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 XT_PCPU_BLOCK_SIZE 4096
43 #define XT_MAX_TABLE_SIZE (512 * 1024 * 1024)
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 if (strnlen(name, XT_EXTENSION_MAXNAMELEN) == XT_EXTENSION_MAXNAMELEN)
214 return ERR_PTR(-EINVAL);
216 match = xt_find_match(nfproto, name, revision);
218 request_module("%st_%s", xt_prefix[nfproto], name);
219 match = xt_find_match(nfproto, name, revision);
224 EXPORT_SYMBOL_GPL(xt_request_find_match);
226 /* Find target, grabs ref. Returns ERR_PTR() on error. */
227 struct xt_target *xt_find_target(u8 af, const char *name, u8 revision)
232 mutex_lock(&xt[af].mutex);
233 list_for_each_entry(t, &xt[af].target, list) {
234 if (strcmp(t->name, name) == 0) {
235 if (t->revision == revision) {
236 if (try_module_get(t->me)) {
237 mutex_unlock(&xt[af].mutex);
241 err = -EPROTOTYPE; /* Found something. */
244 mutex_unlock(&xt[af].mutex);
246 if (af != NFPROTO_UNSPEC)
247 /* Try searching again in the family-independent list */
248 return xt_find_target(NFPROTO_UNSPEC, name, revision);
252 EXPORT_SYMBOL(xt_find_target);
254 struct xt_target *xt_request_find_target(u8 af, const char *name, u8 revision)
256 struct xt_target *target;
258 if (strnlen(name, XT_EXTENSION_MAXNAMELEN) == XT_EXTENSION_MAXNAMELEN)
259 return ERR_PTR(-EINVAL);
261 target = xt_find_target(af, name, revision);
262 if (IS_ERR(target)) {
263 request_module("%st_%s", xt_prefix[af], name);
264 target = xt_find_target(af, name, revision);
269 EXPORT_SYMBOL_GPL(xt_request_find_target);
272 static int xt_obj_to_user(u16 __user *psize, u16 size,
273 void __user *pname, const char *name,
274 u8 __user *prev, u8 rev)
276 if (put_user(size, psize))
278 if (copy_to_user(pname, name, strlen(name) + 1))
280 if (put_user(rev, prev))
286 #define XT_OBJ_TO_USER(U, K, TYPE, C_SIZE) \
287 xt_obj_to_user(&U->u.TYPE##_size, C_SIZE ? : K->u.TYPE##_size, \
288 U->u.user.name, K->u.kernel.TYPE->name, \
289 &U->u.user.revision, K->u.kernel.TYPE->revision)
291 int xt_data_to_user(void __user *dst, const void *src,
292 int usersize, int size, int aligned_size)
294 usersize = usersize ? : size;
295 if (copy_to_user(dst, src, usersize))
297 if (usersize != aligned_size &&
298 clear_user(dst + usersize, aligned_size - usersize))
303 EXPORT_SYMBOL_GPL(xt_data_to_user);
305 #define XT_DATA_TO_USER(U, K, TYPE) \
306 xt_data_to_user(U->data, K->data, \
307 K->u.kernel.TYPE->usersize, \
308 K->u.kernel.TYPE->TYPE##size, \
309 XT_ALIGN(K->u.kernel.TYPE->TYPE##size))
311 int xt_match_to_user(const struct xt_entry_match *m,
312 struct xt_entry_match __user *u)
314 return XT_OBJ_TO_USER(u, m, match, 0) ||
315 XT_DATA_TO_USER(u, m, match);
317 EXPORT_SYMBOL_GPL(xt_match_to_user);
319 int xt_target_to_user(const struct xt_entry_target *t,
320 struct xt_entry_target __user *u)
322 return XT_OBJ_TO_USER(u, t, target, 0) ||
323 XT_DATA_TO_USER(u, t, target);
325 EXPORT_SYMBOL_GPL(xt_target_to_user);
327 static int match_revfn(u8 af, const char *name, u8 revision, int *bestp)
329 const struct xt_match *m;
332 mutex_lock(&xt[af].mutex);
333 list_for_each_entry(m, &xt[af].match, list) {
334 if (strcmp(m->name, name) == 0) {
335 if (m->revision > *bestp)
336 *bestp = m->revision;
337 if (m->revision == revision)
341 mutex_unlock(&xt[af].mutex);
343 if (af != NFPROTO_UNSPEC && !have_rev)
344 return match_revfn(NFPROTO_UNSPEC, name, revision, bestp);
349 static int target_revfn(u8 af, const char *name, u8 revision, int *bestp)
351 const struct xt_target *t;
354 mutex_lock(&xt[af].mutex);
355 list_for_each_entry(t, &xt[af].target, list) {
356 if (strcmp(t->name, name) == 0) {
357 if (t->revision > *bestp)
358 *bestp = t->revision;
359 if (t->revision == revision)
363 mutex_unlock(&xt[af].mutex);
365 if (af != NFPROTO_UNSPEC && !have_rev)
366 return target_revfn(NFPROTO_UNSPEC, name, revision, bestp);
371 /* Returns true or false (if no such extension at all) */
372 int xt_find_revision(u8 af, const char *name, u8 revision, int target,
375 int have_rev, best = -1;
378 have_rev = target_revfn(af, name, revision, &best);
380 have_rev = match_revfn(af, name, revision, &best);
382 /* Nothing at all? Return 0 to try loading module. */
390 *err = -EPROTONOSUPPORT;
393 EXPORT_SYMBOL_GPL(xt_find_revision);
396 textify_hooks(char *buf, size_t size, unsigned int mask, uint8_t nfproto)
398 static const char *const inetbr_names[] = {
399 "PREROUTING", "INPUT", "FORWARD",
400 "OUTPUT", "POSTROUTING", "BROUTING",
402 static const char *const arp_names[] = {
403 "INPUT", "FORWARD", "OUTPUT",
405 const char *const *names;
411 names = (nfproto == NFPROTO_ARP) ? arp_names : inetbr_names;
412 max = (nfproto == NFPROTO_ARP) ? ARRAY_SIZE(arp_names) :
413 ARRAY_SIZE(inetbr_names);
415 for (i = 0; i < max; ++i) {
416 if (!(mask & (1 << i)))
418 res = snprintf(p, size, "%s%s", np ? "/" : "", names[i]);
430 * xt_check_proc_name - check that name is suitable for /proc file creation
432 * @name: file name candidate
433 * @size: length of buffer
435 * some x_tables modules wish to create a file in /proc.
436 * This function makes sure that the name is suitable for this
437 * purpose, it checks that name is NUL terminated and isn't a 'special'
440 * returns negative number on error or 0 if name is useable.
442 int xt_check_proc_name(const char *name, unsigned int size)
447 if (strnlen(name, size) == size)
448 return -ENAMETOOLONG;
450 if (strcmp(name, ".") == 0 ||
451 strcmp(name, "..") == 0 ||
457 EXPORT_SYMBOL(xt_check_proc_name);
459 int xt_check_match(struct xt_mtchk_param *par,
460 unsigned int size, u_int8_t proto, bool inv_proto)
464 if (XT_ALIGN(par->match->matchsize) != size &&
465 par->match->matchsize != -1) {
467 * ebt_among is exempt from centralized matchsize checking
468 * because it uses a dynamic-size data set.
470 pr_err("%s_tables: %s.%u match: invalid size "
471 "%u (kernel) != (user) %u\n",
472 xt_prefix[par->family], par->match->name,
473 par->match->revision,
474 XT_ALIGN(par->match->matchsize), size);
477 if (par->match->table != NULL &&
478 strcmp(par->match->table, par->table) != 0) {
479 pr_err("%s_tables: %s match: only valid in %s table, not %s\n",
480 xt_prefix[par->family], par->match->name,
481 par->match->table, par->table);
484 if (par->match->hooks && (par->hook_mask & ~par->match->hooks) != 0) {
485 char used[64], allow[64];
487 pr_err("%s_tables: %s match: used from hooks %s, but only "
489 xt_prefix[par->family], par->match->name,
490 textify_hooks(used, sizeof(used), par->hook_mask,
492 textify_hooks(allow, sizeof(allow), par->match->hooks,
496 if (par->match->proto && (par->match->proto != proto || inv_proto)) {
497 pr_err("%s_tables: %s match: only valid for protocol %u\n",
498 xt_prefix[par->family], par->match->name,
502 if (par->match->checkentry != NULL) {
503 ret = par->match->checkentry(par);
507 /* Flag up potential errors. */
512 EXPORT_SYMBOL_GPL(xt_check_match);
514 /** xt_check_entry_match - check that matches end before start of target
516 * @match: beginning of xt_entry_match
517 * @target: beginning of this rules target (alleged end of matches)
518 * @alignment: alignment requirement of match structures
520 * Validates that all matches add up to the beginning of the target,
521 * and that each match covers at least the base structure size.
523 * Return: 0 on success, negative errno on failure.
525 static int xt_check_entry_match(const char *match, const char *target,
526 const size_t alignment)
528 const struct xt_entry_match *pos;
529 int length = target - match;
531 if (length == 0) /* no matches */
534 pos = (struct xt_entry_match *)match;
536 if ((unsigned long)pos % alignment)
539 if (length < (int)sizeof(struct xt_entry_match))
542 if (pos->u.match_size < sizeof(struct xt_entry_match))
545 if (pos->u.match_size > length)
548 length -= pos->u.match_size;
549 pos = ((void *)((char *)(pos) + (pos)->u.match_size));
550 } while (length > 0);
556 int xt_compat_add_offset(u_int8_t af, unsigned int offset, int delta)
558 struct xt_af *xp = &xt[af];
560 if (WARN_ON(!xp->compat_tab))
563 if (xp->cur >= xp->number)
567 delta += xp->compat_tab[xp->cur - 1].delta;
568 xp->compat_tab[xp->cur].offset = offset;
569 xp->compat_tab[xp->cur].delta = delta;
573 EXPORT_SYMBOL_GPL(xt_compat_add_offset);
575 void xt_compat_flush_offsets(u_int8_t af)
577 if (xt[af].compat_tab) {
578 vfree(xt[af].compat_tab);
579 xt[af].compat_tab = NULL;
584 EXPORT_SYMBOL_GPL(xt_compat_flush_offsets);
586 int xt_compat_calc_jump(u_int8_t af, unsigned int offset)
588 struct compat_delta *tmp = xt[af].compat_tab;
589 int mid, left = 0, right = xt[af].cur - 1;
591 while (left <= right) {
592 mid = (left + right) >> 1;
593 if (offset > tmp[mid].offset)
595 else if (offset < tmp[mid].offset)
598 return mid ? tmp[mid - 1].delta : 0;
600 return left ? tmp[left - 1].delta : 0;
602 EXPORT_SYMBOL_GPL(xt_compat_calc_jump);
604 int xt_compat_init_offsets(u8 af, unsigned int number)
608 if (!number || number > (INT_MAX / sizeof(struct compat_delta)))
611 if (WARN_ON(xt[af].compat_tab))
614 mem = sizeof(struct compat_delta) * number;
615 if (mem > XT_MAX_TABLE_SIZE)
618 xt[af].compat_tab = vmalloc(mem);
619 if (!xt[af].compat_tab)
622 xt[af].number = number;
627 EXPORT_SYMBOL(xt_compat_init_offsets);
629 int xt_compat_match_offset(const struct xt_match *match)
631 u_int16_t csize = match->compatsize ? : match->matchsize;
632 return XT_ALIGN(match->matchsize) - COMPAT_XT_ALIGN(csize);
634 EXPORT_SYMBOL_GPL(xt_compat_match_offset);
636 void xt_compat_match_from_user(struct xt_entry_match *m, void **dstptr,
639 const struct xt_match *match = m->u.kernel.match;
640 struct compat_xt_entry_match *cm = (struct compat_xt_entry_match *)m;
641 int off = xt_compat_match_offset(match);
642 u_int16_t msize = cm->u.user.match_size;
643 char name[sizeof(m->u.user.name)];
646 memcpy(m, cm, sizeof(*cm));
647 if (match->compat_from_user)
648 match->compat_from_user(m->data, cm->data);
650 memcpy(m->data, cm->data, msize - sizeof(*cm));
653 m->u.user.match_size = msize;
654 strlcpy(name, match->name, sizeof(name));
655 module_put(match->me);
656 strncpy(m->u.user.name, name, sizeof(m->u.user.name));
661 EXPORT_SYMBOL_GPL(xt_compat_match_from_user);
663 #define COMPAT_XT_DATA_TO_USER(U, K, TYPE, C_SIZE) \
664 xt_data_to_user(U->data, K->data, \
665 K->u.kernel.TYPE->usersize, \
667 COMPAT_XT_ALIGN(C_SIZE))
669 int xt_compat_match_to_user(const struct xt_entry_match *m,
670 void __user **dstptr, unsigned int *size)
672 const struct xt_match *match = m->u.kernel.match;
673 struct compat_xt_entry_match __user *cm = *dstptr;
674 int off = xt_compat_match_offset(match);
675 u_int16_t msize = m->u.user.match_size - off;
677 if (XT_OBJ_TO_USER(cm, m, match, msize))
680 if (match->compat_to_user) {
681 if (match->compat_to_user((void __user *)cm->data, m->data))
684 if (COMPAT_XT_DATA_TO_USER(cm, m, match, msize - sizeof(*cm)))
692 EXPORT_SYMBOL_GPL(xt_compat_match_to_user);
694 /* non-compat version may have padding after verdict */
695 struct compat_xt_standard_target {
696 struct compat_xt_entry_target t;
697 compat_uint_t verdict;
700 int xt_compat_check_entry_offsets(const void *base, const char *elems,
701 unsigned int target_offset,
702 unsigned int next_offset)
704 long size_of_base_struct = elems - (const char *)base;
705 const struct compat_xt_entry_target *t;
706 const char *e = base;
708 if (target_offset < size_of_base_struct)
711 if (target_offset + sizeof(*t) > next_offset)
714 t = (void *)(e + target_offset);
715 if (t->u.target_size < sizeof(*t))
718 if (target_offset + t->u.target_size > next_offset)
721 if (strcmp(t->u.user.name, XT_STANDARD_TARGET) == 0 &&
722 COMPAT_XT_ALIGN(target_offset + sizeof(struct compat_xt_standard_target)) != next_offset)
725 /* compat_xt_entry match has less strict alignment requirements,
726 * otherwise they are identical. In case of padding differences
727 * we need to add compat version of xt_check_entry_match.
729 BUILD_BUG_ON(sizeof(struct compat_xt_entry_match) != sizeof(struct xt_entry_match));
731 return xt_check_entry_match(elems, base + target_offset,
732 __alignof__(struct compat_xt_entry_match));
734 EXPORT_SYMBOL(xt_compat_check_entry_offsets);
735 #endif /* CONFIG_COMPAT */
738 * xt_check_entry_offsets - validate arp/ip/ip6t_entry
740 * @base: pointer to arp/ip/ip6t_entry
741 * @elems: pointer to first xt_entry_match, i.e. ip(6)t_entry->elems
742 * @target_offset: the arp/ip/ip6_t->target_offset
743 * @next_offset: the arp/ip/ip6_t->next_offset
745 * validates that target_offset and next_offset are sane and that all
746 * match sizes (if any) align with the target offset.
748 * This function does not validate the targets or matches themselves, it
749 * only tests that all the offsets and sizes are correct, that all
750 * match structures are aligned, and that the last structure ends where
751 * the target structure begins.
753 * Also see xt_compat_check_entry_offsets for CONFIG_COMPAT version.
755 * The arp/ip/ip6t_entry structure @base must have passed following tests:
756 * - it must point to a valid memory location
757 * - base to base + next_offset must be accessible, i.e. not exceed allocated
760 * A well-formed entry looks like this:
762 * ip(6)t_entry match [mtdata] match [mtdata] target [tgdata] ip(6)t_entry
763 * e->elems[]-----' | |
767 * target_offset---------------------------------' |
768 * next_offset---------------------------------------------------'
770 * elems[]: flexible array member at end of ip(6)/arpt_entry struct.
771 * This is where matches (if any) and the target reside.
772 * target_offset: beginning of target.
773 * next_offset: start of the next rule; also: size of this rule.
774 * Since targets have a minimum size, target_offset + minlen <= next_offset.
776 * Every match stores its size, sum of sizes must not exceed target_offset.
778 * Return: 0 on success, negative errno on failure.
780 int xt_check_entry_offsets(const void *base,
782 unsigned int target_offset,
783 unsigned int next_offset)
785 long size_of_base_struct = elems - (const char *)base;
786 const struct xt_entry_target *t;
787 const char *e = base;
789 /* target start is within the ip/ip6/arpt_entry struct */
790 if (target_offset < size_of_base_struct)
793 if (target_offset + sizeof(*t) > next_offset)
796 t = (void *)(e + target_offset);
797 if (t->u.target_size < sizeof(*t))
800 if (target_offset + t->u.target_size > next_offset)
803 if (strcmp(t->u.user.name, XT_STANDARD_TARGET) == 0 &&
804 XT_ALIGN(target_offset + sizeof(struct xt_standard_target)) != next_offset)
807 return xt_check_entry_match(elems, base + target_offset,
808 __alignof__(struct xt_entry_match));
810 EXPORT_SYMBOL(xt_check_entry_offsets);
813 * xt_alloc_entry_offsets - allocate array to store rule head offsets
815 * @size: number of entries
817 * Return: NULL or kmalloc'd or vmalloc'd array
819 unsigned int *xt_alloc_entry_offsets(unsigned int size)
821 if (size > XT_MAX_TABLE_SIZE / sizeof(unsigned int))
824 return kvmalloc_array(size, sizeof(unsigned int), GFP_KERNEL | __GFP_ZERO);
827 EXPORT_SYMBOL(xt_alloc_entry_offsets);
830 * xt_find_jump_offset - check if target is a valid jump offset
832 * @offsets: array containing all valid rule start offsets of a rule blob
833 * @target: the jump target to search for
834 * @size: entries in @offset
836 bool xt_find_jump_offset(const unsigned int *offsets,
837 unsigned int target, unsigned int size)
839 int m, low = 0, hi = size;
844 if (offsets[m] > target)
846 else if (offsets[m] < target)
854 EXPORT_SYMBOL(xt_find_jump_offset);
856 int xt_check_target(struct xt_tgchk_param *par,
857 unsigned int size, u_int8_t proto, bool inv_proto)
861 if (XT_ALIGN(par->target->targetsize) != size) {
862 pr_err("%s_tables: %s.%u target: invalid size "
863 "%u (kernel) != (user) %u\n",
864 xt_prefix[par->family], par->target->name,
865 par->target->revision,
866 XT_ALIGN(par->target->targetsize), size);
869 if (par->target->table != NULL &&
870 strcmp(par->target->table, par->table) != 0) {
871 pr_err("%s_tables: %s target: only valid in %s table, not %s\n",
872 xt_prefix[par->family], par->target->name,
873 par->target->table, par->table);
876 if (par->target->hooks && (par->hook_mask & ~par->target->hooks) != 0) {
877 char used[64], allow[64];
879 pr_err("%s_tables: %s target: used from hooks %s, but only "
881 xt_prefix[par->family], par->target->name,
882 textify_hooks(used, sizeof(used), par->hook_mask,
884 textify_hooks(allow, sizeof(allow), par->target->hooks,
888 if (par->target->proto && (par->target->proto != proto || inv_proto)) {
889 pr_err("%s_tables: %s target: only valid for protocol %u\n",
890 xt_prefix[par->family], par->target->name,
894 if (par->target->checkentry != NULL) {
895 ret = par->target->checkentry(par);
899 /* Flag up potential errors. */
904 EXPORT_SYMBOL_GPL(xt_check_target);
907 * xt_copy_counters_from_user - copy counters and metadata from userspace
909 * @user: src pointer to userspace memory
910 * @len: alleged size of userspace memory
911 * @info: where to store the xt_counters_info metadata
912 * @compat: true if we setsockopt call is done by 32bit task on 64bit kernel
914 * Copies counter meta data from @user and stores it in @info.
916 * vmallocs memory to hold the counters, then copies the counter data
917 * from @user to the new memory and returns a pointer to it.
919 * If @compat is true, @info gets converted automatically to the 64bit
922 * The metadata associated with the counters is stored in @info.
924 * Return: returns pointer that caller has to test via IS_ERR().
925 * If IS_ERR is false, caller has to vfree the pointer.
927 void *xt_copy_counters_from_user(const void __user *user, unsigned int len,
928 struct xt_counters_info *info, bool compat)
935 /* structures only differ in size due to alignment */
936 struct compat_xt_counters_info compat_tmp;
938 if (len <= sizeof(compat_tmp))
939 return ERR_PTR(-EINVAL);
941 len -= sizeof(compat_tmp);
942 if (copy_from_user(&compat_tmp, user, sizeof(compat_tmp)) != 0)
943 return ERR_PTR(-EFAULT);
945 memcpy(info->name, compat_tmp.name, sizeof(info->name) - 1);
946 info->num_counters = compat_tmp.num_counters;
947 user += sizeof(compat_tmp);
951 if (len <= sizeof(*info))
952 return ERR_PTR(-EINVAL);
954 len -= sizeof(*info);
955 if (copy_from_user(info, user, sizeof(*info)) != 0)
956 return ERR_PTR(-EFAULT);
958 user += sizeof(*info);
960 info->name[sizeof(info->name) - 1] = '\0';
962 size = sizeof(struct xt_counters);
963 size *= info->num_counters;
965 if (size != (u64)len)
966 return ERR_PTR(-EINVAL);
970 return ERR_PTR(-ENOMEM);
972 if (copy_from_user(mem, user, len) == 0)
976 return ERR_PTR(-EFAULT);
978 EXPORT_SYMBOL_GPL(xt_copy_counters_from_user);
981 int xt_compat_target_offset(const struct xt_target *target)
983 u_int16_t csize = target->compatsize ? : target->targetsize;
984 return XT_ALIGN(target->targetsize) - COMPAT_XT_ALIGN(csize);
986 EXPORT_SYMBOL_GPL(xt_compat_target_offset);
988 void xt_compat_target_from_user(struct xt_entry_target *t, void **dstptr,
991 const struct xt_target *target = t->u.kernel.target;
992 struct compat_xt_entry_target *ct = (struct compat_xt_entry_target *)t;
993 int off = xt_compat_target_offset(target);
994 u_int16_t tsize = ct->u.user.target_size;
995 char name[sizeof(t->u.user.name)];
998 memcpy(t, ct, sizeof(*ct));
999 if (target->compat_from_user)
1000 target->compat_from_user(t->data, ct->data);
1002 memcpy(t->data, ct->data, tsize - sizeof(*ct));
1005 t->u.user.target_size = tsize;
1006 strlcpy(name, target->name, sizeof(name));
1007 module_put(target->me);
1008 strncpy(t->u.user.name, name, sizeof(t->u.user.name));
1013 EXPORT_SYMBOL_GPL(xt_compat_target_from_user);
1015 int xt_compat_target_to_user(const struct xt_entry_target *t,
1016 void __user **dstptr, unsigned int *size)
1018 const struct xt_target *target = t->u.kernel.target;
1019 struct compat_xt_entry_target __user *ct = *dstptr;
1020 int off = xt_compat_target_offset(target);
1021 u_int16_t tsize = t->u.user.target_size - off;
1023 if (XT_OBJ_TO_USER(ct, t, target, tsize))
1026 if (target->compat_to_user) {
1027 if (target->compat_to_user((void __user *)ct->data, t->data))
1030 if (COMPAT_XT_DATA_TO_USER(ct, t, target, tsize - sizeof(*ct)))
1038 EXPORT_SYMBOL_GPL(xt_compat_target_to_user);
1041 struct xt_table_info *xt_alloc_table_info(unsigned int size)
1043 struct xt_table_info *info = NULL;
1044 size_t sz = sizeof(*info) + size;
1046 if (sz < sizeof(*info) || sz >= XT_MAX_TABLE_SIZE)
1049 /* Pedantry: prevent them from hitting BUG() in vmalloc.c --RR */
1050 if ((size >> PAGE_SHIFT) + 2 > totalram_pages)
1053 /* __GFP_NORETRY is not fully supported by kvmalloc but it should
1054 * work reasonably well if sz is too large and bail out rather
1055 * than shoot all processes down before realizing there is nothing
1058 info = kvmalloc(sz, GFP_KERNEL | __GFP_NORETRY);
1062 memset(info, 0, sizeof(*info));
1066 EXPORT_SYMBOL(xt_alloc_table_info);
1068 void xt_free_table_info(struct xt_table_info *info)
1072 if (info->jumpstack != NULL) {
1073 for_each_possible_cpu(cpu)
1074 kvfree(info->jumpstack[cpu]);
1075 kvfree(info->jumpstack);
1080 EXPORT_SYMBOL(xt_free_table_info);
1082 /* Find table by name, grabs mutex & ref. Returns NULL on error. */
1083 struct xt_table *xt_find_table_lock(struct net *net, u_int8_t af,
1086 struct xt_table *t, *found = NULL;
1088 mutex_lock(&xt[af].mutex);
1089 list_for_each_entry(t, &net->xt.tables[af], list)
1090 if (strcmp(t->name, name) == 0 && try_module_get(t->me))
1093 if (net == &init_net)
1096 /* Table doesn't exist in this netns, re-try init */
1097 list_for_each_entry(t, &init_net.xt.tables[af], list) {
1098 if (strcmp(t->name, name))
1100 if (!try_module_get(t->me)) {
1101 mutex_unlock(&xt[af].mutex);
1105 mutex_unlock(&xt[af].mutex);
1106 if (t->table_init(net) != 0) {
1113 mutex_lock(&xt[af].mutex);
1120 /* and once again: */
1121 list_for_each_entry(t, &net->xt.tables[af], list)
1122 if (strcmp(t->name, name) == 0)
1125 module_put(found->me);
1127 mutex_unlock(&xt[af].mutex);
1130 EXPORT_SYMBOL_GPL(xt_find_table_lock);
1132 void xt_table_unlock(struct xt_table *table)
1134 mutex_unlock(&xt[table->af].mutex);
1136 EXPORT_SYMBOL_GPL(xt_table_unlock);
1138 #ifdef CONFIG_COMPAT
1139 void xt_compat_lock(u_int8_t af)
1141 mutex_lock(&xt[af].compat_mutex);
1143 EXPORT_SYMBOL_GPL(xt_compat_lock);
1145 void xt_compat_unlock(u_int8_t af)
1147 mutex_unlock(&xt[af].compat_mutex);
1149 EXPORT_SYMBOL_GPL(xt_compat_unlock);
1152 DEFINE_PER_CPU(seqcount_t, xt_recseq);
1153 EXPORT_PER_CPU_SYMBOL_GPL(xt_recseq);
1155 struct static_key xt_tee_enabled __read_mostly;
1156 EXPORT_SYMBOL_GPL(xt_tee_enabled);
1158 static int xt_jumpstack_alloc(struct xt_table_info *i)
1163 size = sizeof(void **) * nr_cpu_ids;
1164 if (size > PAGE_SIZE)
1165 i->jumpstack = kvzalloc(size, GFP_KERNEL);
1167 i->jumpstack = kzalloc(size, GFP_KERNEL);
1168 if (i->jumpstack == NULL)
1171 /* ruleset without jumps -- no stack needed */
1172 if (i->stacksize == 0)
1175 /* Jumpstack needs to be able to record two full callchains, one
1176 * from the first rule set traversal, plus one table reentrancy
1177 * via -j TEE without clobbering the callchain that brought us to
1180 * This is done by allocating two jumpstacks per cpu, on reentry
1181 * the upper half of the stack is used.
1183 * see the jumpstack setup in ipt_do_table() for more details.
1185 size = sizeof(void *) * i->stacksize * 2u;
1186 for_each_possible_cpu(cpu) {
1187 i->jumpstack[cpu] = kvmalloc_node(size, GFP_KERNEL,
1189 if (i->jumpstack[cpu] == NULL)
1191 * Freeing will be done later on by the callers. The
1192 * chain is: xt_replace_table -> __do_replace ->
1193 * do_replace -> xt_free_table_info.
1201 struct xt_counters *xt_counters_alloc(unsigned int counters)
1203 struct xt_counters *mem;
1205 if (counters == 0 || counters > INT_MAX / sizeof(*mem))
1208 counters *= sizeof(*mem);
1209 if (counters > XT_MAX_TABLE_SIZE)
1212 return vzalloc(counters);
1214 EXPORT_SYMBOL(xt_counters_alloc);
1216 struct xt_table_info *
1217 xt_replace_table(struct xt_table *table,
1218 unsigned int num_counters,
1219 struct xt_table_info *newinfo,
1222 struct xt_table_info *private;
1225 ret = xt_jumpstack_alloc(newinfo);
1231 /* Do the substitution. */
1233 private = table->private;
1235 /* Check inside lock: is the old number correct? */
1236 if (num_counters != private->number) {
1237 pr_debug("num_counters != table->private->number (%u/%u)\n",
1238 num_counters, private->number);
1244 newinfo->initial_entries = private->initial_entries;
1246 * Ensure contents of newinfo are visible before assigning to
1250 table->private = newinfo;
1252 /* make sure all cpus see new ->private value */
1256 * Even though table entries have now been swapped, other CPU's
1257 * may still be using the old entries. This is okay, because
1258 * resynchronization happens because of the locking done
1259 * during the get_counters() routine.
1264 if (audit_enabled) {
1265 audit_log(current->audit_context, GFP_KERNEL,
1266 AUDIT_NETFILTER_CFG,
1267 "table=%s family=%u entries=%u",
1268 table->name, table->af, private->number);
1274 EXPORT_SYMBOL_GPL(xt_replace_table);
1276 struct xt_table *xt_register_table(struct net *net,
1277 const struct xt_table *input_table,
1278 struct xt_table_info *bootstrap,
1279 struct xt_table_info *newinfo)
1282 struct xt_table_info *private;
1283 struct xt_table *t, *table;
1285 /* Don't add one object to multiple lists. */
1286 table = kmemdup(input_table, sizeof(struct xt_table), GFP_KERNEL);
1292 mutex_lock(&xt[table->af].mutex);
1293 /* Don't autoload: we'd eat our tail... */
1294 list_for_each_entry(t, &net->xt.tables[table->af], list) {
1295 if (strcmp(t->name, table->name) == 0) {
1301 /* Simplifies replace_table code. */
1302 table->private = bootstrap;
1304 if (!xt_replace_table(table, 0, newinfo, &ret))
1307 private = table->private;
1308 pr_debug("table->private->number = %u\n", private->number);
1310 /* save number of initial entries */
1311 private->initial_entries = private->number;
1313 list_add(&table->list, &net->xt.tables[table->af]);
1314 mutex_unlock(&xt[table->af].mutex);
1318 mutex_unlock(&xt[table->af].mutex);
1321 return ERR_PTR(ret);
1323 EXPORT_SYMBOL_GPL(xt_register_table);
1325 void *xt_unregister_table(struct xt_table *table)
1327 struct xt_table_info *private;
1329 mutex_lock(&xt[table->af].mutex);
1330 private = table->private;
1331 list_del(&table->list);
1332 mutex_unlock(&xt[table->af].mutex);
1337 EXPORT_SYMBOL_GPL(xt_unregister_table);
1339 #ifdef CONFIG_PROC_FS
1340 struct xt_names_priv {
1341 struct seq_net_private p;
1344 static void *xt_table_seq_start(struct seq_file *seq, loff_t *pos)
1346 struct xt_names_priv *priv = seq->private;
1347 struct net *net = seq_file_net(seq);
1348 u_int8_t af = priv->af;
1350 mutex_lock(&xt[af].mutex);
1351 return seq_list_start(&net->xt.tables[af], *pos);
1354 static void *xt_table_seq_next(struct seq_file *seq, void *v, loff_t *pos)
1356 struct xt_names_priv *priv = seq->private;
1357 struct net *net = seq_file_net(seq);
1358 u_int8_t af = priv->af;
1360 return seq_list_next(v, &net->xt.tables[af], pos);
1363 static void xt_table_seq_stop(struct seq_file *seq, void *v)
1365 struct xt_names_priv *priv = seq->private;
1366 u_int8_t af = priv->af;
1368 mutex_unlock(&xt[af].mutex);
1371 static int xt_table_seq_show(struct seq_file *seq, void *v)
1373 struct xt_table *table = list_entry(v, struct xt_table, list);
1376 seq_printf(seq, "%s\n", table->name);
1380 static const struct seq_operations xt_table_seq_ops = {
1381 .start = xt_table_seq_start,
1382 .next = xt_table_seq_next,
1383 .stop = xt_table_seq_stop,
1384 .show = xt_table_seq_show,
1387 static int xt_table_open(struct inode *inode, struct file *file)
1390 struct xt_names_priv *priv;
1392 ret = seq_open_net(inode, file, &xt_table_seq_ops,
1393 sizeof(struct xt_names_priv));
1395 priv = ((struct seq_file *)file->private_data)->private;
1396 priv->af = (unsigned long)PDE_DATA(inode);
1401 static const struct file_operations xt_table_ops = {
1402 .owner = THIS_MODULE,
1403 .open = xt_table_open,
1405 .llseek = seq_lseek,
1406 .release = seq_release_net,
1410 * Traverse state for ip{,6}_{tables,matches} for helping crossing
1411 * the multi-AF mutexes.
1413 struct nf_mttg_trav {
1414 struct list_head *head, *curr;
1415 uint8_t class, nfproto;
1420 MTTG_TRAV_NFP_UNSPEC,
1425 static void *xt_mttg_seq_next(struct seq_file *seq, void *v, loff_t *ppos,
1428 static const uint8_t next_class[] = {
1429 [MTTG_TRAV_NFP_UNSPEC] = MTTG_TRAV_NFP_SPEC,
1430 [MTTG_TRAV_NFP_SPEC] = MTTG_TRAV_DONE,
1432 struct nf_mttg_trav *trav = seq->private;
1434 switch (trav->class) {
1435 case MTTG_TRAV_INIT:
1436 trav->class = MTTG_TRAV_NFP_UNSPEC;
1437 mutex_lock(&xt[NFPROTO_UNSPEC].mutex);
1438 trav->head = trav->curr = is_target ?
1439 &xt[NFPROTO_UNSPEC].target : &xt[NFPROTO_UNSPEC].match;
1441 case MTTG_TRAV_NFP_UNSPEC:
1442 trav->curr = trav->curr->next;
1443 if (trav->curr != trav->head)
1445 mutex_unlock(&xt[NFPROTO_UNSPEC].mutex);
1446 mutex_lock(&xt[trav->nfproto].mutex);
1447 trav->head = trav->curr = is_target ?
1448 &xt[trav->nfproto].target : &xt[trav->nfproto].match;
1449 trav->class = next_class[trav->class];
1451 case MTTG_TRAV_NFP_SPEC:
1452 trav->curr = trav->curr->next;
1453 if (trav->curr != trav->head)
1455 /* fallthru, _stop will unlock */
1465 static void *xt_mttg_seq_start(struct seq_file *seq, loff_t *pos,
1468 struct nf_mttg_trav *trav = seq->private;
1471 trav->class = MTTG_TRAV_INIT;
1472 for (j = 0; j < *pos; ++j)
1473 if (xt_mttg_seq_next(seq, NULL, NULL, is_target) == NULL)
1478 static void xt_mttg_seq_stop(struct seq_file *seq, void *v)
1480 struct nf_mttg_trav *trav = seq->private;
1482 switch (trav->class) {
1483 case MTTG_TRAV_NFP_UNSPEC:
1484 mutex_unlock(&xt[NFPROTO_UNSPEC].mutex);
1486 case MTTG_TRAV_NFP_SPEC:
1487 mutex_unlock(&xt[trav->nfproto].mutex);
1492 static void *xt_match_seq_start(struct seq_file *seq, loff_t *pos)
1494 return xt_mttg_seq_start(seq, pos, false);
1497 static void *xt_match_seq_next(struct seq_file *seq, void *v, loff_t *ppos)
1499 return xt_mttg_seq_next(seq, v, ppos, false);
1502 static int xt_match_seq_show(struct seq_file *seq, void *v)
1504 const struct nf_mttg_trav *trav = seq->private;
1505 const struct xt_match *match;
1507 switch (trav->class) {
1508 case MTTG_TRAV_NFP_UNSPEC:
1509 case MTTG_TRAV_NFP_SPEC:
1510 if (trav->curr == trav->head)
1512 match = list_entry(trav->curr, struct xt_match, list);
1514 seq_printf(seq, "%s\n", match->name);
1519 static const struct seq_operations xt_match_seq_ops = {
1520 .start = xt_match_seq_start,
1521 .next = xt_match_seq_next,
1522 .stop = xt_mttg_seq_stop,
1523 .show = xt_match_seq_show,
1526 static int xt_match_open(struct inode *inode, struct file *file)
1528 struct nf_mttg_trav *trav;
1529 trav = __seq_open_private(file, &xt_match_seq_ops, sizeof(*trav));
1533 trav->nfproto = (unsigned long)PDE_DATA(inode);
1537 static const struct file_operations xt_match_ops = {
1538 .owner = THIS_MODULE,
1539 .open = xt_match_open,
1541 .llseek = seq_lseek,
1542 .release = seq_release_private,
1545 static void *xt_target_seq_start(struct seq_file *seq, loff_t *pos)
1547 return xt_mttg_seq_start(seq, pos, true);
1550 static void *xt_target_seq_next(struct seq_file *seq, void *v, loff_t *ppos)
1552 return xt_mttg_seq_next(seq, v, ppos, true);
1555 static int xt_target_seq_show(struct seq_file *seq, void *v)
1557 const struct nf_mttg_trav *trav = seq->private;
1558 const struct xt_target *target;
1560 switch (trav->class) {
1561 case MTTG_TRAV_NFP_UNSPEC:
1562 case MTTG_TRAV_NFP_SPEC:
1563 if (trav->curr == trav->head)
1565 target = list_entry(trav->curr, struct xt_target, list);
1567 seq_printf(seq, "%s\n", target->name);
1572 static const struct seq_operations xt_target_seq_ops = {
1573 .start = xt_target_seq_start,
1574 .next = xt_target_seq_next,
1575 .stop = xt_mttg_seq_stop,
1576 .show = xt_target_seq_show,
1579 static int xt_target_open(struct inode *inode, struct file *file)
1581 struct nf_mttg_trav *trav;
1582 trav = __seq_open_private(file, &xt_target_seq_ops, sizeof(*trav));
1586 trav->nfproto = (unsigned long)PDE_DATA(inode);
1590 static const struct file_operations xt_target_ops = {
1591 .owner = THIS_MODULE,
1592 .open = xt_target_open,
1594 .llseek = seq_lseek,
1595 .release = seq_release_private,
1598 #define FORMAT_TABLES "_tables_names"
1599 #define FORMAT_MATCHES "_tables_matches"
1600 #define FORMAT_TARGETS "_tables_targets"
1602 #endif /* CONFIG_PROC_FS */
1605 * xt_hook_ops_alloc - set up hooks for a new table
1606 * @table: table with metadata needed to set up hooks
1607 * @fn: Hook function
1609 * This function will create the nf_hook_ops that the x_table needs
1610 * to hand to xt_hook_link_net().
1612 struct nf_hook_ops *
1613 xt_hook_ops_alloc(const struct xt_table *table, nf_hookfn *fn)
1615 unsigned int hook_mask = table->valid_hooks;
1616 uint8_t i, num_hooks = hweight32(hook_mask);
1618 struct nf_hook_ops *ops;
1621 return ERR_PTR(-EINVAL);
1623 ops = kcalloc(num_hooks, sizeof(*ops), GFP_KERNEL);
1625 return ERR_PTR(-ENOMEM);
1627 for (i = 0, hooknum = 0; i < num_hooks && hook_mask != 0;
1628 hook_mask >>= 1, ++hooknum) {
1629 if (!(hook_mask & 1))
1632 ops[i].pf = table->af;
1633 ops[i].hooknum = hooknum;
1634 ops[i].priority = table->priority;
1640 EXPORT_SYMBOL_GPL(xt_hook_ops_alloc);
1642 int xt_proto_init(struct net *net, u_int8_t af)
1644 #ifdef CONFIG_PROC_FS
1645 char buf[XT_FUNCTION_MAXNAMELEN];
1646 struct proc_dir_entry *proc;
1651 if (af >= ARRAY_SIZE(xt_prefix))
1655 #ifdef CONFIG_PROC_FS
1656 root_uid = make_kuid(net->user_ns, 0);
1657 root_gid = make_kgid(net->user_ns, 0);
1659 strlcpy(buf, xt_prefix[af], sizeof(buf));
1660 strlcat(buf, FORMAT_TABLES, sizeof(buf));
1661 proc = proc_create_data(buf, 0440, net->proc_net, &xt_table_ops,
1662 (void *)(unsigned long)af);
1665 if (uid_valid(root_uid) && gid_valid(root_gid))
1666 proc_set_user(proc, root_uid, root_gid);
1668 strlcpy(buf, xt_prefix[af], sizeof(buf));
1669 strlcat(buf, FORMAT_MATCHES, sizeof(buf));
1670 proc = proc_create_data(buf, 0440, net->proc_net, &xt_match_ops,
1671 (void *)(unsigned long)af);
1673 goto out_remove_tables;
1674 if (uid_valid(root_uid) && gid_valid(root_gid))
1675 proc_set_user(proc, root_uid, root_gid);
1677 strlcpy(buf, xt_prefix[af], sizeof(buf));
1678 strlcat(buf, FORMAT_TARGETS, sizeof(buf));
1679 proc = proc_create_data(buf, 0440, net->proc_net, &xt_target_ops,
1680 (void *)(unsigned long)af);
1682 goto out_remove_matches;
1683 if (uid_valid(root_uid) && gid_valid(root_gid))
1684 proc_set_user(proc, root_uid, root_gid);
1689 #ifdef CONFIG_PROC_FS
1691 strlcpy(buf, xt_prefix[af], sizeof(buf));
1692 strlcat(buf, FORMAT_MATCHES, sizeof(buf));
1693 remove_proc_entry(buf, net->proc_net);
1696 strlcpy(buf, xt_prefix[af], sizeof(buf));
1697 strlcat(buf, FORMAT_TABLES, sizeof(buf));
1698 remove_proc_entry(buf, net->proc_net);
1703 EXPORT_SYMBOL_GPL(xt_proto_init);
1705 void xt_proto_fini(struct net *net, u_int8_t af)
1707 #ifdef CONFIG_PROC_FS
1708 char buf[XT_FUNCTION_MAXNAMELEN];
1710 strlcpy(buf, xt_prefix[af], sizeof(buf));
1711 strlcat(buf, FORMAT_TABLES, sizeof(buf));
1712 remove_proc_entry(buf, net->proc_net);
1714 strlcpy(buf, xt_prefix[af], sizeof(buf));
1715 strlcat(buf, FORMAT_TARGETS, sizeof(buf));
1716 remove_proc_entry(buf, net->proc_net);
1718 strlcpy(buf, xt_prefix[af], sizeof(buf));
1719 strlcat(buf, FORMAT_MATCHES, sizeof(buf));
1720 remove_proc_entry(buf, net->proc_net);
1721 #endif /*CONFIG_PROC_FS*/
1723 EXPORT_SYMBOL_GPL(xt_proto_fini);
1726 * xt_percpu_counter_alloc - allocate x_tables rule counter
1728 * @state: pointer to xt_percpu allocation state
1729 * @counter: pointer to counter struct inside the ip(6)/arpt_entry struct
1731 * On SMP, the packet counter [ ip(6)t_entry->counters.pcnt ] will then
1732 * contain the address of the real (percpu) counter.
1734 * Rule evaluation needs to use xt_get_this_cpu_counter() helper
1735 * to fetch the real percpu counter.
1737 * To speed up allocation and improve data locality, a 4kb block is
1740 * xt_percpu_counter_alloc_state contains the base address of the
1741 * allocated page and the current sub-offset.
1743 * returns false on error.
1745 bool xt_percpu_counter_alloc(struct xt_percpu_counter_alloc_state *state,
1746 struct xt_counters *counter)
1748 BUILD_BUG_ON(XT_PCPU_BLOCK_SIZE < (sizeof(*counter) * 2));
1750 if (nr_cpu_ids <= 1)
1754 state->mem = __alloc_percpu(XT_PCPU_BLOCK_SIZE,
1755 XT_PCPU_BLOCK_SIZE);
1759 counter->pcnt = (__force unsigned long)(state->mem + state->off);
1760 state->off += sizeof(*counter);
1761 if (state->off > (XT_PCPU_BLOCK_SIZE - sizeof(*counter))) {
1767 EXPORT_SYMBOL_GPL(xt_percpu_counter_alloc);
1769 void xt_percpu_counter_free(struct xt_counters *counters)
1771 unsigned long pcnt = counters->pcnt;
1773 if (nr_cpu_ids > 1 && (pcnt & (XT_PCPU_BLOCK_SIZE - 1)) == 0)
1774 free_percpu((void __percpu *)pcnt);
1776 EXPORT_SYMBOL_GPL(xt_percpu_counter_free);
1778 static int __net_init xt_net_init(struct net *net)
1782 for (i = 0; i < NFPROTO_NUMPROTO; i++)
1783 INIT_LIST_HEAD(&net->xt.tables[i]);
1787 static struct pernet_operations xt_net_ops = {
1788 .init = xt_net_init,
1791 static int __init xt_init(void)
1796 for_each_possible_cpu(i) {
1797 seqcount_init(&per_cpu(xt_recseq, i));
1800 xt = kcalloc(NFPROTO_NUMPROTO, sizeof(struct xt_af), GFP_KERNEL);
1804 for (i = 0; i < NFPROTO_NUMPROTO; i++) {
1805 mutex_init(&xt[i].mutex);
1806 #ifdef CONFIG_COMPAT
1807 mutex_init(&xt[i].compat_mutex);
1808 xt[i].compat_tab = NULL;
1810 INIT_LIST_HEAD(&xt[i].target);
1811 INIT_LIST_HEAD(&xt[i].match);
1813 rv = register_pernet_subsys(&xt_net_ops);
1819 static void __exit xt_fini(void)
1821 unregister_pernet_subsys(&xt_net_ops);
1825 module_init(xt_init);
1826 module_exit(xt_fini);