Commit message: netfilter: add back stackpointer size checks

The rationale for removing the check is only correct for rulesets
generated by ip(6)tables.

In iptables, a jump can only occur to a user-defined chain, i.e.
because we size the stack based on number of user-defined chains we
cannot exceed stack size.

However, the underlying binary format has no such restriction,
and the validation step only ensures that the jump target is a
valid rule start point.

IOW, its possible to build a rule blob that has no user-defined
chains but does contain a jump.

If this happens, no jump stack gets allocated and crash occurs
because no jumpstack was allocated.

Fixes: 7814b6ec6d0d6 ("netfilter: xtables: don't save/restore jumpstack offset")
Reported-by: syzbot+e783f671527912cd9403@syzkaller.appspotmail.com
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
CVE: CVE-2018-1065
CWE: CWE-476
Vulnerability description: The netfilter subsystem in the Linux kernel through 4.15.7 mishandles the case of a rule blob that contains a jump but lacks a user-defined chain, which allows local users to cause a denial of service (NULL pointer dereference) by leveraging the CAP_NET_RAW or CAP_NET_ADMIN capability, related to arpt_do_table in net/ipv4/netfilter/arp_tables.c, ipt_do_table in net/ipv4/netfilter/ip_tables.c, and ip6t_do_table in net/ipv6/netfilter/ip6_tables.c.

Project: linux

static int __do_replace(struct net *net, const char *name,
			unsigned int valid_hooks,
			struct xt_table_info *newinfo,
			unsigned int num_counters,
			void __user *counters_ptr)
{
	int ret;
	struct xt_table *t;
	struct xt_table_info *oldinfo;
	struct xt_counters *counters;
	void *loc_cpu_old_entry;
	struct arpt_entry *iter;

	ret = 0;
	counters = vzalloc(num_counters * sizeof(struct xt_counters));
	if (!counters) {
		ret = -ENOMEM;
		goto out;
	}

	t = xt_request_find_table_lock(net, NFPROTO_ARP, name);
	if (IS_ERR(t)) {
		ret = PTR_ERR(t);
		goto free_newinfo_counters_untrans;
	}

	/* You lied! */
	if (valid_hooks != t->valid_hooks) {
		ret = -EINVAL;
		goto put_module;
	}

	oldinfo = xt_replace_table(t, num_counters, newinfo, &ret);
	if (!oldinfo)
		goto put_module;

	/* Update module usage count based on number of rules */
	if ((oldinfo->number > oldinfo->initial_entries) ||
	    (newinfo->number <= oldinfo->initial_entries))
		module_put(t->me);
	if ((oldinfo->number > oldinfo->initial_entries) &&
	    (newinfo->number <= oldinfo->initial_entries))
		module_put(t->me);

	get_old_counters(oldinfo, counters);

	/* Decrease module usage counts and free resource */
	loc_cpu_old_entry = oldinfo->entries;
	xt_entry_foreach(iter, loc_cpu_old_entry, oldinfo->size)
		cleanup_entry(iter);

	xt_free_table_info(oldinfo);
	if (copy_to_user(counters_ptr, counters,
			 sizeof(struct xt_counters) * num_counters) != 0) {
		/* Silent error, can't fail, new table is already in place */
		net_warn_ratelimited("arptables: counters copy to user failed while replacing table\n");
	}
	vfree(counters);
	xt_table_unlock(t);
	return ret;

 put_module:
	module_put(t->me);
	xt_table_unlock(t);
 free_newinfo_counters_untrans:
	vfree(counters);
 out:
	return ret;
}

Project: linux

static inline int arp_checkentry(const struct arpt_arp *arp)
{
	if (arp->flags & ~ARPT_F_MASK)
		return 0;
	if (arp->invflags & ~ARPT_INV_MASK)
		return 0;

	return 1;
}

Project: linux

static int __init arp_tables_init(void)
{
	int ret;

	ret = register_pernet_subsys(&arp_tables_net_ops);
	if (ret < 0)
		goto err1;

	/* No one else will be downing sem now, so we won't sleep */
	ret = xt_register_targets(arpt_builtin_tg, ARRAY_SIZE(arpt_builtin_tg));
	if (ret < 0)
		goto err2;

	/* Register setsockopt */
	ret = nf_register_sockopt(&arpt_sockopts);
	if (ret < 0)
		goto err4;

	return 0;

err4:
	xt_unregister_targets(arpt_builtin_tg, ARRAY_SIZE(arpt_builtin_tg));
err2:
	unregister_pernet_subsys(&arp_tables_net_ops);
err1:
	return ret;
}

Project: linux

int arpt_register_table(struct net *net,
			const struct xt_table *table,
			const struct arpt_replace *repl,
			const struct nf_hook_ops *ops,
			struct xt_table **res)
{
	int ret;
	struct xt_table_info *newinfo;
	struct xt_table_info bootstrap = {0};
	void *loc_cpu_entry;
	struct xt_table *new_table;

	newinfo = xt_alloc_table_info(repl->size);
	if (!newinfo)
		return -ENOMEM;

	loc_cpu_entry = newinfo->entries;
	memcpy(loc_cpu_entry, repl->entries, repl->size);

	ret = translate_table(newinfo, loc_cpu_entry, repl);
	if (ret != 0)
		goto out_free;

	new_table = xt_register_table(net, table, &bootstrap, newinfo);
	if (IS_ERR(new_table)) {
		ret = PTR_ERR(new_table);
		goto out_free;
	}

	/* set res now, will see skbs right after nf_register_net_hooks */
	WRITE_ONCE(*res, new_table);

	ret = nf_register_net_hooks(net, ops, hweight32(table->valid_hooks));
	if (ret != 0) {
		__arpt_unregister_table(new_table);
		*res = NULL;
	}

	return ret;

out_free:
	xt_free_table_info(newinfo);
	return ret;
}

Project: linux

check_compat_entry_size_and_hooks(struct compat_arpt_entry *e,
				  struct xt_table_info *newinfo,
				  unsigned int *size,
				  const unsigned char *base,
				  const unsigned char *limit)
{
	struct xt_entry_target *t;
	struct xt_target *target;
	unsigned int entry_offset;
	int ret, off;

	if ((unsigned long)e % __alignof__(struct compat_arpt_entry) != 0 ||
	    (unsigned char *)e + sizeof(struct compat_arpt_entry) >= limit ||
	    (unsigned char *)e + e->next_offset > limit)
		return -EINVAL;

	if (e->next_offset < sizeof(struct compat_arpt_entry) +
			     sizeof(struct compat_xt_entry_target))
		return -EINVAL;

	if (!arp_checkentry(&e->arp))
		return -EINVAL;

	ret = xt_compat_check_entry_offsets(e, e->elems, e->target_offset,
					    e->next_offset);
	if (ret)
		return ret;

	off = sizeof(struct arpt_entry) - sizeof(struct compat_arpt_entry);
	entry_offset = (void *)e - (void *)base;

	t = compat_arpt_get_target(e);
	target = xt_request_find_target(NFPROTO_ARP, t->u.user.name,
					t->u.user.revision);
	if (IS_ERR(target)) {
		ret = PTR_ERR(target);
		goto out;
	}
	t->u.kernel.target = target;

	off += xt_compat_target_offset(target);
	*size += off;
	ret = xt_compat_add_offset(NFPROTO_ARP, entry_offset, off);
	if (ret)
		goto release_target;

	return 0;

release_target:
	module_put(t->u.kernel.target->me);
out:
	return ret;
}

Project: linux

static inline int check_entry_size_and_hooks(struct arpt_entry *e,
					     struct xt_table_info *newinfo,
					     const unsigned char *base,
					     const unsigned char *limit,
					     const unsigned int *hook_entries,
					     const unsigned int *underflows,
					     unsigned int valid_hooks)
{
	unsigned int h;
	int err;

	if ((unsigned long)e % __alignof__(struct arpt_entry) != 0 ||
	    (unsigned char *)e + sizeof(struct arpt_entry) >= limit ||
	    (unsigned char *)e + e->next_offset > limit)
		return -EINVAL;

	if (e->next_offset
	    < sizeof(struct arpt_entry) + sizeof(struct xt_entry_target))
		return -EINVAL;

	if (!arp_checkentry(&e->arp))
		return -EINVAL;

	err = xt_check_entry_offsets(e, e->elems, e->target_offset,
				     e->next_offset);
	if (err)
		return err;

	/* Check hooks & underflows */
	for (h = 0; h < NF_ARP_NUMHOOKS; h++) {
		if (!(valid_hooks & (1 << h)))
			continue;
		if ((unsigned char *)e - base == hook_entries[h])
			newinfo->hook_entry[h] = hook_entries[h];
		if ((unsigned char *)e - base == underflows[h]) {
			if (!check_underflow(e))
				return -EINVAL;

			newinfo->underflow[h] = underflows[h];
		}
	}

	/* Clear counters and comefrom */
	e->counters = ((struct xt_counters) { 0, 0 });
	e->comefrom = 0;
	return 0;
}

Project: linux

compat_copy_entry_from_user(struct compat_arpt_entry *e, void **dstptr,
			    unsigned int *size,
			    struct xt_table_info *newinfo, unsigned char *base)
{
	struct xt_entry_target *t;
	struct arpt_entry *de;
	unsigned int origsize;
	int h;

	origsize = *size;
	de = *dstptr;
	memcpy(de, e, sizeof(struct arpt_entry));
	memcpy(&de->counters, &e->counters, sizeof(e->counters));

	*dstptr += sizeof(struct arpt_entry);
	*size += sizeof(struct arpt_entry) - sizeof(struct compat_arpt_entry);

	de->target_offset = e->target_offset - (origsize - *size);
	t = compat_arpt_get_target(e);
	xt_compat_target_from_user(t, dstptr, size);

	de->next_offset = e->next_offset - (origsize - *size);
	for (h = 0; h < NF_ARP_NUMHOOKS; h++) {
		if ((unsigned char *)de - base < newinfo->hook_entry[h])
			newinfo->hook_entry[h] -= origsize - *size;
		if ((unsigned char *)de - base < newinfo->underflow[h])
			newinfo->underflow[h] -= origsize - *size;
	}
}

Project: linux

static int compat_copy_entry_to_user(struct arpt_entry *e, void __user **dstptr,
				     compat_uint_t *size,
				     struct xt_counters *counters,
				     unsigned int i)
{
	struct xt_entry_target *t;
	struct compat_arpt_entry __user *ce;
	u_int16_t target_offset, next_offset;
	compat_uint_t origsize;
	int ret;

	origsize = *size;
	ce = *dstptr;
	if (copy_to_user(ce, e, sizeof(struct arpt_entry)) != 0 ||
	    copy_to_user(&ce->counters, &counters[i],
	    sizeof(counters[i])) != 0)
		return -EFAULT;

	*dstptr += sizeof(struct compat_arpt_entry);
	*size -= sizeof(struct arpt_entry) - sizeof(struct compat_arpt_entry);

	target_offset = e->target_offset - (origsize - *size);

	t = arpt_get_target(e);
	ret = xt_compat_target_to_user(t, dstptr, size);
	if (ret)
		return ret;
	next_offset = e->next_offset - (origsize - *size);
	if (put_user(target_offset, &ce->target_offset) != 0 ||
	    put_user(next_offset, &ce->next_offset) != 0)
		return -EFAULT;
	return 0;
}

Project: linux

static int compat_do_arpt_set_ctl(struct sock *sk, int cmd, void __user *user,
				  unsigned int len)
{
	int ret;

	if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
		return -EPERM;

	switch (cmd) {
	case ARPT_SO_SET_REPLACE:
		ret = compat_do_replace(sock_net(sk), user, len);
		break;

	case ARPT_SO_SET_ADD_COUNTERS:
		ret = do_add_counters(sock_net(sk), user, len, 1);
		break;

	default:
		ret = -EINVAL;
	}

	return ret;
}

Project: linux

static int compat_do_replace(struct net *net, void __user *user,
			     unsigned int len)
{
	int ret;
	struct compat_arpt_replace tmp;
	struct xt_table_info *newinfo;
	void *loc_cpu_entry;
	struct arpt_entry *iter;

	if (copy_from_user(&tmp, user, sizeof(tmp)) != 0)
		return -EFAULT;

	/* overflow check */
	if (tmp.num_counters >= INT_MAX / sizeof(struct xt_counters))
		return -ENOMEM;
	if (tmp.num_counters == 0)
		return -EINVAL;

	tmp.name[sizeof(tmp.name)-1] = 0;

	newinfo = xt_alloc_table_info(tmp.size);
	if (!newinfo)
		return -ENOMEM;

	loc_cpu_entry = newinfo->entries;
	if (copy_from_user(loc_cpu_entry, user + sizeof(tmp), tmp.size) != 0) {
		ret = -EFAULT;
		goto free_newinfo;
	}

	ret = translate_compat_table(&newinfo, &loc_cpu_entry, &tmp);
	if (ret != 0)
		goto free_newinfo;

	ret = __do_replace(net, tmp.name, tmp.valid_hooks, newinfo,
			   tmp.num_counters, compat_ptr(tmp.counters));
	if (ret)
		goto free_newinfo_untrans;
	return 0;

 free_newinfo_untrans:
	xt_entry_foreach(iter, loc_cpu_entry, newinfo->size)
		cleanup_entry(iter);
 free_newinfo:
	xt_free_table_info(newinfo);
	return ret;
}

Project: linux

static int compat_get_entries(struct net *net,
			      struct compat_arpt_get_entries __user *uptr,
			      int *len)
{
	int ret;
	struct compat_arpt_get_entries get;
	struct xt_table *t;

	if (*len < sizeof(get))
		return -EINVAL;
	if (copy_from_user(&get, uptr, sizeof(get)) != 0)
		return -EFAULT;
	if (*len != sizeof(struct compat_arpt_get_entries) + get.size)
		return -EINVAL;

	get.name[sizeof(get.name) - 1] = '\0';

	xt_compat_lock(NFPROTO_ARP);
	t = xt_find_table_lock(net, NFPROTO_ARP, get.name);
	if (!IS_ERR(t)) {
		const struct xt_table_info *private = t->private;
		struct xt_table_info info;

		ret = compat_table_info(private, &info);
		if (!ret && get.size == info.size) {
			ret = compat_copy_entries_to_user(private->size,
							  t, uptr->entrytable);
		} else if (!ret)
			ret = -EAGAIN;

		xt_compat_flush_offsets(NFPROTO_ARP);
		module_put(t->me);
		xt_table_unlock(t);
	} else
		ret = PTR_ERR(t);

	xt_compat_unlock(NFPROTO_ARP);
	return ret;
}

Project: linux

static int copy_entries_to_user(unsigned int total_size,
				const struct xt_table *table,
				void __user *userptr)
{
	unsigned int off, num;
	const struct arpt_entry *e;
	struct xt_counters *counters;
	struct xt_table_info *private = table->private;
	int ret = 0;
	void *loc_cpu_entry;

	counters = alloc_counters(table);
	if (IS_ERR(counters))
		return PTR_ERR(counters);

	loc_cpu_entry = private->entries;

	/* FIXME: use iterator macros --RR */
	/* ... then go back and fix counters and names */
	for (off = 0, num = 0; off < total_size; off += e->next_offset, num++){
		const struct xt_entry_target *t;

		e = loc_cpu_entry + off;
		if (copy_to_user(userptr + off, e, sizeof(*e))) {
			ret = -EFAULT;
			goto free_counters;
		}
		if (copy_to_user(userptr + off
				 + offsetof(struct arpt_entry, counters),
				 &counters[num],
				 sizeof(counters[num])) != 0) {
			ret = -EFAULT;
			goto free_counters;
		}

		t = arpt_get_target_c(e);
		if (xt_target_to_user(t, userptr + off + e->target_offset)) {
			ret = -EFAULT;
			goto free_counters;
		}
	}

 free_counters:
	vfree(counters);
	return ret;
}

Project: linux

static int do_add_counters(struct net *net, const void __user *user,
			   unsigned int len, int compat)
{
	unsigned int i;
	struct xt_counters_info tmp;
	struct xt_counters *paddc;
	struct xt_table *t;
	const struct xt_table_info *private;
	int ret = 0;
	struct arpt_entry *iter;
	unsigned int addend;

	paddc = xt_copy_counters_from_user(user, len, &tmp, compat);
	if (IS_ERR(paddc))
		return PTR_ERR(paddc);

	t = xt_find_table_lock(net, NFPROTO_ARP, tmp.name);
	if (IS_ERR(t)) {
		ret = PTR_ERR(t);
		goto free;
	}

	local_bh_disable();
	private = t->private;
	if (private->number != tmp.num_counters) {
		ret = -EINVAL;
		goto unlock_up_free;
	}

	i = 0;

	addend = xt_write_recseq_begin();
	xt_entry_foreach(iter,  private->entries, private->size) {
		struct xt_counters *tmp;

		tmp = xt_get_this_cpu_counter(&iter->counters);
		ADD_COUNTER(*tmp, paddc[i].bcnt, paddc[i].pcnt);
		++i;
	}
	xt_write_recseq_end(addend);
 unlock_up_free:
	local_bh_enable();
	xt_table_unlock(t);
	module_put(t->me);
 free:
	vfree(paddc);

	return ret;
}

Project: linux

static int do_arpt_set_ctl(struct sock *sk, int cmd, void __user *user, unsigned int len)
{
	int ret;

	if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
		return -EPERM;

	switch (cmd) {
	case ARPT_SO_SET_REPLACE:
		ret = do_replace(sock_net(sk), user, len);
		break;

	case ARPT_SO_SET_ADD_COUNTERS:
		ret = do_add_counters(sock_net(sk), user, len, 0);
		break;

	default:
		ret = -EINVAL;
	}

	return ret;
}

Project: linux

static int do_replace(struct net *net, const void __user *user,
		      unsigned int len)
{
	int ret;
	struct arpt_replace tmp;
	struct xt_table_info *newinfo;
	void *loc_cpu_entry;
	struct arpt_entry *iter;

	if (copy_from_user(&tmp, user, sizeof(tmp)) != 0)
		return -EFAULT;

	/* overflow check */
	if (tmp.num_counters >= INT_MAX / sizeof(struct xt_counters))
		return -ENOMEM;
	if (tmp.num_counters == 0)
		return -EINVAL;

	tmp.name[sizeof(tmp.name)-1] = 0;

	newinfo = xt_alloc_table_info(tmp.size);
	if (!newinfo)
		return -ENOMEM;

	loc_cpu_entry = newinfo->entries;
	if (copy_from_user(loc_cpu_entry, user + sizeof(tmp),
			   tmp.size) != 0) {
		ret = -EFAULT;
		goto free_newinfo;
	}

	ret = translate_table(newinfo, loc_cpu_entry, &tmp);
	if (ret != 0)
		goto free_newinfo;

	ret = __do_replace(net, tmp.name, tmp.valid_hooks, newinfo,
			   tmp.num_counters, tmp.counters);
	if (ret)
		goto free_newinfo_untrans;
	return 0;

 free_newinfo_untrans:
	xt_entry_foreach(iter, loc_cpu_entry, newinfo->size)
		cleanup_entry(iter);
 free_newinfo:
	xt_free_table_info(newinfo);
	return ret;
}

Project: linux

find_check_entry(struct arpt_entry *e, const char *name, unsigned int size,
		 struct xt_percpu_counter_alloc_state *alloc_state)
{
	struct xt_entry_target *t;
	struct xt_target *target;
	int ret;

	if (!xt_percpu_counter_alloc(alloc_state, &e->counters))
		return -ENOMEM;

	t = arpt_get_target(e);
	target = xt_request_find_target(NFPROTO_ARP, t->u.user.name,
					t->u.user.revision);
	if (IS_ERR(target)) {
		ret = PTR_ERR(target);
		goto out;
	}
	t->u.kernel.target = target;

	ret = check_target(e, name);
	if (ret)
		goto err;
	return 0;
err:
	module_put(t->u.kernel.target->me);
out:
	xt_percpu_counter_free(&e->counters);

	return ret;
}

Project: linux

static void get_counters(const struct xt_table_info *t,
			 struct xt_counters counters[])
{
	struct arpt_entry *iter;
	unsigned int cpu;
	unsigned int i;

	for_each_possible_cpu(cpu) {
		seqcount_t *s = &per_cpu(xt_recseq, cpu);

		i = 0;
		xt_entry_foreach(iter, t->entries, t->size) {
			struct xt_counters *tmp;
			u64 bcnt, pcnt;
			unsigned int start;

			tmp = xt_get_per_cpu_counter(&iter->counters, cpu);
			do {
				start = read_seqcount_begin(s);
				bcnt = tmp->bcnt;
				pcnt = tmp->pcnt;
			} while (read_seqcount_retry(s, start));

			ADD_COUNTER(counters[i], bcnt, pcnt);
			++i;
			cond_resched();
		}
	}
}

Project: linux

static int get_entries(struct net *net, struct arpt_get_entries __user *uptr,
		       const int *len)
{
	int ret;
	struct arpt_get_entries get;
	struct xt_table *t;

	if (*len < sizeof(get))
		return -EINVAL;
	if (copy_from_user(&get, uptr, sizeof(get)) != 0)
		return -EFAULT;
	if (*len != sizeof(struct arpt_get_entries) + get.size)
		return -EINVAL;

	get.name[sizeof(get.name) - 1] = '\0';

	t = xt_find_table_lock(net, NFPROTO_ARP, get.name);
	if (!IS_ERR(t)) {
		const struct xt_table_info *private = t->private;

		if (get.size == private->size)
			ret = copy_entries_to_user(private->size,
						   t, uptr->entrytable);
		else
			ret = -EAGAIN;

		module_put(t->me);
		xt_table_unlock(t);
	} else
		ret = PTR_ERR(t);

	return ret;
}

Project: linux

static int get_info(struct net *net, void __user *user,
		    const int *len, int compat)
{
	char name[XT_TABLE_MAXNAMELEN];
	struct xt_table *t;
	int ret;

	if (*len != sizeof(struct arpt_getinfo))
		return -EINVAL;

	if (copy_from_user(name, user, sizeof(name)) != 0)
		return -EFAULT;

	name[XT_TABLE_MAXNAMELEN-1] = '\0';
#ifdef CONFIG_COMPAT
	if (compat)
		xt_compat_lock(NFPROTO_ARP);
#endif
	t = xt_request_find_table_lock(net, NFPROTO_ARP, name);
	if (!IS_ERR(t)) {
		struct arpt_getinfo info;
		const struct xt_table_info *private = t->private;
#ifdef CONFIG_COMPAT
		struct xt_table_info tmp;

		if (compat) {
			ret = compat_table_info(private, &tmp);
			xt_compat_flush_offsets(NFPROTO_ARP);
			private = &tmp;
		}
#endif
		memset(&info, 0, sizeof(info));
		info.valid_hooks = t->valid_hooks;
		memcpy(info.hook_entry, private->hook_entry,
		       sizeof(info.hook_entry));
		memcpy(info.underflow, private->underflow,
		       sizeof(info.underflow));
		info.num_entries = private->number;
		info.size = private->size;
		strcpy(info.name, name);

		if (copy_to_user(user, &info, *len) != 0)
			ret = -EFAULT;
		else
			ret = 0;
		xt_table_unlock(t);
		module_put(t->me);
	} else
		ret = PTR_ERR(t);
#ifdef CONFIG_COMPAT
	if (compat)
		xt_compat_unlock(NFPROTO_ARP);
#endif
	return ret;
}

Project: linux

static void get_old_counters(const struct xt_table_info *t,
			     struct xt_counters counters[])
{
	struct arpt_entry *iter;
	unsigned int cpu, i;

	for_each_possible_cpu(cpu) {
		i = 0;
		xt_entry_foreach(iter, t->entries, t->size) {
			struct xt_counters *tmp;

			tmp = xt_get_per_cpu_counter(&iter->counters, cpu);
			ADD_COUNTER(counters[i], tmp->bcnt, tmp->pcnt);
			++i;
		}
		cond_resched();
	}
}

Project: linux

static int mark_source_chains(const struct xt_table_info *newinfo,
			      unsigned int valid_hooks, void *entry0,
			      unsigned int *offsets)
{
	unsigned int hook;

	/* No recursion; use packet counter to save back ptrs (reset
	 * to 0 as we leave), and comefrom to save source hook bitmask.
	 */
	for (hook = 0; hook < NF_ARP_NUMHOOKS; hook++) {
		unsigned int pos = newinfo->hook_entry[hook];
		struct arpt_entry *e = entry0 + pos;

		if (!(valid_hooks & (1 << hook)))
			continue;

		/* Set initial back pointer. */
		e->counters.pcnt = pos;

		for (;;) {
			const struct xt_standard_target *t
				= (void *)arpt_get_target_c(e);
			int visited = e->comefrom & (1 << hook);

			if (e->comefrom & (1 << NF_ARP_NUMHOOKS))
				return 0;

			e->comefrom
				|= ((1 << hook) | (1 << NF_ARP_NUMHOOKS));

			/* Unconditional return/END. */
			if ((unconditional(e) &&
			     (strcmp(t->target.u.user.name,
				     XT_STANDARD_TARGET) == 0) &&
			     t->verdict < 0) || visited) {
				unsigned int oldpos, size;

				if ((strcmp(t->target.u.user.name,
					    XT_STANDARD_TARGET) == 0) &&
				    t->verdict < -NF_MAX_VERDICT - 1)
					return 0;

				/* Return: backtrack through the last
				 * big jump.
				 */
				do {
					e->comefrom ^= (1<<NF_ARP_NUMHOOKS);
					oldpos = pos;
					pos = e->counters.pcnt;
					e->counters.pcnt = 0;

					/* We're at the start. */
					if (pos == oldpos)
						goto next;

					e = entry0 + pos;
				} while (oldpos == pos + e->next_offset);

				/* Move along one */
				size = e->next_offset;
				e = entry0 + pos + size;
				if (pos + size >= newinfo->size)
					return 0;
				e->counters.pcnt = pos;
				pos += size;
			} else {
				int newpos = t->verdict;

				if (strcmp(t->target.u.user.name,
					   XT_STANDARD_TARGET) == 0 &&
				    newpos >= 0) {
					/* This a jump; chase it. */
					if (!xt_find_jump_offset(offsets, newpos,
								 newinfo->number))
						return 0;
				} else {
					/* ... this is a fallthru */
					newpos = pos + e->next_offset;
					if (newpos >= newinfo->size)
						return 0;
				}
				e = entry0 + newpos;
				e->counters.pcnt = pos;
				pos = newpos;
			}
		}
next:		;
	}
	return 1;
}

Project: linux

static int translate_compat_table(struct xt_table_info **pinfo,
				  void **pentry0,
				  const struct compat_arpt_replace *compatr)
{
	unsigned int i, j;
	struct xt_table_info *newinfo, *info;
	void *pos, *entry0, *entry1;
	struct compat_arpt_entry *iter0;
	struct arpt_replace repl;
	unsigned int size;
	int ret = 0;

	info = *pinfo;
	entry0 = *pentry0;
	size = compatr->size;
	info->number = compatr->num_entries;

	j = 0;
	xt_compat_lock(NFPROTO_ARP);
	xt_compat_init_offsets(NFPROTO_ARP, compatr->num_entries);
	/* Walk through entries, checking offsets. */
	xt_entry_foreach(iter0, entry0, compatr->size) {
		ret = check_compat_entry_size_and_hooks(iter0, info, &size,
							entry0,
							entry0 + compatr->size);
		if (ret != 0)
			goto out_unlock;
		++j;
	}

	ret = -EINVAL;
	if (j != compatr->num_entries)
		goto out_unlock;

	ret = -ENOMEM;
	newinfo = xt_alloc_table_info(size);
	if (!newinfo)
		goto out_unlock;

	newinfo->number = compatr->num_entries;
	for (i = 0; i < NF_ARP_NUMHOOKS; i++) {
		newinfo->hook_entry[i] = compatr->hook_entry[i];
		newinfo->underflow[i] = compatr->underflow[i];
	}
	entry1 = newinfo->entries;
	pos = entry1;
	size = compatr->size;
	xt_entry_foreach(iter0, entry0, compatr->size)
		compat_copy_entry_from_user(iter0, &pos, &size,
					    newinfo, entry1);

	/* all module references in entry0 are now gone */

	xt_compat_flush_offsets(NFPROTO_ARP);
	xt_compat_unlock(NFPROTO_ARP);

	memcpy(&repl, compatr, sizeof(*compatr));

	for (i = 0; i < NF_ARP_NUMHOOKS; i++) {
		repl.hook_entry[i] = newinfo->hook_entry[i];
		repl.underflow[i] = newinfo->underflow[i];
	}

	repl.num_counters = 0;
	repl.counters = NULL;
	repl.size = newinfo->size;
	ret = translate_table(newinfo, entry1, &repl);
	if (ret)
		goto free_newinfo;

	*pinfo = newinfo;
	*pentry0 = entry1;
	xt_free_table_info(info);
	return 0;

free_newinfo:
	xt_free_table_info(newinfo);
	return ret;
out_unlock:
	xt_compat_flush_offsets(NFPROTO_ARP);
	xt_compat_unlock(NFPROTO_ARP);
	xt_entry_foreach(iter0, entry0, compatr->size) {
		if (j-- == 0)
			break;
		compat_release_entry(iter0);
	}
	return ret;
}

Project: linux

static int translate_table(struct xt_table_info *newinfo, void *entry0,
			   const struct arpt_replace *repl)
{
	struct xt_percpu_counter_alloc_state alloc_state = { 0 };
	struct arpt_entry *iter;
	unsigned int *offsets;
	unsigned int i;
	int ret = 0;

	newinfo->size = repl->size;
	newinfo->number = repl->num_entries;

	/* Init all hooks to impossible value. */
	for (i = 0; i < NF_ARP_NUMHOOKS; i++) {
		newinfo->hook_entry[i] = 0xFFFFFFFF;
		newinfo->underflow[i] = 0xFFFFFFFF;
	}

	offsets = xt_alloc_entry_offsets(newinfo->number);
	if (!offsets)
		return -ENOMEM;
	i = 0;

	/* Walk through entries, checking offsets. */
	xt_entry_foreach(iter, entry0, newinfo->size) {
		ret = check_entry_size_and_hooks(iter, newinfo, entry0,
						 entry0 + repl->size,
						 repl->hook_entry,
						 repl->underflow,
						 repl->valid_hooks);
		if (ret != 0)
			goto out_free;
		if (i < repl->num_entries)
			offsets[i] = (void *)iter - entry0;
		++i;
		if (strcmp(arpt_get_target(iter)->u.user.name,
		    XT_ERROR_TARGET) == 0)
			++newinfo->stacksize;
	}

	ret = -EINVAL;
	if (i != repl->num_entries)
		goto out_free;

	/* Check hooks all assigned */
	for (i = 0; i < NF_ARP_NUMHOOKS; i++) {
		/* Only hooks which are valid */
		if (!(repl->valid_hooks & (1 << i)))
			continue;
		if (newinfo->hook_entry[i] == 0xFFFFFFFF)
			goto out_free;
		if (newinfo->underflow[i] == 0xFFFFFFFF)
			goto out_free;
	}

	if (!mark_source_chains(newinfo, repl->valid_hooks, entry0, offsets)) {
		ret = -ELOOP;
		goto out_free;
	}
	kvfree(offsets);

	/* Finally, each sanity check must pass */
	i = 0;
	xt_entry_foreach(iter, entry0, newinfo->size) {
		ret = find_check_entry(iter, repl->name, repl->size,
				       &alloc_state);
		if (ret != 0)
			break;
		++i;
	}

	if (ret != 0) {
		xt_entry_foreach(iter, entry0, newinfo->size) {
			if (i-- == 0)
				break;
			cleanup_entry(iter);
		}
		return ret;
	}

	return ret;
 out_free:
	kvfree(offsets);
	return ret;
}

Project: linux

check_compat_entry_size_and_hooks(struct compat_ipt_entry *e,
				  struct xt_table_info *newinfo,
				  unsigned int *size,
				  const unsigned char *base,
				  const unsigned char *limit)
{
	struct xt_entry_match *ematch;
	struct xt_entry_target *t;
	struct xt_target *target;
	unsigned int entry_offset;
	unsigned int j;
	int ret, off;

	if ((unsigned long)e % __alignof__(struct compat_ipt_entry) != 0 ||
	    (unsigned char *)e + sizeof(struct compat_ipt_entry) >= limit ||
	    (unsigned char *)e + e->next_offset > limit)
		return -EINVAL;

	if (e->next_offset < sizeof(struct compat_ipt_entry) +
			     sizeof(struct compat_xt_entry_target))
		return -EINVAL;

	if (!ip_checkentry(&e->ip))
		return -EINVAL;

	ret = xt_compat_check_entry_offsets(e, e->elems,
					    e->target_offset, e->next_offset);
	if (ret)
		return ret;

	off = sizeof(struct ipt_entry) - sizeof(struct compat_ipt_entry);
	entry_offset = (void *)e - (void *)base;
	j = 0;
	xt_ematch_foreach(ematch, e) {
		ret = compat_find_calc_match(ematch, &e->ip, &off);
		if (ret != 0)
			goto release_matches;
		++j;
	}

	t = compat_ipt_get_target(e);
	target = xt_request_find_target(NFPROTO_IPV4, t->u.user.name,
					t->u.user.revision);
	if (IS_ERR(target)) {
		ret = PTR_ERR(target);
		goto release_matches;
	}
	t->u.kernel.target = target;

	off += xt_compat_target_offset(target);
	*size += off;
	ret = xt_compat_add_offset(AF_INET, entry_offset, off);
	if (ret)
		goto out;

	return 0;

out:
	module_put(t->u.kernel.target->me);
release_matches:
	xt_ematch_foreach(ematch, e) {
		if (j-- == 0)
			break;
		module_put(ematch->u.kernel.match->me);
	}
	return ret;
}

Project: linux

check_entry_size_and_hooks(struct ipt_entry *e,
			   struct xt_table_info *newinfo,
			   const unsigned char *base,
			   const unsigned char *limit,
			   const unsigned int *hook_entries,
			   const unsigned int *underflows,
			   unsigned int valid_hooks)
{
	unsigned int h;
	int err;

	if ((unsigned long)e % __alignof__(struct ipt_entry) != 0 ||
	    (unsigned char *)e + sizeof(struct ipt_entry) >= limit ||
	    (unsigned char *)e + e->next_offset > limit)
		return -EINVAL;

	if (e->next_offset
	    < sizeof(struct ipt_entry) + sizeof(struct xt_entry_target))
		return -EINVAL;

	if (!ip_checkentry(&e->ip))
		return -EINVAL;

	err = xt_check_entry_offsets(e, e->elems, e->target_offset,
				     e->next_offset);
	if (err)
		return err;

	/* Check hooks & underflows */
	for (h = 0; h < NF_INET_NUMHOOKS; h++) {
		if (!(valid_hooks & (1 << h)))
			continue;
		if ((unsigned char *)e - base == hook_entries[h])
			newinfo->hook_entry[h] = hook_entries[h];
		if ((unsigned char *)e - base == underflows[h]) {
			if (!check_underflow(e))
				return -EINVAL;

			newinfo->underflow[h] = underflows[h];
		}
	}

	/* Clear counters and comefrom */
	e->counters = ((struct xt_counters) { 0, 0 });
	e->comefrom = 0;
	return 0;
}

Project: linux

check_match(struct xt_entry_match *m, struct xt_mtchk_param *par)
{
	const struct ipt_ip *ip = par->entryinfo;

	par->match     = m->u.kernel.match;
	par->matchinfo = m->data;

	return xt_check_match(par, m->u.match_size - sizeof(*m),
			      ip->proto, ip->invflags & IPT_INV_PROTO);
}

Project: linux

static int check_target(struct ipt_entry *e, struct net *net, const char *name)
{
	struct xt_entry_target *t = ipt_get_target(e);
	struct xt_tgchk_param par = {
		.net       = net,
		.table     = name,
		.entryinfo = e,
		.target    = t->u.kernel.target,
		.targinfo  = t->data,
		.hook_mask = e->comefrom,
		.family    = NFPROTO_IPV4,
	};

	return xt_check_target(&par, t->u.target_size - sizeof(*t),
			       e->ip.proto, e->ip.invflags & IPT_INV_PROTO);
}

Project: linux

cleanup_entry(struct ipt_entry *e, struct net *net)
{
	struct xt_tgdtor_param par;
	struct xt_entry_target *t;
	struct xt_entry_match *ematch;

	/* Cleanup all matches */
	xt_ematch_foreach(ematch, e)
		cleanup_match(ematch, net);
	t = ipt_get_target(e);

	par.net      = net;
	par.target   = t->u.kernel.target;
	par.targinfo = t->data;
	par.family   = NFPROTO_IPV4;
	if (par.target->destroy != NULL)
		par.target->destroy(&par);
	module_put(par.target->me);
	xt_percpu_counter_free(&e->counters);
}

Project: linux

compat_copy_entry_from_user(struct compat_ipt_entry *e, void **dstptr,
			    unsigned int *size,
			    struct xt_table_info *newinfo, unsigned char *base)
{
	struct xt_entry_target *t;
	struct ipt_entry *de;
	unsigned int origsize;
	int h;
	struct xt_entry_match *ematch;

	origsize = *size;
	de = *dstptr;
	memcpy(de, e, sizeof(struct ipt_entry));
	memcpy(&de->counters, &e->counters, sizeof(e->counters));

	*dstptr += sizeof(struct ipt_entry);
	*size += sizeof(struct ipt_entry) - sizeof(struct compat_ipt_entry);

	xt_ematch_foreach(ematch, e)
		xt_compat_match_from_user(ematch, dstptr, size);

	de->target_offset = e->target_offset - (origsize - *size);
	t = compat_ipt_get_target(e);
	xt_compat_target_from_user(t, dstptr, size);

	de->next_offset = e->next_offset - (origsize - *size);

	for (h = 0; h < NF_INET_NUMHOOKS; h++) {
		if ((unsigned char *)de - base < newinfo->hook_entry[h])
			newinfo->hook_entry[h] -= origsize - *size;
		if ((unsigned char *)de - base < newinfo->underflow[h])
			newinfo->underflow[h] -= origsize - *size;
	}
}

Project: linux

compat_copy_entry_to_user(struct ipt_entry *e, void __user **dstptr,
			  unsigned int *size, struct xt_counters *counters,
			  unsigned int i)
{
	struct xt_entry_target *t;
	struct compat_ipt_entry __user *ce;
	u_int16_t target_offset, next_offset;
	compat_uint_t origsize;
	const struct xt_entry_match *ematch;
	int ret = 0;

	origsize = *size;
	ce = *dstptr;
	if (copy_to_user(ce, e, sizeof(struct ipt_entry)) != 0 ||
	    copy_to_user(&ce->counters, &counters[i],
	    sizeof(counters[i])) != 0)
		return -EFAULT;

	*dstptr += sizeof(struct compat_ipt_entry);
	*size -= sizeof(struct ipt_entry) - sizeof(struct compat_ipt_entry);

	xt_ematch_foreach(ematch, e) {
		ret = xt_compat_match_to_user(ematch, dstptr, size);
		if (ret != 0)
			return ret;
	}
	target_offset = e->target_offset - (origsize - *size);
	t = ipt_get_target(e);
	ret = xt_compat_target_to_user(t, dstptr, size);
	if (ret)
		return ret;
	next_offset = e->next_offset - (origsize - *size);
	if (put_user(target_offset, &ce->target_offset) != 0 ||
	    put_user(next_offset, &ce->next_offset) != 0)
		return -EFAULT;
	return 0;
}

Project: linux

compat_do_ipt_set_ctl(struct sock *sk,	int cmd, void __user *user,
		      unsigned int len)
{
	int ret;

	if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
		return -EPERM;

	switch (cmd) {
	case IPT_SO_SET_REPLACE:
		ret = compat_do_replace(sock_net(sk), user, len);
		break;

	case IPT_SO_SET_ADD_COUNTERS:
		ret = do_add_counters(sock_net(sk), user, len, 1);
		break;

	default:
		ret = -EINVAL;
	}

	return ret;
}

Project: linux

compat_do_replace(struct net *net, void __user *user, unsigned int len)
{
	int ret;
	struct compat_ipt_replace tmp;
	struct xt_table_info *newinfo;
	void *loc_cpu_entry;
	struct ipt_entry *iter;

	if (copy_from_user(&tmp, user, sizeof(tmp)) != 0)
		return -EFAULT;

	/* overflow check */
	if (tmp.num_counters >= INT_MAX / sizeof(struct xt_counters))
		return -ENOMEM;
	if (tmp.num_counters == 0)
		return -EINVAL;

	tmp.name[sizeof(tmp.name)-1] = 0;

	newinfo = xt_alloc_table_info(tmp.size);
	if (!newinfo)
		return -ENOMEM;

	loc_cpu_entry = newinfo->entries;
	if (copy_from_user(loc_cpu_entry, user + sizeof(tmp),
			   tmp.size) != 0) {
		ret = -EFAULT;
		goto free_newinfo;
	}

	ret = translate_compat_table(net, &newinfo, &loc_cpu_entry, &tmp);
	if (ret != 0)
		goto free_newinfo;

	ret = __do_replace(net, tmp.name, tmp.valid_hooks, newinfo,
			   tmp.num_counters, compat_ptr(tmp.counters));
	if (ret)
		goto free_newinfo_untrans;
	return 0;

 free_newinfo_untrans:
	xt_entry_foreach(iter, loc_cpu_entry, newinfo->size)
		cleanup_entry(iter, net);
 free_newinfo:
	xt_free_table_info(newinfo);
	return ret;
}

Project: linux

compat_find_calc_match(struct xt_entry_match *m,
		       const struct ipt_ip *ip,
		       int *size)
{
	struct xt_match *match;

	match = xt_request_find_match(NFPROTO_IPV4, m->u.user.name,
				      m->u.user.revision);
	if (IS_ERR(match))
		return PTR_ERR(match);

	m->u.kernel.match = match;
	*size += xt_compat_match_offset(match);
	return 0;
}

Project: linux

do_add_counters(struct net *net, const void __user *user,
		unsigned int len, int compat)
{
	unsigned int i;
	struct xt_counters_info tmp;
	struct xt_counters *paddc;
	struct xt_table *t;
	const struct xt_table_info *private;
	int ret = 0;
	struct ipt_entry *iter;
	unsigned int addend;

	paddc = xt_copy_counters_from_user(user, len, &tmp, compat);
	if (IS_ERR(paddc))
		return PTR_ERR(paddc);

	t = xt_find_table_lock(net, AF_INET, tmp.name);
	if (IS_ERR(t)) {
		ret = PTR_ERR(t);
		goto free;
	}

	local_bh_disable();
	private = t->private;
	if (private->number != tmp.num_counters) {
		ret = -EINVAL;
		goto unlock_up_free;
	}

	i = 0;
	addend = xt_write_recseq_begin();
	xt_entry_foreach(iter, private->entries, private->size) {
		struct xt_counters *tmp;

		tmp = xt_get_this_cpu_counter(&iter->counters);
		ADD_COUNTER(*tmp, paddc[i].bcnt, paddc[i].pcnt);
		++i;
	}
	xt_write_recseq_end(addend);
 unlock_up_free:
	local_bh_enable();
	xt_table_unlock(t);
	module_put(t->me);
 free:
	vfree(paddc);

	return ret;
}

Project: linux

do_ipt_get_ctl(struct sock *sk, int cmd, void __user *user, int *len)
{
	int ret;

	if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
		return -EPERM;

	switch (cmd) {
	case IPT_SO_GET_INFO:
		ret = get_info(sock_net(sk), user, len, 0);
		break;

	case IPT_SO_GET_ENTRIES:
		ret = get_entries(sock_net(sk), user, len);
		break;

	case IPT_SO_GET_REVISION_MATCH:
	case IPT_SO_GET_REVISION_TARGET: {
		struct xt_get_revision rev;
		int target;

		if (*len != sizeof(rev)) {
			ret = -EINVAL;
			break;
		}
		if (copy_from_user(&rev, user, sizeof(rev)) != 0) {
			ret = -EFAULT;
			break;
		}
		rev.name[sizeof(rev.name)-1] = 0;

		if (cmd == IPT_SO_GET_REVISION_TARGET)
			target = 1;
		else
			target = 0;

		try_then_request_module(xt_find_revision(AF_INET, rev.name,
							 rev.revision,
							 target, &ret),
					"ipt_%s", rev.name);
		break;
	}

	default:
		ret = -EINVAL;
	}

	return ret;
}

Project: linux

do_ipt_set_ctl(struct sock *sk, int cmd, void __user *user, unsigned int len)
{
	int ret;

	if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
		return -EPERM;

	switch (cmd) {
	case IPT_SO_SET_REPLACE:
		ret = do_replace(sock_net(sk), user, len);
		break;

	case IPT_SO_SET_ADD_COUNTERS:
		ret = do_add_counters(sock_net(sk), user, len, 0);
		break;

	default:
		ret = -EINVAL;
	}

	return ret;
}

Project: linux

find_check_entry(struct ipt_entry *e, struct net *net, const char *name,
		 unsigned int size,
		 struct xt_percpu_counter_alloc_state *alloc_state)
{
	struct xt_entry_target *t;
	struct xt_target *target;
	int ret;
	unsigned int j;
	struct xt_mtchk_param mtpar;
	struct xt_entry_match *ematch;

	if (!xt_percpu_counter_alloc(alloc_state, &e->counters))
		return -ENOMEM;

	j = 0;
	mtpar.net	= net;
	mtpar.table     = name;
	mtpar.entryinfo = &e->ip;
	mtpar.hook_mask = e->comefrom;
	mtpar.family    = NFPROTO_IPV4;
	xt_ematch_foreach(ematch, e) {
		ret = find_check_match(ematch, &mtpar);
		if (ret != 0)
			goto cleanup_matches;
		++j;
	}

	t = ipt_get_target(e);
	target = xt_request_find_target(NFPROTO_IPV4, t->u.user.name,
					t->u.user.revision);
	if (IS_ERR(target)) {
		ret = PTR_ERR(target);
		goto cleanup_matches;
	}
	t->u.kernel.target = target;

	ret = check_target(e, net, name);
	if (ret)
		goto err;

	return 0;
 err:
	module_put(t->u.kernel.target->me);
 cleanup_matches:
	xt_ematch_foreach(ematch, e) {
		if (j-- == 0)
			break;
		cleanup_match(ematch, net);
	}

	xt_percpu_counter_free(&e->counters);

	return ret;
}

Project: linux

find_check_match(struct xt_entry_match *m, struct xt_mtchk_param *par)
{
	struct xt_match *match;
	int ret;

	match = xt_request_find_match(NFPROTO_IPV4, m->u.user.name,
				      m->u.user.revision);
	if (IS_ERR(match))
		return PTR_ERR(match);
	m->u.kernel.match = match;

	ret = check_match(m, par);
	if (ret)
		goto err;

	return 0;
err:
	module_put(m->u.kernel.match->me);
	return ret;
}

Project: linux

get_counters(const struct xt_table_info *t,
	     struct xt_counters counters[])
{
	struct ipt_entry *iter;
	unsigned int cpu;
	unsigned int i;

	for_each_possible_cpu(cpu) {
		seqcount_t *s = &per_cpu(xt_recseq, cpu);

		i = 0;
		xt_entry_foreach(iter, t->entries, t->size) {
			struct xt_counters *tmp;
			u64 bcnt, pcnt;
			unsigned int start;

			tmp = xt_get_per_cpu_counter(&iter->counters, cpu);
			do {
				start = read_seqcount_begin(s);
				bcnt = tmp->bcnt;
				pcnt = tmp->pcnt;
			} while (read_seqcount_retry(s, start));

			ADD_COUNTER(counters[i], bcnt, pcnt);
			++i; /* macro does multi eval of i */
			cond_resched();
		}
	}
}

Project: linux

get_entries(struct net *net, struct ipt_get_entries __user *uptr,
	    const int *len)
{
	int ret;
	struct ipt_get_entries get;
	struct xt_table *t;

	if (*len < sizeof(get))
		return -EINVAL;
	if (copy_from_user(&get, uptr, sizeof(get)) != 0)
		return -EFAULT;
	if (*len != sizeof(struct ipt_get_entries) + get.size)
		return -EINVAL;
	get.name[sizeof(get.name) - 1] = '\0';

	t = xt_find_table_lock(net, AF_INET, get.name);
	if (!IS_ERR(t)) {
		const struct xt_table_info *private = t->private;
		if (get.size == private->size)
			ret = copy_entries_to_user(private->size,
						   t, uptr->entrytable);
		else
			ret = -EAGAIN;

		module_put(t->me);
		xt_table_unlock(t);
	} else
		ret = PTR_ERR(t);

	return ret;
}

Project: linux

static int get_info(struct net *net, void __user *user,
		    const int *len, int compat)
{
	char name[XT_TABLE_MAXNAMELEN];
	struct xt_table *t;
	int ret;

	if (*len != sizeof(struct ipt_getinfo))
		return -EINVAL;

	if (copy_from_user(name, user, sizeof(name)) != 0)
		return -EFAULT;

	name[XT_TABLE_MAXNAMELEN-1] = '\0';
#ifdef CONFIG_COMPAT
	if (compat)
		xt_compat_lock(AF_INET);
#endif
	t = xt_request_find_table_lock(net, AF_INET, name);
	if (!IS_ERR(t)) {
		struct ipt_getinfo info;
		const struct xt_table_info *private = t->private;
#ifdef CONFIG_COMPAT
		struct xt_table_info tmp;

		if (compat) {
			ret = compat_table_info(private, &tmp);
			xt_compat_flush_offsets(AF_INET);
			private = &tmp;
		}
#endif
		memset(&info, 0, sizeof(info));
		info.valid_hooks = t->valid_hooks;
		memcpy(info.hook_entry, private->hook_entry,
		       sizeof(info.hook_entry));
		memcpy(info.underflow, private->underflow,
		       sizeof(info.underflow));
		info.num_entries = private->number;
		info.size = private->size;
		strcpy(info.name, name);

		if (copy_to_user(user, &info, *len) != 0)
			ret = -EFAULT;
		else
			ret = 0;

		xt_table_unlock(t);
		module_put(t->me);
	} else
		ret = PTR_ERR(t);
#ifdef CONFIG_COMPAT
	if (compat)
		xt_compat_unlock(AF_INET);
#endif
	return ret;
}

Project: linux

static void get_old_counters(const struct xt_table_info *t,
			     struct xt_counters counters[])
{
	struct ipt_entry *iter;
	unsigned int cpu, i;

	for_each_possible_cpu(cpu) {
		i = 0;
		xt_entry_foreach(iter, t->entries, t->size) {
			const struct xt_counters *tmp;

			tmp = xt_get_per_cpu_counter(&iter->counters, cpu);
			ADD_COUNTER(counters[i], tmp->bcnt, tmp->pcnt);
			++i; /* macro does multi eval of i */
		}

		cond_resched();
	}
}

Project: linux

ip_checkentry(const struct ipt_ip *ip)
{
	if (ip->flags & ~IPT_F_MASK)
		return false;
	if (ip->invflags & ~IPT_INV_MASK)
		return false;
	return true;
}

Project: linux

static int __init ip_tables_init(void)
{
	int ret;

	ret = register_pernet_subsys(&ip_tables_net_ops);
	if (ret < 0)
		goto err1;

	/* No one else will be downing sem now, so we won't sleep */
	ret = xt_register_targets(ipt_builtin_tg, ARRAY_SIZE(ipt_builtin_tg));
	if (ret < 0)
		goto err2;
	ret = xt_register_matches(ipt_builtin_mt, ARRAY_SIZE(ipt_builtin_mt));
	if (ret < 0)
		goto err4;

	/* Register setsockopt */
	ret = nf_register_sockopt(&ipt_sockopts);
	if (ret < 0)
		goto err5;

	return 0;

err5:
	xt_unregister_matches(ipt_builtin_mt, ARRAY_SIZE(ipt_builtin_mt));
err4:
	xt_unregister_targets(ipt_builtin_tg, ARRAY_SIZE(ipt_builtin_tg));
err2:
	unregister_pernet_subsys(&ip_tables_net_ops);
err1:
	return ret;
}

Project: linux

mark_source_chains(const struct xt_table_info *newinfo,
		   unsigned int valid_hooks, void *entry0,
		   unsigned int *offsets)
{
	unsigned int hook;

	/* No recursion; use packet counter to save back ptrs (reset
	   to 0 as we leave), and comefrom to save source hook bitmask */
	for (hook = 0; hook < NF_INET_NUMHOOKS; hook++) {
		unsigned int pos = newinfo->hook_entry[hook];
		struct ipt_entry *e = entry0 + pos;

		if (!(valid_hooks & (1 << hook)))
			continue;

		/* Set initial back pointer. */
		e->counters.pcnt = pos;

		for (;;) {
			const struct xt_standard_target *t
				= (void *)ipt_get_target_c(e);
			int visited = e->comefrom & (1 << hook);

			if (e->comefrom & (1 << NF_INET_NUMHOOKS))
				return 0;

			e->comefrom |= ((1 << hook) | (1 << NF_INET_NUMHOOKS));

			/* Unconditional return/END. */
			if ((unconditional(e) &&
			     (strcmp(t->target.u.user.name,
				     XT_STANDARD_TARGET) == 0) &&
			     t->verdict < 0) || visited) {
				unsigned int oldpos, size;

				if ((strcmp(t->target.u.user.name,
					    XT_STANDARD_TARGET) == 0) &&
				    t->verdict < -NF_MAX_VERDICT - 1)
					return 0;

				/* Return: backtrack through the last
				   big jump. */
				do {
					e->comefrom ^= (1<<NF_INET_NUMHOOKS);
					oldpos = pos;
					pos = e->counters.pcnt;
					e->counters.pcnt = 0;

					/* We're at the start. */
					if (pos == oldpos)
						goto next;

					e = entry0 + pos;
				} while (oldpos == pos + e->next_offset);

				/* Move along one */
				size = e->next_offset;
				e = entry0 + pos + size;
				if (pos + size >= newinfo->size)
					return 0;
				e->counters.pcnt = pos;
				pos += size;
			} else {
				int newpos = t->verdict;

				if (strcmp(t->target.u.user.name,
					   XT_STANDARD_TARGET) == 0 &&
				    newpos >= 0) {
					/* This a jump; chase it. */
					if (!xt_find_jump_offset(offsets, newpos,
								 newinfo->number))
						return 0;
				} else {
					/* ... this is a fallthru */
					newpos = pos + e->next_offset;
					if (newpos >= newinfo->size)
						return 0;
				}
				e = entry0 + newpos;
				e->counters.pcnt = pos;
				pos = newpos;
			}
		}
next:		;
	}
	return 1;
}

Project: linux

translate_compat_table(struct net *net,
		       struct xt_table_info **pinfo,
		       void **pentry0,
		       const struct compat_ipt_replace *compatr)
{
	unsigned int i, j;
	struct xt_table_info *newinfo, *info;
	void *pos, *entry0, *entry1;
	struct compat_ipt_entry *iter0;
	struct ipt_replace repl;
	unsigned int size;
	int ret;

	info = *pinfo;
	entry0 = *pentry0;
	size = compatr->size;
	info->number = compatr->num_entries;

	j = 0;
	xt_compat_lock(AF_INET);
	xt_compat_init_offsets(AF_INET, compatr->num_entries);
	/* Walk through entries, checking offsets. */
	xt_entry_foreach(iter0, entry0, compatr->size) {
		ret = check_compat_entry_size_and_hooks(iter0, info, &size,
							entry0,
							entry0 + compatr->size);
		if (ret != 0)
			goto out_unlock;
		++j;
	}

	ret = -EINVAL;
	if (j != compatr->num_entries)
		goto out_unlock;

	ret = -ENOMEM;
	newinfo = xt_alloc_table_info(size);
	if (!newinfo)
		goto out_unlock;

	newinfo->number = compatr->num_entries;
	for (i = 0; i < NF_INET_NUMHOOKS; i++) {
		newinfo->hook_entry[i] = compatr->hook_entry[i];
		newinfo->underflow[i] = compatr->underflow[i];
	}
	entry1 = newinfo->entries;
	pos = entry1;
	size = compatr->size;
	xt_entry_foreach(iter0, entry0, compatr->size)
		compat_copy_entry_from_user(iter0, &pos, &size,
					    newinfo, entry1);

	/* all module references in entry0 are now gone.
	 * entry1/newinfo contains a 64bit ruleset that looks exactly as
	 * generated by 64bit userspace.
	 *
	 * Call standard translate_table() to validate all hook_entrys,
	 * underflows, check for loops, etc.
	 */
	xt_compat_flush_offsets(AF_INET);
	xt_compat_unlock(AF_INET);

	memcpy(&repl, compatr, sizeof(*compatr));

	for (i = 0; i < NF_INET_NUMHOOKS; i++) {
		repl.hook_entry[i] = newinfo->hook_entry[i];
		repl.underflow[i] = newinfo->underflow[i];
	}

	repl.num_counters = 0;
	repl.counters = NULL;
	repl.size = newinfo->size;
	ret = translate_table(net, newinfo, entry1, &repl);
	if (ret)
		goto free_newinfo;

	*pinfo = newinfo;
	*pentry0 = entry1;
	xt_free_table_info(info);
	return 0;

free_newinfo:
	xt_free_table_info(newinfo);
	return ret;
out_unlock:
	xt_compat_flush_offsets(AF_INET);
	xt_compat_unlock(AF_INET);
	xt_entry_foreach(iter0, entry0, compatr->size) {
		if (j-- == 0)
			break;
		compat_release_entry(iter0);
	}
	return ret;
}

Project: linux

translate_table(struct net *net, struct xt_table_info *newinfo, void *entry0,
		const struct ipt_replace *repl)
{
	struct xt_percpu_counter_alloc_state alloc_state = { 0 };
	struct ipt_entry *iter;
	unsigned int *offsets;
	unsigned int i;
	int ret = 0;

	newinfo->size = repl->size;
	newinfo->number = repl->num_entries;

	/* Init all hooks to impossible value. */
	for (i = 0; i < NF_INET_NUMHOOKS; i++) {
		newinfo->hook_entry[i] = 0xFFFFFFFF;
		newinfo->underflow[i] = 0xFFFFFFFF;
	}

	offsets = xt_alloc_entry_offsets(newinfo->number);
	if (!offsets)
		return -ENOMEM;
	i = 0;
	/* Walk through entries, checking offsets. */
	xt_entry_foreach(iter, entry0, newinfo->size) {
		ret = check_entry_size_and_hooks(iter, newinfo, entry0,
						 entry0 + repl->size,
						 repl->hook_entry,
						 repl->underflow,
						 repl->valid_hooks);
		if (ret != 0)
			goto out_free;
		if (i < repl->num_entries)
			offsets[i] = (void *)iter - entry0;
		++i;
		if (strcmp(ipt_get_target(iter)->u.user.name,
		    XT_ERROR_TARGET) == 0)
			++newinfo->stacksize;
	}

	ret = -EINVAL;
	if (i != repl->num_entries)
		goto out_free;

	/* Check hooks all assigned */
	for (i = 0; i < NF_INET_NUMHOOKS; i++) {
		/* Only hooks which are valid */
		if (!(repl->valid_hooks & (1 << i)))
			continue;
		if (newinfo->hook_entry[i] == 0xFFFFFFFF)
			goto out_free;
		if (newinfo->underflow[i] == 0xFFFFFFFF)
			goto out_free;
	}

	if (!mark_source_chains(newinfo, repl->valid_hooks, entry0, offsets)) {
		ret = -ELOOP;
		goto out_free;
	}
	kvfree(offsets);

	/* Finally, each sanity check must pass */
	i = 0;
	xt_entry_foreach(iter, entry0, newinfo->size) {
		ret = find_check_entry(iter, net, repl->name, repl->size,
				       &alloc_state);
		if (ret != 0)
			break;
		++i;
	}

	if (ret != 0) {
		xt_entry_foreach(iter, entry0, newinfo->size) {
			if (i-- == 0)
				break;
			cleanup_entry(iter, net);
		}
		return ret;
	}

	return ret;
 out_free:
	kvfree(offsets);
	return ret;
}

Project: linux

static inline bool unconditional(const struct ipt_entry *e)
{
	static const struct ipt_ip uncond;

	return e->target_offset == sizeof(struct ipt_entry) &&
	       memcmp(&e->ip, &uncond, sizeof(uncond)) == 0;
}

Project: linux

__do_replace(struct net *net, const char *name, unsigned int valid_hooks,
	     struct xt_table_info *newinfo, unsigned int num_counters,
	     void __user *counters_ptr)
{
	int ret;
	struct xt_table *t;
	struct xt_table_info *oldinfo;
	struct xt_counters *counters;
	struct ip6t_entry *iter;

	ret = 0;
	counters = vzalloc(num_counters * sizeof(struct xt_counters));
	if (!counters) {
		ret = -ENOMEM;
		goto out;
	}

	t = xt_request_find_table_lock(net, AF_INET6, name);
	if (IS_ERR(t)) {
		ret = PTR_ERR(t);
		goto free_newinfo_counters_untrans;
	}

	/* You lied! */
	if (valid_hooks != t->valid_hooks) {
		ret = -EINVAL;
		goto put_module;
	}

	oldinfo = xt_replace_table(t, num_counters, newinfo, &ret);
	if (!oldinfo)
		goto put_module;

	/* Update module usage count based on number of rules */
	if ((oldinfo->number > oldinfo->initial_entries) ||
	    (newinfo->number <= oldinfo->initial_entries))
		module_put(t->me);
	if ((oldinfo->number > oldinfo->initial_entries) &&
	    (newinfo->number <= oldinfo->initial_entries))
		module_put(t->me);

	get_old_counters(oldinfo, counters);

	/* Decrease module usage counts and free resource */
	xt_entry_foreach(iter, oldinfo->entries, oldinfo->size)
		cleanup_entry(iter, net);

	xt_free_table_info(oldinfo);
	if (copy_to_user(counters_ptr, counters,
			 sizeof(struct xt_counters) * num_counters) != 0) {
		/* Silent error, can't fail, new table is already in place */
		net_warn_ratelimited("ip6tables: counters copy to user failed while replacing table\n");
	}
	vfree(counters);
	xt_table_unlock(t);
	return ret;

 put_module:
	module_put(t->me);
	xt_table_unlock(t);
 free_newinfo_counters_untrans:
	vfree(counters);
 out:
	return ret;
}

Project: linux

check_compat_entry_size_and_hooks(struct compat_ip6t_entry *e,
				  struct xt_table_info *newinfo,
				  unsigned int *size,
				  const unsigned char *base,
				  const unsigned char *limit)
{
	struct xt_entry_match *ematch;
	struct xt_entry_target *t;
	struct xt_target *target;
	unsigned int entry_offset;
	unsigned int j;
	int ret, off;

	if ((unsigned long)e % __alignof__(struct compat_ip6t_entry) != 0 ||
	    (unsigned char *)e + sizeof(struct compat_ip6t_entry) >= limit ||
	    (unsigned char *)e + e->next_offset > limit)
		return -EINVAL;

	if (e->next_offset < sizeof(struct compat_ip6t_entry) +
			     sizeof(struct compat_xt_entry_target))
		return -EINVAL;

	if (!ip6_checkentry(&e->ipv6))
		return -EINVAL;

	ret = xt_compat_check_entry_offsets(e, e->elems,
					    e->target_offset, e->next_offset);
	if (ret)
		return ret;

	off = sizeof(struct ip6t_entry) - sizeof(struct compat_ip6t_entry);
	entry_offset = (void *)e - (void *)base;
	j = 0;
	xt_ematch_foreach(ematch, e) {
		ret = compat_find_calc_match(ematch, &e->ipv6, &off);
		if (ret != 0)
			goto release_matches;
		++j;
	}

	t = compat_ip6t_get_target(e);
	target = xt_request_find_target(NFPROTO_IPV6, t->u.user.name,
					t->u.user.revision);
	if (IS_ERR(target)) {
		ret = PTR_ERR(target);
		goto release_matches;
	}
	t->u.kernel.target = target;

	off += xt_compat_target_offset(target);
	*size += off;
	ret = xt_compat_add_offset(AF_INET6, entry_offset, off);
	if (ret)
		goto out;

	return 0;

out:
	module_put(t->u.kernel.target->me);
release_matches:
	xt_ematch_foreach(ematch, e) {
		if (j-- == 0)
			break;
		module_put(ematch->u.kernel.match->me);
	}
	return ret;
}

Project: linux

static int check_match(struct xt_entry_match *m, struct xt_mtchk_param *par)
{
	const struct ip6t_ip6 *ipv6 = par->entryinfo;

	par->match     = m->u.kernel.match;
	par->matchinfo = m->data;

	return xt_check_match(par, m->u.match_size - sizeof(*m),
			      ipv6->proto, ipv6->invflags & IP6T_INV_PROTO);
}

Project: linux

static int check_target(struct ip6t_entry *e, struct net *net, const char *name)
{
	struct xt_entry_target *t = ip6t_get_target(e);
	struct xt_tgchk_param par = {
		.net       = net,
		.table     = name,
		.entryinfo = e,
		.target    = t->u.kernel.target,
		.targinfo  = t->data,
		.hook_mask = e->comefrom,
		.family    = NFPROTO_IPV6,
	};

	t = ip6t_get_target(e);
	return xt_check_target(&par, t->u.target_size - sizeof(*t),
			       e->ipv6.proto,
			       e->ipv6.invflags & IP6T_INV_PROTO);
}

Project: linux

compat_copy_entry_from_user(struct compat_ip6t_entry *e, void **dstptr,
			    unsigned int *size,
			    struct xt_table_info *newinfo, unsigned char *base)
{
	struct xt_entry_target *t;
	struct ip6t_entry *de;
	unsigned int origsize;
	int h;
	struct xt_entry_match *ematch;

	origsize = *size;
	de = *dstptr;
	memcpy(de, e, sizeof(struct ip6t_entry));
	memcpy(&de->counters, &e->counters, sizeof(e->counters));

	*dstptr += sizeof(struct ip6t_entry);
	*size += sizeof(struct ip6t_entry) - sizeof(struct compat_ip6t_entry);

	xt_ematch_foreach(ematch, e)
		xt_compat_match_from_user(ematch, dstptr, size);

	de->target_offset = e->target_offset - (origsize - *size);
	t = compat_ip6t_get_target(e);
	xt_compat_target_from_user(t, dstptr, size);

	de->next_offset = e->next_offset - (origsize - *size);
	for (h = 0; h < NF_INET_NUMHOOKS; h++) {
		if ((unsigned char *)de - base < newinfo->hook_entry[h])
			newinfo->hook_entry[h] -= origsize - *size;
		if ((unsigned char *)de - base < newinfo->underflow[h])
			newinfo->underflow[h] -= origsize - *size;
	}
}

Project: linux

compat_copy_entry_to_user(struct ip6t_entry *e, void __user **dstptr,
			  unsigned int *size, struct xt_counters *counters,
			  unsigned int i)
{
	struct xt_entry_target *t;
	struct compat_ip6t_entry __user *ce;
	u_int16_t target_offset, next_offset;
	compat_uint_t origsize;
	const struct xt_entry_match *ematch;
	int ret = 0;

	origsize = *size;
	ce = *dstptr;
	if (copy_to_user(ce, e, sizeof(struct ip6t_entry)) != 0 ||
	    copy_to_user(&ce->counters, &counters[i],
	    sizeof(counters[i])) != 0)
		return -EFAULT;

	*dstptr += sizeof(struct compat_ip6t_entry);
	*size -= sizeof(struct ip6t_entry) - sizeof(struct compat_ip6t_entry);

	xt_ematch_foreach(ematch, e) {
		ret = xt_compat_match_to_user(ematch, dstptr, size);
		if (ret != 0)
			return ret;
	}
	target_offset = e->target_offset - (origsize - *size);
	t = ip6t_get_target(e);
	ret = xt_compat_target_to_user(t, dstptr, size);
	if (ret)
		return ret;
	next_offset = e->next_offset - (origsize - *size);
	if (put_user(target_offset, &ce->target_offset) != 0 ||
	    put_user(next_offset, &ce->next_offset) != 0)
		return -EFAULT;
	return 0;
}

Project: linux

compat_do_ip6t_set_ctl(struct sock *sk, int cmd, void __user *user,
		       unsigned int len)
{
	int ret;

	if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
		return -EPERM;

	switch (cmd) {
	case IP6T_SO_SET_REPLACE:
		ret = compat_do_replace(sock_net(sk), user, len);
		break;

	case IP6T_SO_SET_ADD_COUNTERS:
		ret = do_add_counters(sock_net(sk), user, len, 1);
		break;

	default:
		ret = -EINVAL;
	}

	return ret;
}

Project: linux

compat_do_replace(struct net *net, void __user *user, unsigned int len)
{
	int ret;
	struct compat_ip6t_replace tmp;
	struct xt_table_info *newinfo;
	void *loc_cpu_entry;
	struct ip6t_entry *iter;

	if (copy_from_user(&tmp, user, sizeof(tmp)) != 0)
		return -EFAULT;

	/* overflow check */
	if (tmp.num_counters >= INT_MAX / sizeof(struct xt_counters))
		return -ENOMEM;
	if (tmp.num_counters == 0)
		return -EINVAL;

	tmp.name[sizeof(tmp.name)-1] = 0;

	newinfo = xt_alloc_table_info(tmp.size);
	if (!newinfo)
		return -ENOMEM;

	loc_cpu_entry = newinfo->entries;
	if (copy_from_user(loc_cpu_entry, user + sizeof(tmp),
			   tmp.size) != 0) {
		ret = -EFAULT;
		goto free_newinfo;
	}

	ret = translate_compat_table(net, &newinfo, &loc_cpu_entry, &tmp);
	if (ret != 0)
		goto free_newinfo;

	ret = __do_replace(net, tmp.name, tmp.valid_hooks, newinfo,
			   tmp.num_counters, compat_ptr(tmp.counters));
	if (ret)
		goto free_newinfo_untrans;
	return 0;

 free_newinfo_untrans:
	xt_entry_foreach(iter, loc_cpu_entry, newinfo->size)
		cleanup_entry(iter, net);
 free_newinfo:
	xt_free_table_info(newinfo);
	return ret;
}

Project: linux

compat_find_calc_match(struct xt_entry_match *m,
		       const struct ip6t_ip6 *ipv6,
		       int *size)
{
	struct xt_match *match;

	match = xt_request_find_match(NFPROTO_IPV6, m->u.user.name,
				      m->u.user.revision);
	if (IS_ERR(match))
		return PTR_ERR(match);

	m->u.kernel.match = match;
	*size += xt_compat_match_offset(match);
	return 0;
}

Project: linux

compat_get_entries(struct net *net, struct compat_ip6t_get_entries __user *uptr,
		   int *len)
{
	int ret;
	struct compat_ip6t_get_entries get;
	struct xt_table *t;

	if (*len < sizeof(get))
		return -EINVAL;

	if (copy_from_user(&get, uptr, sizeof(get)) != 0)
		return -EFAULT;

	if (*len != sizeof(struct compat_ip6t_get_entries) + get.size)
		return -EINVAL;

	get.name[sizeof(get.name) - 1] = '\0';

	xt_compat_lock(AF_INET6);
	t = xt_find_table_lock(net, AF_INET6, get.name);
	if (!IS_ERR(t)) {
		const struct xt_table_info *private = t->private;
		struct xt_table_info info;
		ret = compat_table_info(private, &info);
		if (!ret && get.size == info.size)
			ret = compat_copy_entries_to_user(private->size,
							  t, uptr->entrytable);
		else if (!ret)
			ret = -EAGAIN;

		xt_compat_flush_offsets(AF_INET6);
		module_put(t->me);
		xt_table_unlock(t);
	} else
		ret = PTR_ERR(t);

	xt_compat_unlock(AF_INET6);
	return ret;
}

Project: linux

copy_entries_to_user(unsigned int total_size,
		     const struct xt_table *table,
		     void __user *userptr)
{
	unsigned int off, num;
	const struct ip6t_entry *e;
	struct xt_counters *counters;
	const struct xt_table_info *private = table->private;
	int ret = 0;
	const void *loc_cpu_entry;

	counters = alloc_counters(table);
	if (IS_ERR(counters))
		return PTR_ERR(counters);

	loc_cpu_entry = private->entries;

	/* FIXME: use iterator macros --RR */
	/* ... then go back and fix counters and names */
	for (off = 0, num = 0; off < total_size; off += e->next_offset, num++){
		unsigned int i;
		const struct xt_entry_match *m;
		const struct xt_entry_target *t;

		e = loc_cpu_entry + off;
		if (copy_to_user(userptr + off, e, sizeof(*e))) {
			ret = -EFAULT;
			goto free_counters;
		}
		if (copy_to_user(userptr + off
				 + offsetof(struct ip6t_entry, counters),
				 &counters[num],
				 sizeof(counters[num])) != 0) {
			ret = -EFAULT;
			goto free_counters;
		}

		for (i = sizeof(struct ip6t_entry);
		     i < e->target_offset;
		     i += m->u.match_size) {
			m = (void *)e + i;

			if (xt_match_to_user(m, userptr + off + i)) {
				ret = -EFAULT;
				goto free_counters;
			}
		}

		t = ip6t_get_target_c(e);
		if (xt_target_to_user(t, userptr + off + e->target_offset)) {
			ret = -EFAULT;
			goto free_counters;
		}
	}

 free_counters:
	vfree(counters);
	return ret;
}

Project: linux

do_add_counters(struct net *net, const void __user *user, unsigned int len,
		int compat)
{
	unsigned int i;
	struct xt_counters_info tmp;
	struct xt_counters *paddc;
	struct xt_table *t;
	const struct xt_table_info *private;
	int ret = 0;
	struct ip6t_entry *iter;
	unsigned int addend;

	paddc = xt_copy_counters_from_user(user, len, &tmp, compat);
	if (IS_ERR(paddc))
		return PTR_ERR(paddc);
	t = xt_find_table_lock(net, AF_INET6, tmp.name);
	if (IS_ERR(t)) {
		ret = PTR_ERR(t);
		goto free;
	}

	local_bh_disable();
	private = t->private;
	if (private->number != tmp.num_counters) {
		ret = -EINVAL;
		goto unlock_up_free;
	}

	i = 0;
	addend = xt_write_recseq_begin();
	xt_entry_foreach(iter, private->entries, private->size) {
		struct xt_counters *tmp;

		tmp = xt_get_this_cpu_counter(&iter->counters);
		ADD_COUNTER(*tmp, paddc[i].bcnt, paddc[i].pcnt);
		++i;
	}
	xt_write_recseq_end(addend);
 unlock_up_free:
	local_bh_enable();
	xt_table_unlock(t);
	module_put(t->me);
 free:
	vfree(paddc);

	return ret;
}

Project: linux

do_ip6t_get_ctl(struct sock *sk, int cmd, void __user *user, int *len)
{
	int ret;

	if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
		return -EPERM;

	switch (cmd) {
	case IP6T_SO_GET_INFO:
		ret = get_info(sock_net(sk), user, len, 0);
		break;

	case IP6T_SO_GET_ENTRIES:
		ret = get_entries(sock_net(sk), user, len);
		break;

	case IP6T_SO_GET_REVISION_MATCH:
	case IP6T_SO_GET_REVISION_TARGET: {
		struct xt_get_revision rev;
		int target;

		if (*len != sizeof(rev)) {
			ret = -EINVAL;
			break;
		}
		if (copy_from_user(&rev, user, sizeof(rev)) != 0) {
			ret = -EFAULT;
			break;
		}
		rev.name[sizeof(rev.name)-1] = 0;

		if (cmd == IP6T_SO_GET_REVISION_TARGET)
			target = 1;
		else
			target = 0;

		try_then_request_module(xt_find_revision(AF_INET6, rev.name,
							 rev.revision,
							 target, &ret),
					"ip6t_%s", rev.name);
		break;
	}

	default:
		ret = -EINVAL;
	}

	return ret;
}

Project: linux

do_ip6t_set_ctl(struct sock *sk, int cmd, void __user *user, unsigned int len)
{
	int ret;

	if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
		return -EPERM;

	switch (cmd) {
	case IP6T_SO_SET_REPLACE:
		ret = do_replace(sock_net(sk), user, len);
		break;

	case IP6T_SO_SET_ADD_COUNTERS:
		ret = do_add_counters(sock_net(sk), user, len, 0);
		break;

	default:
		ret = -EINVAL;
	}

	return ret;
}

Project: linux

do_replace(struct net *net, const void __user *user, unsigned int len)
{
	int ret;
	struct ip6t_replace tmp;
	struct xt_table_info *newinfo;
	void *loc_cpu_entry;
	struct ip6t_entry *iter;

	if (copy_from_user(&tmp, user, sizeof(tmp)) != 0)
		return -EFAULT;

	/* overflow check */
	if (tmp.num_counters >= INT_MAX / sizeof(struct xt_counters))
		return -ENOMEM;
	if (tmp.num_counters == 0)
		return -EINVAL;

	tmp.name[sizeof(tmp.name)-1] = 0;

	newinfo = xt_alloc_table_info(tmp.size);
	if (!newinfo)
		return -ENOMEM;

	loc_cpu_entry = newinfo->entries;
	if (copy_from_user(loc_cpu_entry, user + sizeof(tmp),
			   tmp.size) != 0) {
		ret = -EFAULT;
		goto free_newinfo;
	}

	ret = translate_table(net, newinfo, loc_cpu_entry, &tmp);
	if (ret != 0)
		goto free_newinfo;

	ret = __do_replace(net, tmp.name, tmp.valid_hooks, newinfo,
			   tmp.num_counters, tmp.counters);
	if (ret)
		goto free_newinfo_untrans;
	return 0;

 free_newinfo_untrans:
	xt_entry_foreach(iter, loc_cpu_entry, newinfo->size)
		cleanup_entry(iter, net);
 free_newinfo:
	xt_free_table_info(newinfo);
	return ret;
}

Project: linux

find_check_entry(struct ip6t_entry *e, struct net *net, const char *name,
		 unsigned int size,
		 struct xt_percpu_counter_alloc_state *alloc_state)
{
	struct xt_entry_target *t;
	struct xt_target *target;
	int ret;
	unsigned int j;
	struct xt_mtchk_param mtpar;
	struct xt_entry_match *ematch;

	if (!xt_percpu_counter_alloc(alloc_state, &e->counters))
		return -ENOMEM;

	j = 0;
	mtpar.net	= net;
	mtpar.table     = name;
	mtpar.entryinfo = &e->ipv6;
	mtpar.hook_mask = e->comefrom;
	mtpar.family    = NFPROTO_IPV6;
	xt_ematch_foreach(ematch, e) {
		ret = find_check_match(ematch, &mtpar);
		if (ret != 0)
			goto cleanup_matches;
		++j;
	}

	t = ip6t_get_target(e);
	target = xt_request_find_target(NFPROTO_IPV6, t->u.user.name,
					t->u.user.revision);
	if (IS_ERR(target)) {
		ret = PTR_ERR(target);
		goto cleanup_matches;
	}
	t->u.kernel.target = target;

	ret = check_target(e, net, name);
	if (ret)
		goto err;
	return 0;
 err:
	module_put(t->u.kernel.target->me);
 cleanup_matches:
	xt_ematch_foreach(ematch, e) {
		if (j-- == 0)
			break;
		cleanup_match(ematch, net);
	}

	xt_percpu_counter_free(&e->counters);

	return ret;
}

Project: linux

find_check_match(struct xt_entry_match *m, struct xt_mtchk_param *par)
{
	struct xt_match *match;
	int ret;

	match = xt_request_find_match(NFPROTO_IPV6, m->u.user.name,
				      m->u.user.revision);
	if (IS_ERR(match))
		return PTR_ERR(match);

	m->u.kernel.match = match;

	ret = check_match(m, par);
	if (ret)
		goto err;

	return 0;
err:
	module_put(m->u.kernel.match->me);
	return ret;
}

Project: linux

get_counters(const struct xt_table_info *t,
	     struct xt_counters counters[])
{
	struct ip6t_entry *iter;
	unsigned int cpu;
	unsigned int i;

	for_each_possible_cpu(cpu) {
		seqcount_t *s = &per_cpu(xt_recseq, cpu);

		i = 0;
		xt_entry_foreach(iter, t->entries, t->size) {
			struct xt_counters *tmp;
			u64 bcnt, pcnt;
			unsigned int start;

			tmp = xt_get_per_cpu_counter(&iter->counters, cpu);
			do {
				start = read_seqcount_begin(s);
				bcnt = tmp->bcnt;
				pcnt = tmp->pcnt;
			} while (read_seqcount_retry(s, start));

			ADD_COUNTER(counters[i], bcnt, pcnt);
			++i;
			cond_resched();
		}
	}
}

Project: linux

get_entries(struct net *net, struct ip6t_get_entries __user *uptr,
	    const int *len)
{
	int ret;
	struct ip6t_get_entries get;
	struct xt_table *t;

	if (*len < sizeof(get))
		return -EINVAL;
	if (copy_from_user(&get, uptr, sizeof(get)) != 0)
		return -EFAULT;
	if (*len != sizeof(struct ip6t_get_entries) + get.size)
		return -EINVAL;

	get.name[sizeof(get.name) - 1] = '\0';

	t = xt_find_table_lock(net, AF_INET6, get.name);
	if (!IS_ERR(t)) {
		struct xt_table_info *private = t->private;
		if (get.size == private->size)
			ret = copy_entries_to_user(private->size,
						   t, uptr->entrytable);
		else
			ret = -EAGAIN;

		module_put(t->me);
		xt_table_unlock(t);
	} else
		ret = PTR_ERR(t);

	return ret;
}

Project: linux

static int get_info(struct net *net, void __user *user,
		    const int *len, int compat)
{
	char name[XT_TABLE_MAXNAMELEN];
	struct xt_table *t;
	int ret;

	if (*len != sizeof(struct ip6t_getinfo))
		return -EINVAL;

	if (copy_from_user(name, user, sizeof(name)) != 0)
		return -EFAULT;

	name[XT_TABLE_MAXNAMELEN-1] = '\0';
#ifdef CONFIG_COMPAT
	if (compat)
		xt_compat_lock(AF_INET6);
#endif
	t = xt_request_find_table_lock(net, AF_INET6, name);
	if (!IS_ERR(t)) {
		struct ip6t_getinfo info;
		const struct xt_table_info *private = t->private;
#ifdef CONFIG_COMPAT
		struct xt_table_info tmp;

		if (compat) {
			ret = compat_table_info(private, &tmp);
			xt_compat_flush_offsets(AF_INET6);
			private = &tmp;
		}
#endif
		memset(&info, 0, sizeof(info));
		info.valid_hooks = t->valid_hooks;
		memcpy(info.hook_entry, private->hook_entry,
		       sizeof(info.hook_entry));
		memcpy(info.underflow, private->underflow,
		       sizeof(info.underflow));
		info.num_entries = private->number;
		info.size = private->size;
		strcpy(info.name, name);

		if (copy_to_user(user, &info, *len) != 0)
			ret = -EFAULT;
		else
			ret = 0;

		xt_table_unlock(t);
		module_put(t->me);
	} else
		ret = PTR_ERR(t);
#ifdef CONFIG_COMPAT
	if (compat)
		xt_compat_unlock(AF_INET6);
#endif
	return ret;
}

Project: linux

static void get_old_counters(const struct xt_table_info *t,
			     struct xt_counters counters[])
{
	struct ip6t_entry *iter;
	unsigned int cpu, i;

	for_each_possible_cpu(cpu) {
		i = 0;
		xt_entry_foreach(iter, t->entries, t->size) {
			const struct xt_counters *tmp;

			tmp = xt_get_per_cpu_counter(&iter->counters, cpu);
			ADD_COUNTER(counters[i], tmp->bcnt, tmp->pcnt);
			++i;
		}
		cond_resched();
	}
}

Project: linux

icmp6_match(const struct sk_buff *skb, struct xt_action_param *par)
{
	const struct icmp6hdr *ic;
	struct icmp6hdr _icmph;
	const struct ip6t_icmp *icmpinfo = par->matchinfo;

	/* Must not be a fragment. */
	if (par->fragoff != 0)
		return false;

	ic = skb_header_pointer(skb, par->thoff, sizeof(_icmph), &_icmph);
	if (ic == NULL) {
		/* We've been asked to examine this packet, and we
		 * can't.  Hence, no choice but to drop.
		 */
		par->hotdrop = true;
		return false;
	}

	return icmp6_type_code_match(icmpinfo->type,
				     icmpinfo->code[0],
				     icmpinfo->code[1],
				     ic->icmp6_type, ic->icmp6_code,
				     !!(icmpinfo->invflags&IP6T_ICMP_INV));
}

Project: linux

ip6_checkentry(const struct ip6t_ip6 *ipv6)
{
	if (ipv6->flags & ~IP6T_F_MASK)
		return false;
	if (ipv6->invflags & ~IP6T_INV_MASK)
		return false;

	return true;
}

Project: linux

static int __init ip6_tables_init(void)
{
	int ret;

	ret = register_pernet_subsys(&ip6_tables_net_ops);
	if (ret < 0)
		goto err1;

	/* No one else will be downing sem now, so we won't sleep */
	ret = xt_register_targets(ip6t_builtin_tg, ARRAY_SIZE(ip6t_builtin_tg));
	if (ret < 0)
		goto err2;
	ret = xt_register_matches(ip6t_builtin_mt, ARRAY_SIZE(ip6t_builtin_mt));
	if (ret < 0)
		goto err4;

	/* Register setsockopt */
	ret = nf_register_sockopt(&ip6t_sockopts);
	if (ret < 0)
		goto err5;

	return 0;

err5:
	xt_unregister_matches(ip6t_builtin_mt, ARRAY_SIZE(ip6t_builtin_mt));
err4:
	xt_unregister_targets(ip6t_builtin_tg, ARRAY_SIZE(ip6t_builtin_tg));
err2:
	unregister_pernet_subsys(&ip6_tables_net_ops);
err1:
	return ret;
}

Project: linux

translate_compat_table(struct net *net,
		       struct xt_table_info **pinfo,
		       void **pentry0,
		       const struct compat_ip6t_replace *compatr)
{
	unsigned int i, j;
	struct xt_table_info *newinfo, *info;
	void *pos, *entry0, *entry1;
	struct compat_ip6t_entry *iter0;
	struct ip6t_replace repl;
	unsigned int size;
	int ret = 0;

	info = *pinfo;
	entry0 = *pentry0;
	size = compatr->size;
	info->number = compatr->num_entries;

	j = 0;
	xt_compat_lock(AF_INET6);
	xt_compat_init_offsets(AF_INET6, compatr->num_entries);
	/* Walk through entries, checking offsets. */
	xt_entry_foreach(iter0, entry0, compatr->size) {
		ret = check_compat_entry_size_and_hooks(iter0, info, &size,
							entry0,
							entry0 + compatr->size);
		if (ret != 0)
			goto out_unlock;
		++j;
	}

	ret = -EINVAL;
	if (j != compatr->num_entries)
		goto out_unlock;

	ret = -ENOMEM;
	newinfo = xt_alloc_table_info(size);
	if (!newinfo)
		goto out_unlock;

	newinfo->number = compatr->num_entries;
	for (i = 0; i < NF_INET_NUMHOOKS; i++) {
		newinfo->hook_entry[i] = compatr->hook_entry[i];
		newinfo->underflow[i] = compatr->underflow[i];
	}
	entry1 = newinfo->entries;
	pos = entry1;
	size = compatr->size;
	xt_entry_foreach(iter0, entry0, compatr->size)
		compat_copy_entry_from_user(iter0, &pos, &size,
					    newinfo, entry1);

	/* all module references in entry0 are now gone. */
	xt_compat_flush_offsets(AF_INET6);
	xt_compat_unlock(AF_INET6);

	memcpy(&repl, compatr, sizeof(*compatr));

	for (i = 0; i < NF_INET_NUMHOOKS; i++) {
		repl.hook_entry[i] = newinfo->hook_entry[i];
		repl.underflow[i] = newinfo->underflow[i];
	}

	repl.num_counters = 0;
	repl.counters = NULL;
	repl.size = newinfo->size;
	ret = translate_table(net, newinfo, entry1, &repl);
	if (ret)
		goto free_newinfo;

	*pinfo = newinfo;
	*pentry0 = entry1;
	xt_free_table_info(info);
	return 0;

free_newinfo:
	xt_free_table_info(newinfo);
	return ret;
out_unlock:
	xt_compat_flush_offsets(AF_INET6);
	xt_compat_unlock(AF_INET6);
	xt_entry_foreach(iter0, entry0, compatr->size) {
		if (j-- == 0)
			break;
		compat_release_entry(iter0);
	}
	return ret;
}