrp_offset + i);
836 idr_remove(&genl_fam_idr, family->id);
837 errout_sk_privs_free:
838 genl_sk_privs_free(family);
843 EXPORT_SYMBOL(genl_register_family);
846 * genl_unregister_family - unregister generic netlink family
847 * @family: generic netlink family
849 * Unregisters the specified family.
851 * Returns 0 on success or a negative error code.
853 int genl_unregister_family(const struct genl_family *family)
857 if (!genl_family_find_byid(family->id)) {
862 genl_unregister_mc_groups(family);
864 idr_remove(&genl_fam_idr, family->id);
867 wait_event(genl_sk_destructing_waitq,
868 atomic_read(&genl_sk_destructing_cnt) == 0);
870 genl_sk_privs_free(family);
874 genl_ctrl_event(CTRL_CMD_DELFAMILY, family, NULL, 0);
878 EXPORT_SYMBOL(genl_unregister_family);
881 * genlmsg_put - Add generic netlink header to netlink message
882 * @skb: socket buffer holding the message
883 * @portid: netlink portid the message is addressed to
884 * @seq: sequence number (usually the one of the sender)
885 * @family: generic netlink family
886 * @flags: netlink message flags
887 * @cmd: generic netlink command
889 * Returns pointer to user specific header
891 void *genlmsg_put(struct sk_buff *skb, u32 portid, u32 seq,
892 const struct genl_family *family, int flags, u8 cmd)
894 struct nlmsghdr *nlh;
895 struct genlmsghdr *hdr;
897 nlh = nlmsg_put(skb, portid, seq, family->id, GENL_HDRLEN +
898 family->hdrsize, flags);
902 hdr = nlmsg_data(nlh);
904 hdr->version = family->version;
907 return (char *) hdr + GENL_HDRLEN;
909 EXPORT_SYMBOL(genlmsg_put);
911 static struct genl_dumpit_info *genl_dumpit_info_alloc(void)
913 return kmalloc(sizeof(struct genl_dumpit_info), GFP_KERNEL);
916 static void genl_dumpit_info_free(const struct genl_dumpit_info *info)
921 static struct nlattr **
922 genl_family_rcv_msg_attrs_parse(const struct genl_family *family,
923 struct nlmsghdr *nlh,
924 struct netlink_ext_ack *extack,
925 const struct genl_split_ops *ops,
927 enum genl_validate_flags no_strict_flag)
929 enum netlink_validation validate = ops->validate & no_strict_flag ?
930 NL_VALIDATE_LIBERAL :
932 struct nlattr **attrbuf;
938 attrbuf = kmalloc_array(ops->maxattr + 1,
939 sizeof(struct nlattr *), GFP_KERNEL);
941 return ERR_PTR(-ENOMEM);
943 err = __nlmsg_parse(nlh, hdrlen, attrbuf, ops->maxattr, ops->policy,
952 static void genl_family_rcv_msg_attrs_free(struct nlattr **attrbuf)
957 struct genl_start_context {
958 const struct genl_family *family;
959 struct nlmsghdr *nlh;
960 struct netlink_ext_ack *extack;
961 const struct genl_split_ops *ops;
965 static int genl_start(struct netlink_callback *cb)
967 struct genl_start_context *ctx = cb->data;
968 const struct genl_split_ops *ops;
969 struct genl_dumpit_info *info;
970 struct nlattr **attrs = NULL;
974 if (!(ops->validate & GENL_DONT_VALIDATE_DUMP) &&
975 ctx->nlh->nlmsg_len < nlmsg_msg_size(ctx->hdrlen))
978 attrs = genl_family_rcv_msg_attrs_parse(ctx->family, ctx->nlh, ctx->extack,
980 GENL_DONT_VALIDATE_DUMP_STRICT);
982 return PTR_ERR(attrs);
984 info = genl_dumpit_info_alloc();
986 genl_family_rcv_msg_attrs_free(attrs);
990 info->info.family = ctx->family;
991 info->info.snd_seq = cb->nlh->nlmsg_seq;
992 info->info.snd_portid = NETLINK_CB(cb->skb).portid;
993 info->info.nlhdr = cb->nlh;
994 info->info.genlhdr = nlmsg_data(cb->nlh);
995 info->info.attrs = attrs;
996 genl_info_net_set(&info->info, sock_net(cb->skb->sk));
997 info->info.extack = cb->extack;
998 memset(&info->info.user_ptr, 0, sizeof(info->info.user_ptr));
1002 genl_op_lock(ctx->family);
1003 rc = ops->start(cb);
1004 genl_op_unlock(ctx->family);
1008 genl_family_rcv_msg_attrs_free(info->info.attrs);
1009 genl_dumpit_info_free(info);
1015 static int genl_dumpit(struct sk_buff *skb, struct netlink_callback *cb)
1017 struct genl_dumpit_info *dump_info = cb->data;
1018 const struct genl_split_ops *ops = &dump_info->op;
1019 struct genl_info *info = &dump_info->info;
1022 info->extack = cb->extack;
1024 genl_op_lock(info->family);
1025 rc = ops->dumpit(skb, cb);
1026 genl_op_unlock(info->family);
1030 static int genl_done(struct netlink_callback *cb)
1032 struct genl_dumpit_info *dump_info = cb->data;
1033 const struct genl_split_ops *ops = &dump_info->op;
1034 struct genl_info *info = &dump_info->info;
1037 info->extack = cb->extack;
1040 genl_op_lock(info->family);
1042 genl_op_unlock(info->family);
1044 genl_family_rcv_msg_attrs_free(info->attrs);
1045 genl_dumpit_info_free(dump_info);
1049 static int genl_family_rcv_msg_dumpit(const struct genl_family *family,
1050 struct sk_buff *skb,
1051 struct nlmsghdr *nlh,
1052 struct netlink_ext_ack *extack,
1053 const struct genl_split_ops *ops,
1054 int hdrlen, struct net *net)
1056 struct genl_start_context ctx;
1057 struct netlink_dump_control c = {
1058 .module = family->module,
1060 .start = genl_start,
1061 .dump = genl_dumpit,
1067 ctx.family = family;
1069 ctx.extack = extack;
1071 ctx.hdrlen = hdrlen;
1073 genl_op_unlock(family);
1074 err = __netlink_dump_start(net->genl_sock, skb, nlh, &c);
1075 genl_op_lock(family);
1080 static int genl_family_rcv_msg_doit(const struct genl_family *family,
1081 struct sk_buff *skb,
1082 struct nlmsghdr *nlh,
1083 struct netlink_ext_ack *extack,
1084 const struct genl_split_ops *ops,
1085 int hdrlen, struct net *net)
1087 struct nlattr **attrbuf;
1088 struct genl_info info;
1091 attrbuf = genl_family_rcv_msg_attrs_parse(family, nlh, extack,
1093 GENL_DONT_VALIDATE_STRICT);
1094 if (IS_ERR(attrbuf))
1095 return PTR_ERR(attrbuf);
1097 info.snd_seq = nlh->nlmsg_seq;
1098 info.snd_portid = NETLINK_CB(skb).portid;
1099 info.family = family;
1101 info.genlhdr = nlmsg_data(nlh);
1102 info.attrs = attrbuf;
1103 info.extack = extack;
1104 genl_info_net_set(&info, net);
1105 memset(&info.user_ptr, 0, sizeof(info.user_ptr));
1107 if (ops->pre_doit) {
1108 err = ops->pre_doit(ops, skb, &info);
1113 err = ops->doit(skb, &info);
1116 ops->post_doit(ops, skb, &info);
1119 genl_family_rcv_msg_attrs_free(attrbuf);
1124 static int genl_header_check(const struct genl_family *family,
1125 struct nlmsghdr *nlh, struct genlmsghdr *hdr,
1126 struct netlink_ext_ack *extack)
1130 /* Only for commands added after we started validating */
1131 if (hdr->cmd < family->resv_start_op)
1134 if (hdr->reserved) {
1135 NL_SET_ERR_MSG(extack, "genlmsghdr.reserved field is not 0");
1139 /* Old netlink flags have pretty loose semantics, allow only the flags
1140 * consumed by the core where we can enforce the meaning.
1142 flags = nlh->nlmsg_flags;
1143 if ((flags & NLM_F_DUMP) == NLM_F_DUMP) /* DUMP is 2 bits */
1144 flags &= ~NLM_F_DUMP;
1145 if (flags & ~(NLM_F_REQUEST | NLM_F_ACK | NLM_F_ECHO)) {
1146 NL_SET_ERR_MSG(extack,
1147 "ambiguous or reserved bits set in nlmsg_flags");
1154 static int genl_family_rcv_msg(const struct genl_family *family,
1155 struct sk_buff *skb,
1156 struct nlmsghdr *nlh,
1157 struct netlink_ext_ack *extack)
1159 struct net *net = sock_net(skb->sk);
1160 struct genlmsghdr *hdr = nlmsg_data(nlh);
1161 struct genl_split_ops op;
1165 /* this family doesn't exist in this netns */
1166 if (!family->netnsok && !net_eq(net, &init_net))
1169 hdrlen = GENL_HDRLEN + family->hdrsize;
1170 if (nlh->nlmsg_len < nlmsg_msg_size(hdrlen))
1173 if (genl_header_check(family, nlh, hdr, extack))
1176 flags = (nlh->nlmsg_flags & NLM_F_DUMP) == NLM_F_DUMP ?
1177 GENL_CMD_CAP_DUMP : GENL_CMD_CAP_DO;
1178 if (genl_get_cmd(hdr->cmd, flags, family, &op))
1181 if ((op.flags & GENL_ADMIN_PERM) &&
1182 !netlink_capable(skb, CAP_NET_ADMIN))
1185 if ((op.flags & GENL_UNS_ADMIN_PERM) &&
1186 !netlink_ns_capable(skb, net->user_ns, CAP_NET_ADMIN))
1189 if (flags & GENL_CMD_CAP_DUMP)
1190 return genl_family_rcv_msg_dumpit(family, skb, nlh, extack,
1193 return genl_family_rcv_msg_doit(family, skb, nlh, extack,
1197 static int genl_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh,
1198 struct netlink_ext_ack *extack)
1200 const struct genl_family *family;
1203 family = genl_family_find_byid(nlh->nlmsg_type);
1207 genl_op_lock(family);
1208 err = genl_family_rcv_msg(family, skb, nlh, extack);
1209 genl_op_unlock(family);
1214 static void genl_rcv(struct sk_buff *skb)
1216 down_read(&cb_lock);
1217 netlink_rcv_skb(skb, &genl_rcv_msg);
1221 /**************************************************************************
1223 **************************************************************************/
1225 static struct genl_family genl_ctrl;
1227 static int ctrl_fill_info(const struct genl_family *family, u32 portid, u32 seq,
1228 u32 flags, struct sk_buff *skb, u8 cmd)
1230 struct genl_op_iter i;
1233 hdr = genlmsg_put(skb, portid, seq, &genl_ctrl, flags, cmd);
1237 if (nla_put_string(skb, CTRL_ATTR_FAMILY_NAME, family->name) ||
1238 nla_put_u16(skb, CTRL_ATTR_FAMILY_ID, family->id) ||
1239 nla_put_u32(skb, CTRL_ATTR_VERSION, family->version) ||
1240 nla_put_u32(skb, CTRL_ATTR_HDRSIZE, family->hdrsize) ||
1241 nla_put_u32(skb, CTRL_ATTR_MAXATTR, family->maxattr))
1242 goto nla_put_failure;
1244 if (genl_op_iter_init(family, &i)) {
1245 struct nlattr *nla_ops;
1247 nla_ops = nla_nest_start_noflag(skb, CTRL_ATTR_OPS);
1248 if (nla_ops == NULL)
1249 goto nla_put_failure;
1251 while (genl_op_iter_next(&i)) {
1252 struct nlattr *nest;
1256 if (i.doit.policy || i.dumpit.policy)
1257 op_flags |= GENL_CMD_CAP_HASPOL;
1259 nest = nla_nest_start_noflag(skb, genl_op_iter_idx(&i));
1261 goto nla_put_failure;
1263 if (nla_put_u32(skb, CTRL_ATTR_OP_ID, i.cmd) ||
1264 nla_put_u32(skb, CTRL_ATTR_OP_FLAGS, op_flags))
1265 goto nla_put_failure;
1267 nla_nest_end(skb, nest);
1270 nla_nest_end(skb, nla_ops);
1273 if (family->n_mcgrps) {
1274 struct nlattr *nla_grps;
1277 nla_grps = nla_nest_start_noflag(skb, CTRL_ATTR_MCAST_GROUPS);
1278 if (nla_grps == NULL)
1279 goto nla_put_failure;
1281 for (i = 0; i < family->n_mcgrps; i++) {
1282 struct nlattr *nest;
1283 const struct genl_multicast_group *grp;
1285 grp = &family->mcgrps[i];
1287 nest = nla_nest_start_noflag(skb, i + 1);
1289 goto nla_put_failure;
1291 if (nla_put_u32(skb, CTRL_ATTR_MCAST_GRP_ID,
1292 family->mcgrp_offset + i) ||
1293 nla_put_string(skb, CTRL_ATTR_MCAST_GRP_NAME,
1295 goto nla_put_failure;
1297 nla_nest_end(skb, nest);
1299 nla_nest_end(skb, nla_grps);
1302 genlmsg_end(skb, hdr);
1306 genlmsg_cancel(skb, hdr);
1310 static int ctrl_fill_mcgrp_info(const struct genl_family *family,
1311 const struct genl_multicast_group *grp,
1312 int grp_id, u32 portid, u32 seq, u32 flags,
1313 struct sk_buff *skb, u8 cmd)
1316 struct nlattr *nla_grps;
1317 struct nlattr *nest;
1319 hdr = genlmsg_put(skb, portid, seq, &genl_ctrl, flags, cmd);
1323 if (nla_put_string(skb, CTRL_ATTR_FAMILY_NAME, family->name) ||
1324 nla_put_u16(skb, CTRL_ATTR_FAMILY_ID, family->id))
1325 goto nla_put_failure;
1327 nla_grps = nla_nest_start_noflag(skb, CTRL_ATTR_MCAST_GROUPS);
1328 if (nla_grps == NULL)
1329 goto nla_put_failure;
1331 nest = nla_nest_start_noflag(skb, 1);
1333 goto nla_put_failure;
1335 if (nla_put_u32(skb, CTRL_ATTR_MCAST_GRP_ID, grp_id) ||
1336 nla_put_string(skb, CTRL_ATTR_MCAST_GRP_NAME,
1338 goto nla_put_failure;
1340 nla_nest_end(skb, nest);
1341 nla_nest_end(skb, nla_grps);
1343 genlmsg_end(skb, hdr);
1347 genlmsg_cancel(skb, hdr);
1351 static int ctrl_dumpfamily(struct sk_buff *skb, struct netlink_callback *cb)
1354 struct genl_family *rt;
1355 struct net *net = sock_net(skb->sk);
1356 int fams_to_skip = cb->args[0];
1359 idr_for_each_entry(&genl_fam_idr, rt, id) {
1360 if (!rt->netnsok && !net_eq(net, &init_net))
1363 if (n++ < fams_to_skip)
1366 if (ctrl_fill_info(rt, NETLINK_CB(cb->skb).portid,
1367 cb->nlh->nlmsg_seq, NLM_F_MULTI,
1368 skb, CTRL_CMD_NEWFAMILY) < 0) {
1378 static struct sk_buff *ctrl_build_family_msg(const struct genl_family *family,
1379 u32 portid, int seq, u8 cmd)
1381 struct sk_buff *skb;
1384 skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
1386 return ERR_PTR(-ENOBUFS);
1388 err = ctrl_fill_info(family, portid, seq, 0, skb, cmd);
1391 return ERR_PTR(err);
1397 static struct sk_buff *
1398 ctrl_build_mcgrp_msg(const struct genl_family *family,
1399 const struct genl_multicast_group *grp,
1400 int grp_id, u32 portid, int seq, u8 cmd)
1402 struct sk_buff *skb;
1405 skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
1407 return ERR_PTR(-ENOBUFS);
1409 err = ctrl_fill_mcgrp_info(family, grp, grp_id, portid,
1413 return ERR_PTR(err);
1419 static const struct nla_policy ctrl_policy_family[] = {
1420 [CTRL_ATTR_FAMILY_ID] = { .type = NLA_U16 },
1421 [CTRL_ATTR_FAMILY_NAME] = { .type = NLA_NUL_STRING,
1422 .len = GENL_NAMSIZ - 1 },
1425 static int ctrl_getfamily(struct sk_buff *skb, struct genl_info *info)
1427 struct sk_buff *msg;
1428 const struct genl_family *res = NULL;
1431 if (info->attrs[CTRL_ATTR_FAMILY_ID]) {
1432 u16 id = nla_get_u16(info->attrs[CTRL_ATTR_FAMILY_ID]);
1433 res = genl_family_find_byid(id);
1437 if (info->attrs[CTRL_ATTR_FAMILY_NAME]) {
1440 name = nla_data(info->attrs[CTRL_ATTR_FAMILY_NAME]);
1441 res = genl_family_find_byname(name);
1442 #ifdef CONFIG_MODULES
1446 request_module("net-pf-%d-proto-%d-family-%s",
1447 PF_NETLINK, NETLINK_GENERIC, name);
1448 down_read(&cb_lock);
1450 res = genl_family_find_byname(name);
1459 if (!res->netnsok && !net_eq(genl_info_net(info), &init_net)) {
1460 /* family doesn't exist here */
1464 msg = ctrl_build_family_msg(res, info->snd_portid, info->snd_seq,
1465 CTRL_CMD_NEWFAMILY);
1467 return PTR_ERR(msg);
1469 return genlmsg_reply(msg, info);
1472 static int genl_ctrl_event(int event, const struct genl_family *family,
1473 const struct genl_multicast_group *grp,
1476 struct sk_buff *msg;
1478 /* genl is still initialising */
1479 if (!init_net.genl_sock)
1483 case CTRL_CMD_NEWFAMILY:
1484 case CTRL_CMD_DELFAMILY:
1486 msg = ctrl_build_family_msg(family, 0, 0, event);
1488 case CTRL_CMD_NEWMCAST_GRP:
1489 case CTRL_CMD_DELMCAST_GRP:
1491 msg = ctrl_build_mcgrp_msg(family, grp, grp_id, 0, 0, event);
1498 return PTR_ERR(msg);
1500 if (!family->netnsok) {
1501 genlmsg_multicast_netns(&genl_ctrl, &init_net, msg, 0,
1505 genlmsg_multicast_allns(&genl_ctrl, msg, 0,
1513 struct ctrl_dump_policy_ctx {
1514 struct netlink_policy_dump_state *state;
1515 const struct genl_family *rt;
1516 struct genl_op_iter *op_iter;
1523 static const struct nla_policy ctrl_policy_policy[] = {
1524 [CTRL_ATTR_FAMILY_ID] = { .type = NLA_U16 },
1525 [CTRL_ATTR_FAMILY_NAME] = { .type = NLA_NUL_STRING,
1526 .len = GENL_NAMSIZ - 1 },
1527 [CTRL_ATTR_OP] = { .type = NLA_U32 },
1530 static int ctrl_dumppolicy_start(struct netlink_callback *cb)
1532 const struct genl_dumpit_info *info = genl_dumpit_info(cb);
1533 struct ctrl_dump_policy_ctx *ctx = (void *)cb->ctx;
1534 struct nlattr **tb = info->info.attrs;
1535 const struct genl_family *rt;
1536 struct genl_op_iter i;
1539 BUILD_BUG_ON(sizeof(*ctx) > sizeof(cb->ctx));
1541 if (!tb[CTRL_ATTR_FAMILY_ID] && !tb[CTRL_ATTR_FAMILY_NAME])
1544 if (tb[CTRL_ATTR_FAMILY_ID]) {
1545 ctx->fam_id = nla_get_u16(tb[CTRL_ATTR_FAMILY_ID]);
1547 rt = genl_family_find_byname(
1548 nla_data(tb[CTRL_ATTR_FAMILY_NAME]));
1551 ctx->fam_id = rt->id;
1554 rt = genl_family_find_byid(ctx->fam_id);
1560 if (tb[CTRL_ATTR_OP]) {
1561 struct genl_split_ops doit, dump;
1563 ctx->single_op = true;
1564 ctx->op = nla_get_u32(tb[CTRL_ATTR_OP]);
1566 err = genl_get_cmd_both(ctx->op, rt, &doit, &dump);
1568 NL_SET_BAD_ATTR(cb->extack, tb[CTRL_ATTR_OP]);
1573 err = netlink_policy_dump_add_policy(&ctx->state,
1577 goto err_free_state;
1580 err = netlink_policy_dump_add_policy(&ctx->state,
1584 goto err_free_state;
1594 ctx->op_iter = kmalloc(sizeof(*ctx->op_iter), GFP_KERNEL);
1598 genl_op_iter_init(rt, ctx->op_iter);
1599 ctx->dump_map = genl_op_iter_next(ctx->op_iter);
1601 for (genl_op_iter_init(rt, &i); genl_op_iter_next(&i); ) {
1602 if (i.doit.policy) {
1603 err = netlink_policy_dump_add_policy(&ctx->state,
1607 goto err_free_state;
1609 if (i.dumpit.policy) {
1610 err = netlink_policy_dump_add_policy(&ctx->state,
1614 goto err_free_state;
1620 goto err_free_op_iter;
1625 netlink_policy_dump_free(ctx->state);
1627 kfree(ctx->op_iter);
1631 static void *ctrl_dumppolicy_prep(struct sk_buff *skb,
1632 struct netlink_callback *cb)
1634 struct ctrl_dump_policy_ctx *ctx = (void *)cb->ctx;
1637 hdr = genlmsg_put(skb, NETLINK_CB(cb->skb).portid,
1638 cb->nlh->nlmsg_seq, &genl_ctrl,
1639 NLM_F_MULTI, CTRL_CMD_GETPOLICY);
1643 if (nla_put_u16(skb, CTRL_ATTR_FAMILY_ID, ctx->fam_id))
1649 static int ctrl_dumppolicy_put_op(struct sk_buff *skb,
1650 struct netlink_callback *cb,
1651 struct genl_split_ops *doit,
1652 struct genl_split_ops *dumpit)
1654 struct ctrl_dump_policy_ctx *ctx = (void *)cb->ctx;
1655 struct nlattr *nest_pol, *nest_op;
1659 /* skip if we have nothing to show */
1660 if (!doit->policy && !dumpit->policy)
1663 hdr = ctrl_dumppolicy_prep(skb, cb);
1667 nest_pol = nla_nest_start(skb, CTRL_ATTR_OP_POLICY);
1671 nest_op = nla_nest_start(skb, doit->cmd);
1676 idx = netlink_policy_dump_get_policy_idx(ctx->state,
1680 if (nla_put_u32(skb, CTRL_ATTR_POLICY_DO, idx))
1683 if (dumpit->policy) {
1684 idx = netlink_policy_dump_get_policy_idx(ctx->state,
1688 if (nla_put_u32(skb, CTRL_ATTR_POLICY_DUMP, idx))
1692 nla_nest_end(skb, nest_op);
1693 nla_nest_end(skb, nest_pol);
1694 genlmsg_end(skb, hdr);
1698 genlmsg_cancel(skb, hdr);
1702 static int ctrl_dumppolicy(struct sk_buff *skb, struct netlink_callback *cb)
1704 struct ctrl_dump_policy_ctx *ctx = (void *)cb->ctx;
1707 if (ctx->dump_map) {
1708 if (ctx->single_op) {
1709 struct genl_split_ops doit, dumpit;
1711 if (WARN_ON(genl_get_cmd_both(ctx->op, ctx->rt,
1715 if (ctrl_dumppolicy_put_op(skb, cb, &doit, &dumpit))
1718 /* done with the per-op policy index list */
1722 while (ctx->dump_map) {
1723 if (ctrl_dumppolicy_put_op(skb, cb,
1724 &ctx->op_iter->doit,
1725 &ctx->op_iter->dumpit))
1728 ctx->dump_map = genl_op_iter_next(ctx->op_iter);
1732 while (netlink_policy_dump_loop(ctx->state)) {
1733 struct nlattr *nest;
1735 hdr = ctrl_dumppolicy_prep(skb, cb);
1737 goto nla_put_failure;
1739 nest = nla_nest_start(skb, CTRL_ATTR_POLICY);
1741 goto nla_put_failure;
1743 if (netlink_policy_dump_write(skb, ctx->state))
1744 goto nla_put_failure;
1746 nla_nest_end(skb, nest);
1748 genlmsg_end(skb, hdr);
1754 genlmsg_cancel(skb, hdr);
1758 static int ctrl_dumppolicy_done(struct netlink_callback *cb)
1760 struct ctrl_dump_policy_ctx *ctx = (void *)cb->ctx;
1762 kfree(ctx->op_iter);
1763 netlink_policy_dump_free(ctx->state);
1767 static const struct genl_split_ops genl_ctrl_ops[] = {
1769 .cmd = CTRL_CMD_GETFAMILY,
1770 .validate = GENL_DONT_VALIDATE_STRICT,
1771 .policy = ctrl_policy_family,
1772 .maxattr = ARRAY_SIZE(ctrl_policy_family) - 1,
1773 .doit = ctrl_getfamily,
1774 .flags = GENL_CMD_CAP_DO,
1777 .cmd = CTRL_CMD_GETFAMILY,
1778 .validate = GENL_DONT_VALIDATE_DUMP,
1779 .policy = ctrl_policy_family,
1780 .maxattr = ARRAY_SIZE(ctrl_policy_family) - 1,
1781 .dumpit = ctrl_dumpfamily,
1782 .flags = GENL_CMD_CAP_DUMP,
1785 .cmd = CTRL_CMD_GETPOLICY,
1786 .policy = ctrl_policy_policy,
1787 .maxattr = ARRAY_SIZE(ctrl_policy_policy) - 1,
1788 .start = ctrl_dumppolicy_start,
1789 .dumpit = ctrl_dumppolicy,
1790 .done = ctrl_dumppolicy_done,
1791 .flags = GENL_CMD_CAP_DUMP,
1795 static const struct genl_multicast_group genl_ctrl_groups[] = {
1796 { .name = "notify", },
1799 static struct genl_family genl_ctrl __ro_after_init = {
1800 .module = THIS_MODULE,
1801 .split_ops = genl_ctrl_ops,
1802 .n_split_ops = ARRAY_SIZE(genl_ctrl_ops),
1803 .resv_start_op = CTRL_CMD_GETPOLICY + 1,
1804 .mcgrps = genl_ctrl_groups,
1805 .n_mcgrps = ARRAY_SIZE(genl_ctrl_groups),
1812 static int genl_bind(struct net *net, int group)
1814 const struct genl_family *family;
1818 down_read(&cb_lock);
1820 idr_for_each_entry(&genl_fam_idr, family, id) {
1821 const struct genl_multicast_group *grp;
1824 if (family->n_mcgrps == 0)
1827 i = group - family->mcgrp_offset;
1828 if (i < 0 || i >= family->n_mcgrps)
1831 grp = &family->mcgrps[i];
1832 if ((grp->flags & GENL_MCAST_CAP_NET_ADMIN) &&
1833 !ns_capable(net->user_ns, CAP_NET_ADMIN))
1835 if ((grp->flags & GENL_MCAST_CAP_SYS_ADMIN) &&
1836 !ns_capable(net->user_ns, CAP_SYS_ADMIN))
1846 static int __net_init genl_pernet_init(struct net *net)
1848 struct netlink_kernel_cfg cfg = {
1850 .flags = NL_CFG_F_NONROOT_RECV,
1852 .release = genl_release,
1855 /* we'll bump the group number right afterwards */
1856 net->genl_sock = netlink_kernel_create(net, NETLINK_GENERIC, &cfg);
1858 if (!net->genl_sock && net_eq(net, &init_net))
1859 panic("GENL: Cannot initialize generic netlink\n");
1861 if (!net->genl_sock)
1867 static void __net_exit genl_pernet_exit(struct net *net)
1869 netlink_kernel_release(net->genl_sock);
1870 net->genl_sock = NULL;
1873 static struct pernet_operations genl_pernet_ops = {
1874 .init = genl_pernet_init,
1875 .exit = genl_pernet_exit,
1878 static int __init genl_init(void)
1882 err = genl_register_family(&genl_ctrl);
1886 err = register_pernet_subsys(&genl_pernet_ops);
1893 panic("GENL: Cannot register controller: %d\n", err);
1896 core_initcall(genl_init);
1898 static int genlmsg_mcast(struct sk_buff *skb, u32 portid, unsigned long group,
1901 struct sk_buff *tmp;
1902 struct net *net, *prev = NULL;
1903 bool delivered = false;
1906 for_each_net_rcu(net) {
1908 tmp = skb_clone(skb, flags);
1913 err = nlmsg_multicast(prev->genl_sock, tmp,
1914 portid, group, flags);
1917 else if (err != -ESRCH)
1924 err = nlmsg_multicast(prev->genl_sock, skb, portid, group, flags);
1927 else if (err != -ESRCH)
1929 return delivered ? 0 : -ESRCH;
1935 int genlmsg_multicast_allns(const struct genl_family *family,
1936 struct sk_buff *skb, u32 portid,
1937 unsigned int group, gfp_t flags)
1939 if (WARN_ON_ONCE(group >= family->n_mcgrps))
1942 group = family->mcgrp_offset + group;
1943 return genlmsg_mcast(skb, portid, group, flags);
1945 EXPORT_SYMBOL(genlmsg_multicast_allns);
1947 void genl_notify(const struct genl_family *family, struct sk_buff *skb,
1948 struct genl_info *info, u32 group, gfp_t flags)
1950 struct net *net = genl_info_net(info);
1951 struct sock *sk = net->genl_sock;
1953 if (WARN_ON_ONCE(group >= family->n_mcgrps))
1956 group = family->mcgrp_offset + group;
1957 nlmsg_notify(sk, skb, info->snd_portid, group,
1958 nlmsg_report(info->nlhdr), flags);
1960 EXPORT_SYMBOL(genl_notify);