2 * x_tables core - Backend for {ip,ip6,arp}_tables
4 * Copyright (C) 2006-2006 Harald Welte <laforge@netfilter.org>
5 * Copyright (C) 2006-2012 Patrick McHardy <kaber@trash.net>
7 * Based on existing ip_tables code which is
8 * Copyright (C) 1999 Paul `Rusty' Russell & Michael J. Neuling
9 * Copyright (C) 2000-2005 Netfilter Core Team <coreteam@netfilter.org>
11 * This program is free software; you can redistribute it and/or modify
12 * it under the terms of the GNU General Public License version 2 as
13 * published by the Free Software Foundation.
16 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
17 #include <linux/kernel.h>
18 #include <linux/module.h>
19 #include <linux/socket.h>
20 #include <linux/net.h>
21 #include <linux/proc_fs.h>
22 #include <linux/seq_file.h>
23 #include <linux/string.h>
24 #include <linux/vmalloc.h>
25 #include <linux/mutex.h>
27 #include <linux/slab.h>
28 #include <linux/audit.h>
29 #include <linux/user_namespace.h>
30 #include <net/net_namespace.h>
32 #include <linux/netfilter/x_tables.h>
33 #include <linux/netfilter_arp.h>
34 #include <linux/netfilter_ipv4/ip_tables.h>
35 #include <linux/netfilter_ipv6/ip6_tables.h>
36 #include <linux/netfilter_arp/arp_tables.h>
38 MODULE_LICENSE("GPL");
39 MODULE_AUTHOR("Harald Welte <laforge@netfilter.org>");
40 MODULE_DESCRIPTION("{ip,ip6,arp,eb}_tables backend module");
42 #define SMP_ALIGN(x) (((x) + SMP_CACHE_BYTES-1) & ~(SMP_CACHE_BYTES-1))
43 #define XT_PCPU_BLOCK_SIZE 4096
46 unsigned int offset; /* offset in kernel */
47 int delta; /* delta in 32bit user land */
52 struct list_head match;
53 struct list_head target;
55 struct mutex compat_mutex;
56 struct compat_delta *compat_tab;
57 unsigned int number; /* number of slots in compat_tab[] */
58 unsigned int cur; /* number of used slots in compat_tab[] */
62 static struct xt_af *xt;
64 static const char *const xt_prefix[NFPROTO_NUMPROTO] = {
65 [NFPROTO_UNSPEC] = "x",
66 [NFPROTO_IPV4] = "ip",
67 [NFPROTO_ARP] = "arp",
68 [NFPROTO_BRIDGE] = "eb",
69 [NFPROTO_IPV6] = "ip6",
72 /* Registration hooks for targets. */
73 int xt_register_target(struct xt_target *target)
75 u_int8_t af = target->family;
77 mutex_lock(&xt[af].mutex);
78 list_add(&target->list, &xt[af].target);
79 mutex_unlock(&xt[af].mutex);
82 EXPORT_SYMBOL(xt_register_target);
85 xt_unregister_target(struct xt_target *target)
87 u_int8_t af = target->family;
89 mutex_lock(&xt[af].mutex);
90 list_del(&target->list);
91 mutex_unlock(&xt[af].mutex);
93 EXPORT_SYMBOL(xt_unregister_target);
96 xt_register_targets(struct xt_target *target, unsigned int n)
101 for (i = 0; i < n; i++) {
102 err = xt_register_target(&target[i]);
110 xt_unregister_targets(target, i);
113 EXPORT_SYMBOL(xt_register_targets);
116 xt_unregister_targets(struct xt_target *target, unsigned int n)
119 xt_unregister_target(&target[n]);
121 EXPORT_SYMBOL(xt_unregister_targets);
123 int xt_register_match(struct xt_match *match)
125 u_int8_t af = match->family;
127 mutex_lock(&xt[af].mutex);
128 list_add(&match->list, &xt[af].match);
129 mutex_unlock(&xt[af].mutex);
132 EXPORT_SYMBOL(xt_register_match);
135 xt_unregister_match(struct xt_match *match)
137 u_int8_t af = match->family;
139 mutex_lock(&xt[af].mutex);
140 list_del(&match->list);
141 mutex_unlock(&xt[af].mutex);
143 EXPORT_SYMBOL(xt_unregister_match);
146 xt_register_matches(struct xt_match *match, unsigned int n)
151 for (i = 0; i < n; i++) {
152 err = xt_register_match(&match[i]);
160 xt_unregister_matches(match, i);
163 EXPORT_SYMBOL(xt_register_matches);
166 xt_unregister_matches(struct xt_match *match, unsigned int n)
169 xt_unregister_match(&match[n]);
171 EXPORT_SYMBOL(xt_unregister_matches);
175 * These are weird, but module loading must not be done with mutex
176 * held (since they will register), and we have to have a single
180 /* Find match, grabs ref. Returns ERR_PTR() on error. */
181 struct xt_match *xt_find_match(u8 af, const char *name, u8 revision)
186 mutex_lock(&xt[af].mutex);
187 list_for_each_entry(m, &xt[af].match, list) {
188 if (strcmp(m->name, name) == 0) {
189 if (m->revision == revision) {
190 if (try_module_get(m->me)) {
191 mutex_unlock(&xt[af].mutex);
195 err = -EPROTOTYPE; /* Found something. */
198 mutex_unlock(&xt[af].mutex);
200 if (af != NFPROTO_UNSPEC)
201 /* Try searching again in the family-independent list */
202 return xt_find_match(NFPROTO_UNSPEC, name, revision);
206 EXPORT_SYMBOL(xt_find_match);
209 xt_request_find_match(uint8_t nfproto, const char *name, uint8_t revision)
211 struct xt_match *match;
213 match = xt_find_match(nfproto, name, revision);
215 request_module("%st_%s", xt_prefix[nfproto], name);
216 match = xt_find_match(nfproto, name, revision);
221 EXPORT_SYMBOL_GPL(xt_request_find_match);
223 /* Find target, grabs ref. Returns ERR_PTR() on error. */
224 struct xt_target *xt_find_target(u8 af, const char *name, u8 revision)
229 mutex_lock(&xt[af].mutex);
230 list_for_each_entry(t, &xt[af].target, list) {
231 if (strcmp(t->name, name) == 0) {
232 if (t->revision == revision) {
233 if (try_module_get(t->me)) {
234 mutex_unlock(&xt[af].mutex);
238 err = -EPROTOTYPE; /* Found something. */
241 mutex_unlock(&xt[af].mutex);
243 if (af != NFPROTO_UNSPEC)
244 /* Try searching again in the family-independent list */
245 return xt_find_target(NFPROTO_UNSPEC, name, revision);
249 EXPORT_SYMBOL(xt_find_target);
251 struct xt_target *xt_request_find_target(u8 af, const char *name, u8 revision)
253 struct xt_target *target;
255 target = xt_find_target(af, name, revision);
256 if (IS_ERR(target)) {
257 request_module("%st_%s", xt_prefix[af], name);
258 target = xt_find_target(af, name, revision);
263 EXPORT_SYMBOL_GPL(xt_request_find_target);
266 static int xt_obj_to_user(u16 __user *psize, u16 size,
267 void __user *pname, const char *name,
268 u8 __user *prev, u8 rev)
270 if (put_user(size, psize))
272 if (copy_to_user(pname, name, strlen(name) + 1))
274 if (put_user(rev, prev))
280 #define XT_OBJ_TO_USER(U, K, TYPE, C_SIZE) \
281 xt_obj_to_user(&U->u.TYPE##_size, C_SIZE ? : K->u.TYPE##_size, \
282 U->u.user.name, K->u.kernel.TYPE->name, \
283 &U->u.user.revision, K->u.kernel.TYPE->revision)
285 int xt_data_to_user(void __user *dst, const void *src,
286 int usersize, int size, int aligned_size)
288 usersize = usersize ? : size;
289 if (copy_to_user(dst, src, usersize))
291 if (usersize != aligned_size &&
292 clear_user(dst + usersize, aligned_size - usersize))
297 EXPORT_SYMBOL_GPL(xt_data_to_user);
299 #define XT_DATA_TO_USER(U, K, TYPE) \
300 xt_data_to_user(U->data, K->data, \
301 K->u.kernel.TYPE->usersize, \
302 K->u.kernel.TYPE->TYPE##size, \
303 XT_ALIGN(K->u.kernel.TYPE->TYPE##size))
305 int xt_match_to_user(const struct xt_entry_match *m,
306 struct xt_entry_match __user *u)
308 return XT_OBJ_TO_USER(u, m, match, 0) ||
309 XT_DATA_TO_USER(u, m, match);
311 EXPORT_SYMBOL_GPL(xt_match_to_user);
313 int xt_target_to_user(const struct xt_entry_target *t,
314 struct xt_entry_target __user *u)
316 return XT_OBJ_TO_USER(u, t, target, 0) ||
317 XT_DATA_TO_USER(u, t, target);
319 EXPORT_SYMBOL_GPL(xt_target_to_user);
321 static int match_revfn(u8 af, const char *name, u8 revision, int *bestp)
323 const struct xt_match *m;
326 list_for_each_entry(m, &xt[af].match, list) {
327 if (strcmp(m->name, name) == 0) {
328 if (m->revision > *bestp)
329 *bestp = m->revision;
330 if (m->revision == revision)
335 if (af != NFPROTO_UNSPEC && !have_rev)
336 return match_revfn(NFPROTO_UNSPEC, name, revision, bestp);
341 static int target_revfn(u8 af, const char *name, u8 revision, int *bestp)
343 const struct xt_target *t;
346 list_for_each_entry(t, &xt[af].target, list) {
347 if (strcmp(t->name, name) == 0) {
348 if (t->revision > *bestp)
349 *bestp = t->revision;
350 if (t->revision == revision)
355 if (af != NFPROTO_UNSPEC && !have_rev)
356 return target_revfn(NFPROTO_UNSPEC, name, revision, bestp);
361 /* Returns true or false (if no such extension at all) */
362 int xt_find_revision(u8 af, const char *name, u8 revision, int target,
365 int have_rev, best = -1;
367 mutex_lock(&xt[af].mutex);
369 have_rev = target_revfn(af, name, revision, &best);
371 have_rev = match_revfn(af, name, revision, &best);
372 mutex_unlock(&xt[af].mutex);
374 /* Nothing at all? Return 0 to try loading module. */
382 *err = -EPROTONOSUPPORT;
385 EXPORT_SYMBOL_GPL(xt_find_revision);
388 textify_hooks(char *buf, size_t size, unsigned int mask, uint8_t nfproto)
390 static const char *const inetbr_names[] = {
391 "PREROUTING", "INPUT", "FORWARD",
392 "OUTPUT", "POSTROUTING", "BROUTING",
394 static const char *const arp_names[] = {
395 "INPUT", "FORWARD", "OUTPUT",
397 const char *const *names;
403 names = (nfproto == NFPROTO_ARP) ? arp_names : inetbr_names;
404 max = (nfproto == NFPROTO_ARP) ? ARRAY_SIZE(arp_names) :
405 ARRAY_SIZE(inetbr_names);
407 for (i = 0; i < max; ++i) {
408 if (!(mask & (1 << i)))
410 res = snprintf(p, size, "%s%s", np ? "/" : "", names[i]);
421 int xt_check_match(struct xt_mtchk_param *par,
422 unsigned int size, u_int8_t proto, bool inv_proto)
426 if (XT_ALIGN(par->match->matchsize) != size &&
427 par->match->matchsize != -1) {
429 * ebt_among is exempt from centralized matchsize checking
430 * because it uses a dynamic-size data set.
432 pr_err("%s_tables: %s.%u match: invalid size "
433 "%u (kernel) != (user) %u\n",
434 xt_prefix[par->family], par->match->name,
435 par->match->revision,
436 XT_ALIGN(par->match->matchsize), size);
439 if (par->match->table != NULL &&
440 strcmp(par->match->table, par->table) != 0) {
441 pr_err("%s_tables: %s match: only valid in %s table, not %s\n",
442 xt_prefix[par->family], par->match->name,
443 par->match->table, par->table);
446 if (par->match->hooks && (par->hook_mask & ~par->match->hooks) != 0) {
447 char used[64], allow[64];
449 pr_err("%s_tables: %s match: used from hooks %s, but only "
451 xt_prefix[par->family], par->match->name,
452 textify_hooks(used, sizeof(used), par->hook_mask,
454 textify_hooks(allow, sizeof(allow), par->match->hooks,
458 if (par->match->proto && (par->match->proto != proto || inv_proto)) {
459 pr_err("%s_tables: %s match: only valid for protocol %u\n",
460 xt_prefix[par->family], par->match->name,
464 if (par->match->checkentry != NULL) {
465 ret = par->match->checkentry(par);
469 /* Flag up potential errors. */
474 EXPORT_SYMBOL_GPL(xt_check_match);
476 /** xt_check_entry_match - check that matches end before start of target
478 * @match: beginning of xt_entry_match
479 * @target: beginning of this rules target (alleged end of matches)
480 * @alignment: alignment requirement of match structures
482 * Validates that all matches add up to the beginning of the target,
483 * and that each match covers at least the base structure size.
485 * Return: 0 on success, negative errno on failure.
487 static int xt_check_entry_match(const char *match, const char *target,
488 const size_t alignment)
490 const struct xt_entry_match *pos;
491 int length = target - match;
493 if (length == 0) /* no matches */
496 pos = (struct xt_entry_match *)match;
498 if ((unsigned long)pos % alignment)
501 if (length < (int)sizeof(struct xt_entry_match))
504 if (pos->u.match_size < sizeof(struct xt_entry_match))
507 if (pos->u.match_size > length)
510 length -= pos->u.match_size;
511 pos = ((void *)((char *)(pos) + (pos)->u.match_size));
512 } while (length > 0);
518 int xt_compat_add_offset(u_int8_t af, unsigned int offset, int delta)
520 struct xt_af *xp = &xt[af];
522 if (!xp->compat_tab) {
525 xp->compat_tab = vmalloc(sizeof(struct compat_delta) * xp->number);
531 if (xp->cur >= xp->number)
535 delta += xp->compat_tab[xp->cur - 1].delta;
536 xp->compat_tab[xp->cur].offset = offset;
537 xp->compat_tab[xp->cur].delta = delta;
541 EXPORT_SYMBOL_GPL(xt_compat_add_offset);
543 void xt_compat_flush_offsets(u_int8_t af)
545 if (xt[af].compat_tab) {
546 vfree(xt[af].compat_tab);
547 xt[af].compat_tab = NULL;
552 EXPORT_SYMBOL_GPL(xt_compat_flush_offsets);
554 int xt_compat_calc_jump(u_int8_t af, unsigned int offset)
556 struct compat_delta *tmp = xt[af].compat_tab;
557 int mid, left = 0, right = xt[af].cur - 1;
559 while (left <= right) {
560 mid = (left + right) >> 1;
561 if (offset > tmp[mid].offset)
563 else if (offset < tmp[mid].offset)
566 return mid ? tmp[mid - 1].delta : 0;
568 return left ? tmp[left - 1].delta : 0;
570 EXPORT_SYMBOL_GPL(xt_compat_calc_jump);
572 void xt_compat_init_offsets(u_int8_t af, unsigned int number)
574 xt[af].number = number;
577 EXPORT_SYMBOL(xt_compat_init_offsets);
579 int xt_compat_match_offset(const struct xt_match *match)
581 u_int16_t csize = match->compatsize ? : match->matchsize;
582 return XT_ALIGN(match->matchsize) - COMPAT_XT_ALIGN(csize);
584 EXPORT_SYMBOL_GPL(xt_compat_match_offset);
586 void xt_compat_match_from_user(struct xt_entry_match *m, void **dstptr,
589 const struct xt_match *match = m->u.kernel.match;
590 struct compat_xt_entry_match *cm = (struct compat_xt_entry_match *)m;
591 int pad, off = xt_compat_match_offset(match);
592 u_int16_t msize = cm->u.user.match_size;
593 char name[sizeof(m->u.user.name)];
596 memcpy(m, cm, sizeof(*cm));
597 if (match->compat_from_user)
598 match->compat_from_user(m->data, cm->data);
600 memcpy(m->data, cm->data, msize - sizeof(*cm));
601 pad = XT_ALIGN(match->matchsize) - match->matchsize;
603 memset(m->data + match->matchsize, 0, pad);
606 m->u.user.match_size = msize;
607 strlcpy(name, match->name, sizeof(name));
608 module_put(match->me);
609 strncpy(m->u.user.name, name, sizeof(m->u.user.name));
614 EXPORT_SYMBOL_GPL(xt_compat_match_from_user);
616 #define COMPAT_XT_DATA_TO_USER(U, K, TYPE, C_SIZE) \
617 xt_data_to_user(U->data, K->data, \
618 K->u.kernel.TYPE->usersize, \
620 COMPAT_XT_ALIGN(C_SIZE))
622 int xt_compat_match_to_user(const struct xt_entry_match *m,
623 void __user **dstptr, unsigned int *size)
625 const struct xt_match *match = m->u.kernel.match;
626 struct compat_xt_entry_match __user *cm = *dstptr;
627 int off = xt_compat_match_offset(match);
628 u_int16_t msize = m->u.user.match_size - off;
630 if (XT_OBJ_TO_USER(cm, m, match, msize))
633 if (match->compat_to_user) {
634 if (match->compat_to_user((void __user *)cm->data, m->data))
637 if (COMPAT_XT_DATA_TO_USER(cm, m, match, msize - sizeof(*cm)))
645 EXPORT_SYMBOL_GPL(xt_compat_match_to_user);
647 /* non-compat version may have padding after verdict */
648 struct compat_xt_standard_target {
649 struct compat_xt_entry_target t;
650 compat_uint_t verdict;
653 int xt_compat_check_entry_offsets(const void *base, const char *elems,
654 unsigned int target_offset,
655 unsigned int next_offset)
657 long size_of_base_struct = elems - (const char *)base;
658 const struct compat_xt_entry_target *t;
659 const char *e = base;
661 if (target_offset < size_of_base_struct)
664 if (target_offset + sizeof(*t) > next_offset)
667 t = (void *)(e + target_offset);
668 if (t->u.target_size < sizeof(*t))
671 if (target_offset + t->u.target_size > next_offset)
674 if (strcmp(t->u.user.name, XT_STANDARD_TARGET) == 0 &&
675 COMPAT_XT_ALIGN(target_offset + sizeof(struct compat_xt_standard_target)) != next_offset)
678 /* compat_xt_entry match has less strict alignment requirements,
679 * otherwise they are identical. In case of padding differences
680 * we need to add compat version of xt_check_entry_match.
682 BUILD_BUG_ON(sizeof(struct compat_xt_entry_match) != sizeof(struct xt_entry_match));
684 return xt_check_entry_match(elems, base + target_offset,
685 __alignof__(struct compat_xt_entry_match));
687 EXPORT_SYMBOL(xt_compat_check_entry_offsets);
688 #endif /* CONFIG_COMPAT */
691 * xt_check_entry_offsets - validate arp/ip/ip6t_entry
693 * @base: pointer to arp/ip/ip6t_entry
694 * @elems: pointer to first xt_entry_match, i.e. ip(6)t_entry->elems
695 * @target_offset: the arp/ip/ip6_t->target_offset
696 * @next_offset: the arp/ip/ip6_t->next_offset
698 * validates that target_offset and next_offset are sane and that all
699 * match sizes (if any) align with the target offset.
701 * This function does not validate the targets or matches themselves, it
702 * only tests that all the offsets and sizes are correct, that all
703 * match structures are aligned, and that the last structure ends where
704 * the target structure begins.
706 * Also see xt_compat_check_entry_offsets for CONFIG_COMPAT version.
708 * The arp/ip/ip6t_entry structure @base must have passed following tests:
709 * - it must point to a valid memory location
710 * - base to base + next_offset must be accessible, i.e. not exceed allocated
713 * A well-formed entry looks like this:
715 * ip(6)t_entry match [mtdata] match [mtdata] target [tgdata] ip(6)t_entry
716 * e->elems[]-----' | |
720 * target_offset---------------------------------' |
721 * next_offset---------------------------------------------------'
723 * elems[]: flexible array member at end of ip(6)/arpt_entry struct.
724 * This is where matches (if any) and the target reside.
725 * target_offset: beginning of target.
726 * next_offset: start of the next rule; also: size of this rule.
727 * Since targets have a minimum size, target_offset + minlen <= next_offset.
729 * Every match stores its size, sum of sizes must not exceed target_offset.
731 * Return: 0 on success, negative errno on failure.
733 int xt_check_entry_offsets(const void *base,
735 unsigned int target_offset,
736 unsigned int next_offset)
738 long size_of_base_struct = elems - (const char *)base;
739 const struct xt_entry_target *t;
740 const char *e = base;
742 /* target start is within the ip/ip6/arpt_entry struct */
743 if (target_offset < size_of_base_struct)
746 if (target_offset + sizeof(*t) > next_offset)
749 t = (void *)(e + target_offset);
750 if (t->u.target_size < sizeof(*t))
753 if (target_offset + t->u.target_size > next_offset)
756 if (strcmp(t->u.user.name, XT_STANDARD_TARGET) == 0 &&
757 XT_ALIGN(target_offset + sizeof(struct xt_standard_target)) != next_offset)
760 return xt_check_entry_match(elems, base + target_offset,
761 __alignof__(struct xt_entry_match));
763 EXPORT_SYMBOL(xt_check_entry_offsets);
766 * xt_alloc_entry_offsets - allocate array to store rule head offsets
768 * @size: number of entries
770 * Return: NULL or kmalloc'd or vmalloc'd array
772 unsigned int *xt_alloc_entry_offsets(unsigned int size)
774 return kvmalloc_array(size, sizeof(unsigned int), GFP_KERNEL | __GFP_ZERO);
777 EXPORT_SYMBOL(xt_alloc_entry_offsets);
780 * xt_find_jump_offset - check if target is a valid jump offset
782 * @offsets: array containing all valid rule start offsets of a rule blob
783 * @target: the jump target to search for
784 * @size: entries in @offset
786 bool xt_find_jump_offset(const unsigned int *offsets,
787 unsigned int target, unsigned int size)
789 int m, low = 0, hi = size;
794 if (offsets[m] > target)
796 else if (offsets[m] < target)
804 EXPORT_SYMBOL(xt_find_jump_offset);
806 int xt_check_target(struct xt_tgchk_param *par,
807 unsigned int size, u_int8_t proto, bool inv_proto)
811 if (XT_ALIGN(par->target->targetsize) != size) {
812 pr_err("%s_tables: %s.%u target: invalid size "
813 "%u (kernel) != (user) %u\n",
814 xt_prefix[par->family], par->target->name,
815 par->target->revision,
816 XT_ALIGN(par->target->targetsize), size);
819 if (par->target->table != NULL &&
820 strcmp(par->target->table, par->table) != 0) {
821 pr_err("%s_tables: %s target: only valid in %s table, not %s\n",
822 xt_prefix[par->family], par->target->name,
823 par->target->table, par->table);
826 if (par->target->hooks && (par->hook_mask & ~par->target->hooks) != 0) {
827 char used[64], allow[64];
829 pr_err("%s_tables: %s target: used from hooks %s, but only "
831 xt_prefix[par->family], par->target->name,
832 textify_hooks(used, sizeof(used), par->hook_mask,
834 textify_hooks(allow, sizeof(allow), par->target->hooks,
838 if (par->target->proto && (par->target->proto != proto || inv_proto)) {
839 pr_err("%s_tables: %s target: only valid for protocol %u\n",
840 xt_prefix[par->family], par->target->name,
844 if (par->target->checkentry != NULL) {
845 ret = par->target->checkentry(par);
849 /* Flag up potential errors. */
854 EXPORT_SYMBOL_GPL(xt_check_target);
857 * xt_copy_counters_from_user - copy counters and metadata from userspace
859 * @user: src pointer to userspace memory
860 * @len: alleged size of userspace memory
861 * @info: where to store the xt_counters_info metadata
862 * @compat: true if we setsockopt call is done by 32bit task on 64bit kernel
864 * Copies counter meta data from @user and stores it in @info.
866 * vmallocs memory to hold the counters, then copies the counter data
867 * from @user to the new memory and returns a pointer to it.
869 * If @compat is true, @info gets converted automatically to the 64bit
872 * The metadata associated with the counters is stored in @info.
874 * Return: returns pointer that caller has to test via IS_ERR().
875 * If IS_ERR is false, caller has to vfree the pointer.
877 void *xt_copy_counters_from_user(const void __user *user, unsigned int len,
878 struct xt_counters_info *info, bool compat)
885 /* structures only differ in size due to alignment */
886 struct compat_xt_counters_info compat_tmp;
888 if (len <= sizeof(compat_tmp))
889 return ERR_PTR(-EINVAL);
891 len -= sizeof(compat_tmp);
892 if (copy_from_user(&compat_tmp, user, sizeof(compat_tmp)) != 0)
893 return ERR_PTR(-EFAULT);
895 memcpy(info->name, compat_tmp.name, sizeof(info->name) - 1);
896 info->num_counters = compat_tmp.num_counters;
897 user += sizeof(compat_tmp);
901 if (len <= sizeof(*info))
902 return ERR_PTR(-EINVAL);
904 len -= sizeof(*info);
905 if (copy_from_user(info, user, sizeof(*info)) != 0)
906 return ERR_PTR(-EFAULT);
908 user += sizeof(*info);
910 info->name[sizeof(info->name) - 1] = '\0';
912 size = sizeof(struct xt_counters);
913 size *= info->num_counters;
915 if (size != (u64)len)
916 return ERR_PTR(-EINVAL);
920 return ERR_PTR(-ENOMEM);
922 if (copy_from_user(mem, user, len) == 0)
926 return ERR_PTR(-EFAULT);
928 EXPORT_SYMBOL_GPL(xt_copy_counters_from_user);
931 int xt_compat_target_offset(const struct xt_target *target)
933 u_int16_t csize = target->compatsize ? : target->targetsize;
934 return XT_ALIGN(target->targetsize) - COMPAT_XT_ALIGN(csize);
936 EXPORT_SYMBOL_GPL(xt_compat_target_offset);
938 void xt_compat_target_from_user(struct xt_entry_target *t, void **dstptr,
941 const struct xt_target *target = t->u.kernel.target;
942 struct compat_xt_entry_target *ct = (struct compat_xt_entry_target *)t;
943 int pad, off = xt_compat_target_offset(target);
944 u_int16_t tsize = ct->u.user.target_size;
945 char name[sizeof(t->u.user.name)];
948 memcpy(t, ct, sizeof(*ct));
949 if (target->compat_from_user)
950 target->compat_from_user(t->data, ct->data);
952 memcpy(t->data, ct->data, tsize - sizeof(*ct));
953 pad = XT_ALIGN(target->targetsize) - target->targetsize;
955 memset(t->data + target->targetsize, 0, pad);
958 t->u.user.target_size = tsize;
959 strlcpy(name, target->name, sizeof(name));
960 module_put(target->me);
961 strncpy(t->u.user.name, name, sizeof(t->u.user.name));
966 EXPORT_SYMBOL_GPL(xt_compat_target_from_user);
968 int xt_compat_target_to_user(const struct xt_entry_target *t,
969 void __user **dstptr, unsigned int *size)
971 const struct xt_target *target = t->u.kernel.target;
972 struct compat_xt_entry_target __user *ct = *dstptr;
973 int off = xt_compat_target_offset(target);
974 u_int16_t tsize = t->u.user.target_size - off;
976 if (XT_OBJ_TO_USER(ct, t, target, tsize))
979 if (target->compat_to_user) {
980 if (target->compat_to_user((void __user *)ct->data, t->data))
983 if (COMPAT_XT_DATA_TO_USER(ct, t, target, tsize - sizeof(*ct)))
991 EXPORT_SYMBOL_GPL(xt_compat_target_to_user);
994 struct xt_table_info *xt_alloc_table_info(unsigned int size)
996 struct xt_table_info *info = NULL;
997 size_t sz = sizeof(*info) + size;
999 if (sz < sizeof(*info))
1002 /* Pedantry: prevent them from hitting BUG() in vmalloc.c --RR */
1003 if ((SMP_ALIGN(size) >> PAGE_SHIFT) + 2 > totalram_pages)
1006 info = kvmalloc(sz, GFP_KERNEL);
1010 memset(info, 0, sizeof(*info));
1014 EXPORT_SYMBOL(xt_alloc_table_info);
1016 void xt_free_table_info(struct xt_table_info *info)
1020 if (info->jumpstack != NULL) {
1021 for_each_possible_cpu(cpu)
1022 kvfree(info->jumpstack[cpu]);
1023 kvfree(info->jumpstack);
1028 EXPORT_SYMBOL(xt_free_table_info);
1030 /* Find table by name, grabs mutex & ref. Returns NULL on error. */
1031 struct xt_table *xt_find_table_lock(struct net *net, u_int8_t af,
1034 struct xt_table *t, *found = NULL;
1036 mutex_lock(&xt[af].mutex);
1037 list_for_each_entry(t, &net->xt.tables[af], list)
1038 if (strcmp(t->name, name) == 0 && try_module_get(t->me))
1041 if (net == &init_net)
1044 /* Table doesn't exist in this netns, re-try init */
1045 list_for_each_entry(t, &init_net.xt.tables[af], list) {
1046 if (strcmp(t->name, name))
1048 if (!try_module_get(t->me)) {
1049 mutex_unlock(&xt[af].mutex);
1053 mutex_unlock(&xt[af].mutex);
1054 if (t->table_init(net) != 0) {
1061 mutex_lock(&xt[af].mutex);
1068 /* and once again: */
1069 list_for_each_entry(t, &net->xt.tables[af], list)
1070 if (strcmp(t->name, name) == 0)
1073 module_put(found->me);
1075 mutex_unlock(&xt[af].mutex);
1078 EXPORT_SYMBOL_GPL(xt_find_table_lock);
1080 void xt_table_unlock(struct xt_table *table)
1082 mutex_unlock(&xt[table->af].mutex);
1084 EXPORT_SYMBOL_GPL(xt_table_unlock);
1086 #ifdef CONFIG_COMPAT
1087 void xt_compat_lock(u_int8_t af)
1089 mutex_lock(&xt[af].compat_mutex);
1091 EXPORT_SYMBOL_GPL(xt_compat_lock);
1093 void xt_compat_unlock(u_int8_t af)
1095 mutex_unlock(&xt[af].compat_mutex);
1097 EXPORT_SYMBOL_GPL(xt_compat_unlock);
1100 DEFINE_PER_CPU(seqcount_t, xt_recseq);
1101 EXPORT_PER_CPU_SYMBOL_GPL(xt_recseq);
1103 struct static_key xt_tee_enabled __read_mostly;
1104 EXPORT_SYMBOL_GPL(xt_tee_enabled);
1106 static int xt_jumpstack_alloc(struct xt_table_info *i)
1111 size = sizeof(void **) * nr_cpu_ids;
1112 if (size > PAGE_SIZE)
1113 i->jumpstack = kvzalloc(size, GFP_KERNEL);
1115 i->jumpstack = kzalloc(size, GFP_KERNEL);
1116 if (i->jumpstack == NULL)
1119 /* ruleset without jumps -- no stack needed */
1120 if (i->stacksize == 0)
1123 /* Jumpstack needs to be able to record two full callchains, one
1124 * from the first rule set traversal, plus one table reentrancy
1125 * via -j TEE without clobbering the callchain that brought us to
1128 * This is done by allocating two jumpstacks per cpu, on reentry
1129 * the upper half of the stack is used.
1131 * see the jumpstack setup in ipt_do_table() for more details.
1133 size = sizeof(void *) * i->stacksize * 2u;
1134 for_each_possible_cpu(cpu) {
1135 i->jumpstack[cpu] = kvmalloc_node(size, GFP_KERNEL,
1137 if (i->jumpstack[cpu] == NULL)
1139 * Freeing will be done later on by the callers. The
1140 * chain is: xt_replace_table -> __do_replace ->
1141 * do_replace -> xt_free_table_info.
1149 struct xt_table_info *
1150 xt_replace_table(struct xt_table *table,
1151 unsigned int num_counters,
1152 struct xt_table_info *newinfo,
1155 struct xt_table_info *private;
1159 ret = xt_jumpstack_alloc(newinfo);
1165 /* Do the substitution. */
1167 private = table->private;
1169 /* Check inside lock: is the old number correct? */
1170 if (num_counters != private->number) {
1171 pr_debug("num_counters != table->private->number (%u/%u)\n",
1172 num_counters, private->number);
1178 newinfo->initial_entries = private->initial_entries;
1180 * Ensure contents of newinfo are visible before assigning to
1184 table->private = newinfo;
1186 /* make sure all cpus see new ->private value */
1190 * Even though table entries have now been swapped, other CPU's
1191 * may still be using the old entries...
1195 /* ... so wait for even xt_recseq on all cpus */
1196 for_each_possible_cpu(cpu) {
1197 seqcount_t *s = &per_cpu(xt_recseq, cpu);
1198 u32 seq = raw_read_seqcount(s);
1204 } while (seq == raw_read_seqcount(s));
1209 if (audit_enabled) {
1210 audit_log(current->audit_context, GFP_KERNEL,
1211 AUDIT_NETFILTER_CFG,
1212 "table=%s family=%u entries=%u",
1213 table->name, table->af, private->number);
1219 EXPORT_SYMBOL_GPL(xt_replace_table);
1221 struct xt_table *xt_register_table(struct net *net,
1222 const struct xt_table *input_table,
1223 struct xt_table_info *bootstrap,
1224 struct xt_table_info *newinfo)
1227 struct xt_table_info *private;
1228 struct xt_table *t, *table;
1230 /* Don't add one object to multiple lists. */
1231 table = kmemdup(input_table, sizeof(struct xt_table), GFP_KERNEL);
1237 mutex_lock(&xt[table->af].mutex);
1238 /* Don't autoload: we'd eat our tail... */
1239 list_for_each_entry(t, &net->xt.tables[table->af], list) {
1240 if (strcmp(t->name, table->name) == 0) {
1246 /* Simplifies replace_table code. */
1247 table->private = bootstrap;
1249 if (!xt_replace_table(table, 0, newinfo, &ret))
1252 private = table->private;
1253 pr_debug("table->private->number = %u\n", private->number);
1255 /* save number of initial entries */
1256 private->initial_entries = private->number;
1258 list_add(&table->list, &net->xt.tables[table->af]);
1259 mutex_unlock(&xt[table->af].mutex);
1263 mutex_unlock(&xt[table->af].mutex);
1266 return ERR_PTR(ret);
1268 EXPORT_SYMBOL_GPL(xt_register_table);
1270 void *xt_unregister_table(struct xt_table *table)
1272 struct xt_table_info *private;
1274 mutex_lock(&xt[table->af].mutex);
1275 private = table->private;
1276 list_del(&table->list);
1277 mutex_unlock(&xt[table->af].mutex);
1282 EXPORT_SYMBOL_GPL(xt_unregister_table);
1284 #ifdef CONFIG_PROC_FS
1285 struct xt_names_priv {
1286 struct seq_net_private p;
1289 static void *xt_table_seq_start(struct seq_file *seq, loff_t *pos)
1291 struct xt_names_priv *priv = seq->private;
1292 struct net *net = seq_file_net(seq);
1293 u_int8_t af = priv->af;
1295 mutex_lock(&xt[af].mutex);
1296 return seq_list_start(&net->xt.tables[af], *pos);
1299 static void *xt_table_seq_next(struct seq_file *seq, void *v, loff_t *pos)
1301 struct xt_names_priv *priv = seq->private;
1302 struct net *net = seq_file_net(seq);
1303 u_int8_t af = priv->af;
1305 return seq_list_next(v, &net->xt.tables[af], pos);
1308 static void xt_table_seq_stop(struct seq_file *seq, void *v)
1310 struct xt_names_priv *priv = seq->private;
1311 u_int8_t af = priv->af;
1313 mutex_unlock(&xt[af].mutex);
1316 static int xt_table_seq_show(struct seq_file *seq, void *v)
1318 struct xt_table *table = list_entry(v, struct xt_table, list);
1321 seq_printf(seq, "%s\n", table->name);
1325 static const struct seq_operations xt_table_seq_ops = {
1326 .start = xt_table_seq_start,
1327 .next = xt_table_seq_next,
1328 .stop = xt_table_seq_stop,
1329 .show = xt_table_seq_show,
1332 static int xt_table_open(struct inode *inode, struct file *file)
1335 struct xt_names_priv *priv;
1337 ret = seq_open_net(inode, file, &xt_table_seq_ops,
1338 sizeof(struct xt_names_priv));
1340 priv = ((struct seq_file *)file->private_data)->private;
1341 priv->af = (unsigned long)PDE_DATA(inode);
1346 static const struct file_operations xt_table_ops = {
1347 .owner = THIS_MODULE,
1348 .open = xt_table_open,
1350 .llseek = seq_lseek,
1351 .release = seq_release_net,
1355 * Traverse state for ip{,6}_{tables,matches} for helping crossing
1356 * the multi-AF mutexes.
1358 struct nf_mttg_trav {
1359 struct list_head *head, *curr;
1360 uint8_t class, nfproto;
1365 MTTG_TRAV_NFP_UNSPEC,
1370 static void *xt_mttg_seq_next(struct seq_file *seq, void *v, loff_t *ppos,
1373 static const uint8_t next_class[] = {
1374 [MTTG_TRAV_NFP_UNSPEC] = MTTG_TRAV_NFP_SPEC,
1375 [MTTG_TRAV_NFP_SPEC] = MTTG_TRAV_DONE,
1377 struct nf_mttg_trav *trav = seq->private;
1379 switch (trav->class) {
1380 case MTTG_TRAV_INIT:
1381 trav->class = MTTG_TRAV_NFP_UNSPEC;
1382 mutex_lock(&xt[NFPROTO_UNSPEC].mutex);
1383 trav->head = trav->curr = is_target ?
1384 &xt[NFPROTO_UNSPEC].target : &xt[NFPROTO_UNSPEC].match;
1386 case MTTG_TRAV_NFP_UNSPEC:
1387 trav->curr = trav->curr->next;
1388 if (trav->curr != trav->head)
1390 mutex_unlock(&xt[NFPROTO_UNSPEC].mutex);
1391 mutex_lock(&xt[trav->nfproto].mutex);
1392 trav->head = trav->curr = is_target ?
1393 &xt[trav->nfproto].target : &xt[trav->nfproto].match;
1394 trav->class = next_class[trav->class];
1396 case MTTG_TRAV_NFP_SPEC:
1397 trav->curr = trav->curr->next;
1398 if (trav->curr != trav->head)
1400 /* fallthru, _stop will unlock */
1410 static void *xt_mttg_seq_start(struct seq_file *seq, loff_t *pos,
1413 struct nf_mttg_trav *trav = seq->private;
1416 trav->class = MTTG_TRAV_INIT;
1417 for (j = 0; j < *pos; ++j)
1418 if (xt_mttg_seq_next(seq, NULL, NULL, is_target) == NULL)
1423 static void xt_mttg_seq_stop(struct seq_file *seq, void *v)
1425 struct nf_mttg_trav *trav = seq->private;
1427 switch (trav->class) {
1428 case MTTG_TRAV_NFP_UNSPEC:
1429 mutex_unlock(&xt[NFPROTO_UNSPEC].mutex);
1431 case MTTG_TRAV_NFP_SPEC:
1432 mutex_unlock(&xt[trav->nfproto].mutex);
1437 static void *xt_match_seq_start(struct seq_file *seq, loff_t *pos)
1439 return xt_mttg_seq_start(seq, pos, false);
1442 static void *xt_match_seq_next(struct seq_file *seq, void *v, loff_t *ppos)
1444 return xt_mttg_seq_next(seq, v, ppos, false);
1447 static int xt_match_seq_show(struct seq_file *seq, void *v)
1449 const struct nf_mttg_trav *trav = seq->private;
1450 const struct xt_match *match;
1452 switch (trav->class) {
1453 case MTTG_TRAV_NFP_UNSPEC:
1454 case MTTG_TRAV_NFP_SPEC:
1455 if (trav->curr == trav->head)
1457 match = list_entry(trav->curr, struct xt_match, list);
1459 seq_printf(seq, "%s\n", match->name);
1464 static const struct seq_operations xt_match_seq_ops = {
1465 .start = xt_match_seq_start,
1466 .next = xt_match_seq_next,
1467 .stop = xt_mttg_seq_stop,
1468 .show = xt_match_seq_show,
1471 static int xt_match_open(struct inode *inode, struct file *file)
1473 struct nf_mttg_trav *trav;
1474 trav = __seq_open_private(file, &xt_match_seq_ops, sizeof(*trav));
1478 trav->nfproto = (unsigned long)PDE_DATA(inode);
1482 static const struct file_operations xt_match_ops = {
1483 .owner = THIS_MODULE,
1484 .open = xt_match_open,
1486 .llseek = seq_lseek,
1487 .release = seq_release_private,
1490 static void *xt_target_seq_start(struct seq_file *seq, loff_t *pos)
1492 return xt_mttg_seq_start(seq, pos, true);
1495 static void *xt_target_seq_next(struct seq_file *seq, void *v, loff_t *ppos)
1497 return xt_mttg_seq_next(seq, v, ppos, true);
1500 static int xt_target_seq_show(struct seq_file *seq, void *v)
1502 const struct nf_mttg_trav *trav = seq->private;
1503 const struct xt_target *target;
1505 switch (trav->class) {
1506 case MTTG_TRAV_NFP_UNSPEC:
1507 case MTTG_TRAV_NFP_SPEC:
1508 if (trav->curr == trav->head)
1510 target = list_entry(trav->curr, struct xt_target, list);
1512 seq_printf(seq, "%s\n", target->name);
1517 static const struct seq_operations xt_target_seq_ops = {
1518 .start = xt_target_seq_start,
1519 .next = xt_target_seq_next,
1520 .stop = xt_mttg_seq_stop,
1521 .show = xt_target_seq_show,
1524 static int xt_target_open(struct inode *inode, struct file *file)
1526 struct nf_mttg_trav *trav;
1527 trav = __seq_open_private(file, &xt_target_seq_ops, sizeof(*trav));
1531 trav->nfproto = (unsigned long)PDE_DATA(inode);
1535 static const struct file_operations xt_target_ops = {
1536 .owner = THIS_MODULE,
1537 .open = xt_target_open,
1539 .llseek = seq_lseek,
1540 .release = seq_release_private,
1543 #define FORMAT_TABLES "_tables_names"
1544 #define FORMAT_MATCHES "_tables_matches"
1545 #define FORMAT_TARGETS "_tables_targets"
1547 #endif /* CONFIG_PROC_FS */
1550 * xt_hook_ops_alloc - set up hooks for a new table
1551 * @table: table with metadata needed to set up hooks
1552 * @fn: Hook function
1554 * This function will create the nf_hook_ops that the x_table needs
1555 * to hand to xt_hook_link_net().
1557 struct nf_hook_ops *
1558 xt_hook_ops_alloc(const struct xt_table *table, nf_hookfn *fn)
1560 unsigned int hook_mask = table->valid_hooks;
1561 uint8_t i, num_hooks = hweight32(hook_mask);
1563 struct nf_hook_ops *ops;
1566 return ERR_PTR(-EINVAL);
1568 ops = kcalloc(num_hooks, sizeof(*ops), GFP_KERNEL);
1570 return ERR_PTR(-ENOMEM);
1572 for (i = 0, hooknum = 0; i < num_hooks && hook_mask != 0;
1573 hook_mask >>= 1, ++hooknum) {
1574 if (!(hook_mask & 1))
1577 ops[i].pf = table->af;
1578 ops[i].hooknum = hooknum;
1579 ops[i].priority = table->priority;
1585 EXPORT_SYMBOL_GPL(xt_hook_ops_alloc);
1587 int xt_proto_init(struct net *net, u_int8_t af)
1589 #ifdef CONFIG_PROC_FS
1590 char buf[XT_FUNCTION_MAXNAMELEN];
1591 struct proc_dir_entry *proc;
1596 if (af >= ARRAY_SIZE(xt_prefix))
1600 #ifdef CONFIG_PROC_FS
1601 root_uid = make_kuid(net->user_ns, 0);
1602 root_gid = make_kgid(net->user_ns, 0);
1604 strlcpy(buf, xt_prefix[af], sizeof(buf));
1605 strlcat(buf, FORMAT_TABLES, sizeof(buf));
1606 proc = proc_create_data(buf, 0440, net->proc_net, &xt_table_ops,
1607 (void *)(unsigned long)af);
1610 if (uid_valid(root_uid) && gid_valid(root_gid))
1611 proc_set_user(proc, root_uid, root_gid);
1613 strlcpy(buf, xt_prefix[af], sizeof(buf));
1614 strlcat(buf, FORMAT_MATCHES, sizeof(buf));
1615 proc = proc_create_data(buf, 0440, net->proc_net, &xt_match_ops,
1616 (void *)(unsigned long)af);
1618 goto out_remove_tables;
1619 if (uid_valid(root_uid) && gid_valid(root_gid))
1620 proc_set_user(proc, root_uid, root_gid);
1622 strlcpy(buf, xt_prefix[af], sizeof(buf));
1623 strlcat(buf, FORMAT_TARGETS, sizeof(buf));
1624 proc = proc_create_data(buf, 0440, net->proc_net, &xt_target_ops,
1625 (void *)(unsigned long)af);
1627 goto out_remove_matches;
1628 if (uid_valid(root_uid) && gid_valid(root_gid))
1629 proc_set_user(proc, root_uid, root_gid);
1634 #ifdef CONFIG_PROC_FS
1636 strlcpy(buf, xt_prefix[af], sizeof(buf));
1637 strlcat(buf, FORMAT_MATCHES, sizeof(buf));
1638 remove_proc_entry(buf, net->proc_net);
1641 strlcpy(buf, xt_prefix[af], sizeof(buf));
1642 strlcat(buf, FORMAT_TABLES, sizeof(buf));
1643 remove_proc_entry(buf, net->proc_net);
1648 EXPORT_SYMBOL_GPL(xt_proto_init);
1650 void xt_proto_fini(struct net *net, u_int8_t af)
1652 #ifdef CONFIG_PROC_FS
1653 char buf[XT_FUNCTION_MAXNAMELEN];
1655 strlcpy(buf, xt_prefix[af], sizeof(buf));
1656 strlcat(buf, FORMAT_TABLES, sizeof(buf));
1657 remove_proc_entry(buf, net->proc_net);
1659 strlcpy(buf, xt_prefix[af], sizeof(buf));
1660 strlcat(buf, FORMAT_TARGETS, sizeof(buf));
1661 remove_proc_entry(buf, net->proc_net);
1663 strlcpy(buf, xt_prefix[af], sizeof(buf));
1664 strlcat(buf, FORMAT_MATCHES, sizeof(buf));
1665 remove_proc_entry(buf, net->proc_net);
1666 #endif /*CONFIG_PROC_FS*/
1668 EXPORT_SYMBOL_GPL(xt_proto_fini);
1671 * xt_percpu_counter_alloc - allocate x_tables rule counter
1673 * @state: pointer to xt_percpu allocation state
1674 * @counter: pointer to counter struct inside the ip(6)/arpt_entry struct
1676 * On SMP, the packet counter [ ip(6)t_entry->counters.pcnt ] will then
1677 * contain the address of the real (percpu) counter.
1679 * Rule evaluation needs to use xt_get_this_cpu_counter() helper
1680 * to fetch the real percpu counter.
1682 * To speed up allocation and improve data locality, a 4kb block is
1685 * xt_percpu_counter_alloc_state contains the base address of the
1686 * allocated page and the current sub-offset.
1688 * returns false on error.
1690 bool xt_percpu_counter_alloc(struct xt_percpu_counter_alloc_state *state,
1691 struct xt_counters *counter)
1693 BUILD_BUG_ON(XT_PCPU_BLOCK_SIZE < (sizeof(*counter) * 2));
1695 if (nr_cpu_ids <= 1)
1699 state->mem = __alloc_percpu(XT_PCPU_BLOCK_SIZE,
1700 XT_PCPU_BLOCK_SIZE);
1704 counter->pcnt = (__force unsigned long)(state->mem + state->off);
1705 state->off += sizeof(*counter);
1706 if (state->off > (XT_PCPU_BLOCK_SIZE - sizeof(*counter))) {
1712 EXPORT_SYMBOL_GPL(xt_percpu_counter_alloc);
1714 void xt_percpu_counter_free(struct xt_counters *counters)
1716 unsigned long pcnt = counters->pcnt;
1718 if (nr_cpu_ids > 1 && (pcnt & (XT_PCPU_BLOCK_SIZE - 1)) == 0)
1719 free_percpu((void __percpu *)pcnt);
1721 EXPORT_SYMBOL_GPL(xt_percpu_counter_free);
1723 static int __net_init xt_net_init(struct net *net)
1727 for (i = 0; i < NFPROTO_NUMPROTO; i++)
1728 INIT_LIST_HEAD(&net->xt.tables[i]);
1732 static void __net_exit xt_net_exit(struct net *net)
1736 for (i = 0; i < NFPROTO_NUMPROTO; i++)
1737 WARN_ON_ONCE(!list_empty(&net->xt.tables[i]));
1740 static struct pernet_operations xt_net_ops = {
1741 .init = xt_net_init,
1742 .exit = xt_net_exit,
1745 static int __init xt_init(void)
1750 for_each_possible_cpu(i) {
1751 seqcount_init(&per_cpu(xt_recseq, i));
1754 xt = kmalloc(sizeof(struct xt_af) * NFPROTO_NUMPROTO, GFP_KERNEL);
1758 for (i = 0; i < NFPROTO_NUMPROTO; i++) {
1759 mutex_init(&xt[i].mutex);
1760 #ifdef CONFIG_COMPAT
1761 mutex_init(&xt[i].compat_mutex);
1762 xt[i].compat_tab = NULL;
1764 INIT_LIST_HEAD(&xt[i].target);
1765 INIT_LIST_HEAD(&xt[i].match);
1767 rv = register_pernet_subsys(&xt_net_ops);
1773 static void __exit xt_fini(void)
1775 unregister_pernet_subsys(&xt_net_ops);
1779 module_init(xt_init);
1780 module_exit(xt_fini);