Revision e7b526bb852cdd67b24e174da6850222f8da41b1 authored by Chris Wilson on 02 June 2010, 07:30:48 UTC, committed by Linus Torvalds on 06 June 2010, 03:37:37 UTC
Cursors need to be in the GTT domain when being accessed by the GPU. Previously this was a fortuitous byproduct of userspace using pwrite() to upload the image data into the cursor. The redundant clflush was removed in commit 9b8c4a and so the image was no longer being flushed out of the caches into main memory. One could also devise a scenario where the cursor was rendered by the GPU, prior to being attached as the cursor, resulting in similar corruption due to the missing MI_FLUSH. Fixes: Bug 28335 - Cursor corruption caused by commit 9b8c4a0b21 https://bugs.freedesktop.org/show_bug.cgi?id=28335 Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Reported-and-tested-by: Jeff Chua <jeff.chua.linux@gmail.com> Tested-by: Linus Torvalds <torvalds@linux-foundation.org> Reported-by: Andy Isaacson <adi@hexapodia.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
1 parent 78b3655
x_tables.c
/*
* x_tables core - Backend for {ip,ip6,arp}_tables
*
* Copyright (C) 2006-2006 Harald Welte <laforge@netfilter.org>
*
* Based on existing ip_tables code which is
* Copyright (C) 1999 Paul `Rusty' Russell & Michael J. Neuling
* Copyright (C) 2000-2005 Netfilter Core Team <coreteam@netfilter.org>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/kernel.h>
#include <linux/socket.h>
#include <linux/net.h>
#include <linux/proc_fs.h>
#include <linux/seq_file.h>
#include <linux/string.h>
#include <linux/vmalloc.h>
#include <linux/mutex.h>
#include <linux/mm.h>
#include <linux/slab.h>
#include <net/net_namespace.h>
#include <linux/netfilter/x_tables.h>
#include <linux/netfilter_arp.h>
#include <linux/netfilter_ipv4/ip_tables.h>
#include <linux/netfilter_ipv6/ip6_tables.h>
#include <linux/netfilter_arp/arp_tables.h>
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Harald Welte <laforge@netfilter.org>");
MODULE_DESCRIPTION("{ip,ip6,arp,eb}_tables backend module");
#define SMP_ALIGN(x) (((x) + SMP_CACHE_BYTES-1) & ~(SMP_CACHE_BYTES-1))
struct compat_delta {
struct compat_delta *next;
unsigned int offset;
int delta;
};
struct xt_af {
struct mutex mutex;
struct list_head match;
struct list_head target;
#ifdef CONFIG_COMPAT
struct mutex compat_mutex;
struct compat_delta *compat_offsets;
#endif
};
static struct xt_af *xt;
static const char *const xt_prefix[NFPROTO_NUMPROTO] = {
[NFPROTO_UNSPEC] = "x",
[NFPROTO_IPV4] = "ip",
[NFPROTO_ARP] = "arp",
[NFPROTO_BRIDGE] = "eb",
[NFPROTO_IPV6] = "ip6",
};
/* Allow this many total (re)entries. */
static const unsigned int xt_jumpstack_multiplier = 2;
/* Registration hooks for targets. */
int
xt_register_target(struct xt_target *target)
{
u_int8_t af = target->family;
int ret;
ret = mutex_lock_interruptible(&xt[af].mutex);
if (ret != 0)
return ret;
list_add(&target->list, &xt[af].target);
mutex_unlock(&xt[af].mutex);
return ret;
}
EXPORT_SYMBOL(xt_register_target);
void
xt_unregister_target(struct xt_target *target)
{
u_int8_t af = target->family;
mutex_lock(&xt[af].mutex);
list_del(&target->list);
mutex_unlock(&xt[af].mutex);
}
EXPORT_SYMBOL(xt_unregister_target);
int
xt_register_targets(struct xt_target *target, unsigned int n)
{
unsigned int i;
int err = 0;
for (i = 0; i < n; i++) {
err = xt_register_target(&target[i]);
if (err)
goto err;
}
return err;
err:
if (i > 0)
xt_unregister_targets(target, i);
return err;
}
EXPORT_SYMBOL(xt_register_targets);
void
xt_unregister_targets(struct xt_target *target, unsigned int n)
{
unsigned int i;
for (i = 0; i < n; i++)
xt_unregister_target(&target[i]);
}
EXPORT_SYMBOL(xt_unregister_targets);
int
xt_register_match(struct xt_match *match)
{
u_int8_t af = match->family;
int ret;
ret = mutex_lock_interruptible(&xt[af].mutex);
if (ret != 0)
return ret;
list_add(&match->list, &xt[af].match);
mutex_unlock(&xt[af].mutex);
return ret;
}
EXPORT_SYMBOL(xt_register_match);
void
xt_unregister_match(struct xt_match *match)
{
u_int8_t af = match->family;
mutex_lock(&xt[af].mutex);
list_del(&match->list);
mutex_unlock(&xt[af].mutex);
}
EXPORT_SYMBOL(xt_unregister_match);
int
xt_register_matches(struct xt_match *match, unsigned int n)
{
unsigned int i;
int err = 0;
for (i = 0; i < n; i++) {
err = xt_register_match(&match[i]);
if (err)
goto err;
}
return err;
err:
if (i > 0)
xt_unregister_matches(match, i);
return err;
}
EXPORT_SYMBOL(xt_register_matches);
void
xt_unregister_matches(struct xt_match *match, unsigned int n)
{
unsigned int i;
for (i = 0; i < n; i++)
xt_unregister_match(&match[i]);
}
EXPORT_SYMBOL(xt_unregister_matches);
/*
* These are weird, but module loading must not be done with mutex
* held (since they will register), and we have to have a single
* function to use try_then_request_module().
*/
/* Find match, grabs ref. Returns ERR_PTR() on error. */
struct xt_match *xt_find_match(u8 af, const char *name, u8 revision)
{
struct xt_match *m;
int err = 0;
if (mutex_lock_interruptible(&xt[af].mutex) != 0)
return ERR_PTR(-EINTR);
list_for_each_entry(m, &xt[af].match, list) {
if (strcmp(m->name, name) == 0) {
if (m->revision == revision) {
if (try_module_get(m->me)) {
mutex_unlock(&xt[af].mutex);
return m;
}
} else
err = -EPROTOTYPE; /* Found something. */
}
}
mutex_unlock(&xt[af].mutex);
if (af != NFPROTO_UNSPEC)
/* Try searching again in the family-independent list */
return xt_find_match(NFPROTO_UNSPEC, name, revision);
return ERR_PTR(err);
}
EXPORT_SYMBOL(xt_find_match);
struct xt_match *
xt_request_find_match(uint8_t nfproto, const char *name, uint8_t revision)
{
struct xt_match *match;
match = try_then_request_module(xt_find_match(nfproto, name, revision),
"%st_%s", xt_prefix[nfproto], name);
return (match != NULL) ? match : ERR_PTR(-ENOENT);
}
EXPORT_SYMBOL_GPL(xt_request_find_match);
/* Find target, grabs ref. Returns ERR_PTR() on error. */
struct xt_target *xt_find_target(u8 af, const char *name, u8 revision)
{
struct xt_target *t;
int err = 0;
if (mutex_lock_interruptible(&xt[af].mutex) != 0)
return ERR_PTR(-EINTR);
list_for_each_entry(t, &xt[af].target, list) {
if (strcmp(t->name, name) == 0) {
if (t->revision == revision) {
if (try_module_get(t->me)) {
mutex_unlock(&xt[af].mutex);
return t;
}
} else
err = -EPROTOTYPE; /* Found something. */
}
}
mutex_unlock(&xt[af].mutex);
if (af != NFPROTO_UNSPEC)
/* Try searching again in the family-independent list */
return xt_find_target(NFPROTO_UNSPEC, name, revision);
return ERR_PTR(err);
}
EXPORT_SYMBOL(xt_find_target);
struct xt_target *xt_request_find_target(u8 af, const char *name, u8 revision)
{
struct xt_target *target;
target = try_then_request_module(xt_find_target(af, name, revision),
"%st_%s", xt_prefix[af], name);
return (target != NULL) ? target : ERR_PTR(-ENOENT);
}
EXPORT_SYMBOL_GPL(xt_request_find_target);
static int match_revfn(u8 af, const char *name, u8 revision, int *bestp)
{
const struct xt_match *m;
int have_rev = 0;
list_for_each_entry(m, &xt[af].match, list) {
if (strcmp(m->name, name) == 0) {
if (m->revision > *bestp)
*bestp = m->revision;
if (m->revision == revision)
have_rev = 1;
}
}
if (af != NFPROTO_UNSPEC && !have_rev)
return match_revfn(NFPROTO_UNSPEC, name, revision, bestp);
return have_rev;
}
static int target_revfn(u8 af, const char *name, u8 revision, int *bestp)
{
const struct xt_target *t;
int have_rev = 0;
list_for_each_entry(t, &xt[af].target, list) {
if (strcmp(t->name, name) == 0) {
if (t->revision > *bestp)
*bestp = t->revision;
if (t->revision == revision)
have_rev = 1;
}
}
if (af != NFPROTO_UNSPEC && !have_rev)
return target_revfn(NFPROTO_UNSPEC, name, revision, bestp);
return have_rev;
}
/* Returns true or false (if no such extension at all) */
int xt_find_revision(u8 af, const char *name, u8 revision, int target,
int *err)
{
int have_rev, best = -1;
if (mutex_lock_interruptible(&xt[af].mutex) != 0) {
*err = -EINTR;
return 1;
}
if (target == 1)
have_rev = target_revfn(af, name, revision, &best);
else
have_rev = match_revfn(af, name, revision, &best);
mutex_unlock(&xt[af].mutex);
/* Nothing at all? Return 0 to try loading module. */
if (best == -1) {
*err = -ENOENT;
return 0;
}
*err = best;
if (!have_rev)
*err = -EPROTONOSUPPORT;
return 1;
}
EXPORT_SYMBOL_GPL(xt_find_revision);
static char *textify_hooks(char *buf, size_t size, unsigned int mask)
{
static const char *const names[] = {
"PREROUTING", "INPUT", "FORWARD",
"OUTPUT", "POSTROUTING", "BROUTING",
};
unsigned int i;
char *p = buf;
bool np = false;
int res;
*p = '\0';
for (i = 0; i < ARRAY_SIZE(names); ++i) {
if (!(mask & (1 << i)))
continue;
res = snprintf(p, size, "%s%s", np ? "/" : "", names[i]);
if (res > 0) {
size -= res;
p += res;
}
np = true;
}
return buf;
}
int xt_check_match(struct xt_mtchk_param *par,
unsigned int size, u_int8_t proto, bool inv_proto)
{
int ret;
if (XT_ALIGN(par->match->matchsize) != size &&
par->match->matchsize != -1) {
/*
* ebt_among is exempt from centralized matchsize checking
* because it uses a dynamic-size data set.
*/
pr_err("%s_tables: %s.%u match: invalid size "
"%u (kernel) != (user) %u\n",
xt_prefix[par->family], par->match->name,
par->match->revision,
XT_ALIGN(par->match->matchsize), size);
return -EINVAL;
}
if (par->match->table != NULL &&
strcmp(par->match->table, par->table) != 0) {
pr_err("%s_tables: %s match: only valid in %s table, not %s\n",
xt_prefix[par->family], par->match->name,
par->match->table, par->table);
return -EINVAL;
}
if (par->match->hooks && (par->hook_mask & ~par->match->hooks) != 0) {
char used[64], allow[64];
pr_err("%s_tables: %s match: used from hooks %s, but only "
"valid from %s\n",
xt_prefix[par->family], par->match->name,
textify_hooks(used, sizeof(used), par->hook_mask),
textify_hooks(allow, sizeof(allow), par->match->hooks));
return -EINVAL;
}
if (par->match->proto && (par->match->proto != proto || inv_proto)) {
pr_err("%s_tables: %s match: only valid for protocol %u\n",
xt_prefix[par->family], par->match->name,
par->match->proto);
return -EINVAL;
}
if (par->match->checkentry != NULL) {
ret = par->match->checkentry(par);
if (ret < 0)
return ret;
else if (ret > 0)
/* Flag up potential errors. */
return -EIO;
}
return 0;
}
EXPORT_SYMBOL_GPL(xt_check_match);
#ifdef CONFIG_COMPAT
int xt_compat_add_offset(u_int8_t af, unsigned int offset, short delta)
{
struct compat_delta *tmp;
tmp = kmalloc(sizeof(struct compat_delta), GFP_KERNEL);
if (!tmp)
return -ENOMEM;
tmp->offset = offset;
tmp->delta = delta;
if (xt[af].compat_offsets) {
tmp->next = xt[af].compat_offsets->next;
xt[af].compat_offsets->next = tmp;
} else {
xt[af].compat_offsets = tmp;
tmp->next = NULL;
}
return 0;
}
EXPORT_SYMBOL_GPL(xt_compat_add_offset);
void xt_compat_flush_offsets(u_int8_t af)
{
struct compat_delta *tmp, *next;
if (xt[af].compat_offsets) {
for (tmp = xt[af].compat_offsets; tmp; tmp = next) {
next = tmp->next;
kfree(tmp);
}
xt[af].compat_offsets = NULL;
}
}
EXPORT_SYMBOL_GPL(xt_compat_flush_offsets);
int xt_compat_calc_jump(u_int8_t af, unsigned int offset)
{
struct compat_delta *tmp;
int delta;
for (tmp = xt[af].compat_offsets, delta = 0; tmp; tmp = tmp->next)
if (tmp->offset < offset)
delta += tmp->delta;
return delta;
}
EXPORT_SYMBOL_GPL(xt_compat_calc_jump);
int xt_compat_match_offset(const struct xt_match *match)
{
u_int16_t csize = match->compatsize ? : match->matchsize;
return XT_ALIGN(match->matchsize) - COMPAT_XT_ALIGN(csize);
}
EXPORT_SYMBOL_GPL(xt_compat_match_offset);
int xt_compat_match_from_user(struct xt_entry_match *m, void **dstptr,
unsigned int *size)
{
const struct xt_match *match = m->u.kernel.match;
struct compat_xt_entry_match *cm = (struct compat_xt_entry_match *)m;
int pad, off = xt_compat_match_offset(match);
u_int16_t msize = cm->u.user.match_size;
m = *dstptr;
memcpy(m, cm, sizeof(*cm));
if (match->compat_from_user)
match->compat_from_user(m->data, cm->data);
else
memcpy(m->data, cm->data, msize - sizeof(*cm));
pad = XT_ALIGN(match->matchsize) - match->matchsize;
if (pad > 0)
memset(m->data + match->matchsize, 0, pad);
msize += off;
m->u.user.match_size = msize;
*size += off;
*dstptr += msize;
return 0;
}
EXPORT_SYMBOL_GPL(xt_compat_match_from_user);
int xt_compat_match_to_user(const struct xt_entry_match *m,
void __user **dstptr, unsigned int *size)
{
const struct xt_match *match = m->u.kernel.match;
struct compat_xt_entry_match __user *cm = *dstptr;
int off = xt_compat_match_offset(match);
u_int16_t msize = m->u.user.match_size - off;
if (copy_to_user(cm, m, sizeof(*cm)) ||
put_user(msize, &cm->u.user.match_size) ||
copy_to_user(cm->u.user.name, m->u.kernel.match->name,
strlen(m->u.kernel.match->name) + 1))
return -EFAULT;
if (match->compat_to_user) {
if (match->compat_to_user((void __user *)cm->data, m->data))
return -EFAULT;
} else {
if (copy_to_user(cm->data, m->data, msize - sizeof(*cm)))
return -EFAULT;
}
*size -= off;
*dstptr += msize;
return 0;
}
EXPORT_SYMBOL_GPL(xt_compat_match_to_user);
#endif /* CONFIG_COMPAT */
int xt_check_target(struct xt_tgchk_param *par,
unsigned int size, u_int8_t proto, bool inv_proto)
{
int ret;
if (XT_ALIGN(par->target->targetsize) != size) {
pr_err("%s_tables: %s.%u target: invalid size "
"%u (kernel) != (user) %u\n",
xt_prefix[par->family], par->target->name,
par->target->revision,
XT_ALIGN(par->target->targetsize), size);
return -EINVAL;
}
if (par->target->table != NULL &&
strcmp(par->target->table, par->table) != 0) {
pr_err("%s_tables: %s target: only valid in %s table, not %s\n",
xt_prefix[par->family], par->target->name,
par->target->table, par->table);
return -EINVAL;
}
if (par->target->hooks && (par->hook_mask & ~par->target->hooks) != 0) {
char used[64], allow[64];
pr_err("%s_tables: %s target: used from hooks %s, but only "
"usable from %s\n",
xt_prefix[par->family], par->target->name,
textify_hooks(used, sizeof(used), par->hook_mask),
textify_hooks(allow, sizeof(allow), par->target->hooks));
return -EINVAL;
}
if (par->target->proto && (par->target->proto != proto || inv_proto)) {
pr_err("%s_tables: %s target: only valid for protocol %u\n",
xt_prefix[par->family], par->target->name,
par->target->proto);
return -EINVAL;
}
if (par->target->checkentry != NULL) {
ret = par->target->checkentry(par);
if (ret < 0)
return ret;
else if (ret > 0)
/* Flag up potential errors. */
return -EIO;
}
return 0;
}
EXPORT_SYMBOL_GPL(xt_check_target);
#ifdef CONFIG_COMPAT
int xt_compat_target_offset(const struct xt_target *target)
{
u_int16_t csize = target->compatsize ? : target->targetsize;
return XT_ALIGN(target->targetsize) - COMPAT_XT_ALIGN(csize);
}
EXPORT_SYMBOL_GPL(xt_compat_target_offset);
void xt_compat_target_from_user(struct xt_entry_target *t, void **dstptr,
unsigned int *size)
{
const struct xt_target *target = t->u.kernel.target;
struct compat_xt_entry_target *ct = (struct compat_xt_entry_target *)t;
int pad, off = xt_compat_target_offset(target);
u_int16_t tsize = ct->u.user.target_size;
t = *dstptr;
memcpy(t, ct, sizeof(*ct));
if (target->compat_from_user)
target->compat_from_user(t->data, ct->data);
else
memcpy(t->data, ct->data, tsize - sizeof(*ct));
pad = XT_ALIGN(target->targetsize) - target->targetsize;
if (pad > 0)
memset(t->data + target->targetsize, 0, pad);
tsize += off;
t->u.user.target_size = tsize;
*size += off;
*dstptr += tsize;
}
EXPORT_SYMBOL_GPL(xt_compat_target_from_user);
int xt_compat_target_to_user(const struct xt_entry_target *t,
void __user **dstptr, unsigned int *size)
{
const struct xt_target *target = t->u.kernel.target;
struct compat_xt_entry_target __user *ct = *dstptr;
int off = xt_compat_target_offset(target);
u_int16_t tsize = t->u.user.target_size - off;
if (copy_to_user(ct, t, sizeof(*ct)) ||
put_user(tsize, &ct->u.user.target_size) ||
copy_to_user(ct->u.user.name, t->u.kernel.target->name,
strlen(t->u.kernel.target->name) + 1))
return -EFAULT;
if (target->compat_to_user) {
if (target->compat_to_user((void __user *)ct->data, t->data))
return -EFAULT;
} else {
if (copy_to_user(ct->data, t->data, tsize - sizeof(*ct)))
return -EFAULT;
}
*size -= off;
*dstptr += tsize;
return 0;
}
EXPORT_SYMBOL_GPL(xt_compat_target_to_user);
#endif
struct xt_table_info *xt_alloc_table_info(unsigned int size)
{
struct xt_table_info *newinfo;
int cpu;
/* Pedantry: prevent them from hitting BUG() in vmalloc.c --RR */
if ((SMP_ALIGN(size) >> PAGE_SHIFT) + 2 > totalram_pages)
return NULL;
newinfo = kzalloc(XT_TABLE_INFO_SZ, GFP_KERNEL);
if (!newinfo)
return NULL;
newinfo->size = size;
for_each_possible_cpu(cpu) {
if (size <= PAGE_SIZE)
newinfo->entries[cpu] = kmalloc_node(size,
GFP_KERNEL,
cpu_to_node(cpu));
else
newinfo->entries[cpu] = vmalloc_node(size,
cpu_to_node(cpu));
if (newinfo->entries[cpu] == NULL) {
xt_free_table_info(newinfo);
return NULL;
}
}
return newinfo;
}
EXPORT_SYMBOL(xt_alloc_table_info);
void xt_free_table_info(struct xt_table_info *info)
{
int cpu;
for_each_possible_cpu(cpu) {
if (info->size <= PAGE_SIZE)
kfree(info->entries[cpu]);
else
vfree(info->entries[cpu]);
}
if (info->jumpstack != NULL) {
if (sizeof(void *) * info->stacksize > PAGE_SIZE) {
for_each_possible_cpu(cpu)
vfree(info->jumpstack[cpu]);
} else {
for_each_possible_cpu(cpu)
kfree(info->jumpstack[cpu]);
}
}
if (sizeof(void **) * nr_cpu_ids > PAGE_SIZE)
vfree(info->jumpstack);
else
kfree(info->jumpstack);
free_percpu(info->stackptr);
kfree(info);
}
EXPORT_SYMBOL(xt_free_table_info);
/* Find table by name, grabs mutex & ref. Returns ERR_PTR() on error. */
struct xt_table *xt_find_table_lock(struct net *net, u_int8_t af,
const char *name)
{
struct xt_table *t;
if (mutex_lock_interruptible(&xt[af].mutex) != 0)
return ERR_PTR(-EINTR);
list_for_each_entry(t, &net->xt.tables[af], list)
if (strcmp(t->name, name) == 0 && try_module_get(t->me))
return t;
mutex_unlock(&xt[af].mutex);
return NULL;
}
EXPORT_SYMBOL_GPL(xt_find_table_lock);
void xt_table_unlock(struct xt_table *table)
{
mutex_unlock(&xt[table->af].mutex);
}
EXPORT_SYMBOL_GPL(xt_table_unlock);
#ifdef CONFIG_COMPAT
void xt_compat_lock(u_int8_t af)
{
mutex_lock(&xt[af].compat_mutex);
}
EXPORT_SYMBOL_GPL(xt_compat_lock);
void xt_compat_unlock(u_int8_t af)
{
mutex_unlock(&xt[af].compat_mutex);
}
EXPORT_SYMBOL_GPL(xt_compat_unlock);
#endif
DEFINE_PER_CPU(struct xt_info_lock, xt_info_locks);
EXPORT_PER_CPU_SYMBOL_GPL(xt_info_locks);
static int xt_jumpstack_alloc(struct xt_table_info *i)
{
unsigned int size;
int cpu;
i->stackptr = alloc_percpu(unsigned int);
if (i->stackptr == NULL)
return -ENOMEM;
size = sizeof(void **) * nr_cpu_ids;
if (size > PAGE_SIZE)
i->jumpstack = vmalloc(size);
else
i->jumpstack = kmalloc(size, GFP_KERNEL);
if (i->jumpstack == NULL)
return -ENOMEM;
memset(i->jumpstack, 0, size);
i->stacksize *= xt_jumpstack_multiplier;
size = sizeof(void *) * i->stacksize;
for_each_possible_cpu(cpu) {
if (size > PAGE_SIZE)
i->jumpstack[cpu] = vmalloc_node(size,
cpu_to_node(cpu));
else
i->jumpstack[cpu] = kmalloc_node(size,
GFP_KERNEL, cpu_to_node(cpu));
if (i->jumpstack[cpu] == NULL)
/*
* Freeing will be done later on by the callers. The
* chain is: xt_replace_table -> __do_replace ->
* do_replace -> xt_free_table_info.
*/
return -ENOMEM;
}
return 0;
}
struct xt_table_info *
xt_replace_table(struct xt_table *table,
unsigned int num_counters,
struct xt_table_info *newinfo,
int *error)
{
struct xt_table_info *private;
int ret;
ret = xt_jumpstack_alloc(newinfo);
if (ret < 0) {
*error = ret;
return NULL;
}
/* Do the substitution. */
local_bh_disable();
private = table->private;
/* Check inside lock: is the old number correct? */
if (num_counters != private->number) {
pr_debug("num_counters != table->private->number (%u/%u)\n",
num_counters, private->number);
local_bh_enable();
*error = -EAGAIN;
return NULL;
}
table->private = newinfo;
newinfo->initial_entries = private->initial_entries;
/*
* Even though table entries have now been swapped, other CPU's
* may still be using the old entries. This is okay, because
* resynchronization happens because of the locking done
* during the get_counters() routine.
*/
local_bh_enable();
return private;
}
EXPORT_SYMBOL_GPL(xt_replace_table);
struct xt_table *xt_register_table(struct net *net,
const struct xt_table *input_table,
struct xt_table_info *bootstrap,
struct xt_table_info *newinfo)
{
int ret;
struct xt_table_info *private;
struct xt_table *t, *table;
/* Don't add one object to multiple lists. */
table = kmemdup(input_table, sizeof(struct xt_table), GFP_KERNEL);
if (!table) {
ret = -ENOMEM;
goto out;
}
ret = mutex_lock_interruptible(&xt[table->af].mutex);
if (ret != 0)
goto out_free;
/* Don't autoload: we'd eat our tail... */
list_for_each_entry(t, &net->xt.tables[table->af], list) {
if (strcmp(t->name, table->name) == 0) {
ret = -EEXIST;
goto unlock;
}
}
/* Simplifies replace_table code. */
table->private = bootstrap;
if (!xt_replace_table(table, 0, newinfo, &ret))
goto unlock;
private = table->private;
pr_debug("table->private->number = %u\n", private->number);
/* save number of initial entries */
private->initial_entries = private->number;
list_add(&table->list, &net->xt.tables[table->af]);
mutex_unlock(&xt[table->af].mutex);
return table;
unlock:
mutex_unlock(&xt[table->af].mutex);
out_free:
kfree(table);
out:
return ERR_PTR(ret);
}
EXPORT_SYMBOL_GPL(xt_register_table);
void *xt_unregister_table(struct xt_table *table)
{
struct xt_table_info *private;
mutex_lock(&xt[table->af].mutex);
private = table->private;
list_del(&table->list);
mutex_unlock(&xt[table->af].mutex);
kfree(table);
return private;
}
EXPORT_SYMBOL_GPL(xt_unregister_table);
#ifdef CONFIG_PROC_FS
struct xt_names_priv {
struct seq_net_private p;
u_int8_t af;
};
static void *xt_table_seq_start(struct seq_file *seq, loff_t *pos)
{
struct xt_names_priv *priv = seq->private;
struct net *net = seq_file_net(seq);
u_int8_t af = priv->af;
mutex_lock(&xt[af].mutex);
return seq_list_start(&net->xt.tables[af], *pos);
}
static void *xt_table_seq_next(struct seq_file *seq, void *v, loff_t *pos)
{
struct xt_names_priv *priv = seq->private;
struct net *net = seq_file_net(seq);
u_int8_t af = priv->af;
return seq_list_next(v, &net->xt.tables[af], pos);
}
static void xt_table_seq_stop(struct seq_file *seq, void *v)
{
struct xt_names_priv *priv = seq->private;
u_int8_t af = priv->af;
mutex_unlock(&xt[af].mutex);
}
static int xt_table_seq_show(struct seq_file *seq, void *v)
{
struct xt_table *table = list_entry(v, struct xt_table, list);
if (strlen(table->name))
return seq_printf(seq, "%s\n", table->name);
else
return 0;
}
static const struct seq_operations xt_table_seq_ops = {
.start = xt_table_seq_start,
.next = xt_table_seq_next,
.stop = xt_table_seq_stop,
.show = xt_table_seq_show,
};
static int xt_table_open(struct inode *inode, struct file *file)
{
int ret;
struct xt_names_priv *priv;
ret = seq_open_net(inode, file, &xt_table_seq_ops,
sizeof(struct xt_names_priv));
if (!ret) {
priv = ((struct seq_file *)file->private_data)->private;
priv->af = (unsigned long)PDE(inode)->data;
}
return ret;
}
static const struct file_operations xt_table_ops = {
.owner = THIS_MODULE,
.open = xt_table_open,
.read = seq_read,
.llseek = seq_lseek,
.release = seq_release_net,
};
/*
* Traverse state for ip{,6}_{tables,matches} for helping crossing
* the multi-AF mutexes.
*/
struct nf_mttg_trav {
struct list_head *head, *curr;
uint8_t class, nfproto;
};
enum {
MTTG_TRAV_INIT,
MTTG_TRAV_NFP_UNSPEC,
MTTG_TRAV_NFP_SPEC,
MTTG_TRAV_DONE,
};
static void *xt_mttg_seq_next(struct seq_file *seq, void *v, loff_t *ppos,
bool is_target)
{
static const uint8_t next_class[] = {
[MTTG_TRAV_NFP_UNSPEC] = MTTG_TRAV_NFP_SPEC,
[MTTG_TRAV_NFP_SPEC] = MTTG_TRAV_DONE,
};
struct nf_mttg_trav *trav = seq->private;
switch (trav->class) {
case MTTG_TRAV_INIT:
trav->class = MTTG_TRAV_NFP_UNSPEC;
mutex_lock(&xt[NFPROTO_UNSPEC].mutex);
trav->head = trav->curr = is_target ?
&xt[NFPROTO_UNSPEC].target : &xt[NFPROTO_UNSPEC].match;
break;
case MTTG_TRAV_NFP_UNSPEC:
trav->curr = trav->curr->next;
if (trav->curr != trav->head)
break;
mutex_unlock(&xt[NFPROTO_UNSPEC].mutex);
mutex_lock(&xt[trav->nfproto].mutex);
trav->head = trav->curr = is_target ?
&xt[trav->nfproto].target : &xt[trav->nfproto].match;
trav->class = next_class[trav->class];
break;
case MTTG_TRAV_NFP_SPEC:
trav->curr = trav->curr->next;
if (trav->curr != trav->head)
break;
/* fallthru, _stop will unlock */
default:
return NULL;
}
if (ppos != NULL)
++*ppos;
return trav;
}
static void *xt_mttg_seq_start(struct seq_file *seq, loff_t *pos,
bool is_target)
{
struct nf_mttg_trav *trav = seq->private;
unsigned int j;
trav->class = MTTG_TRAV_INIT;
for (j = 0; j < *pos; ++j)
if (xt_mttg_seq_next(seq, NULL, NULL, is_target) == NULL)
return NULL;
return trav;
}
static void xt_mttg_seq_stop(struct seq_file *seq, void *v)
{
struct nf_mttg_trav *trav = seq->private;
switch (trav->class) {
case MTTG_TRAV_NFP_UNSPEC:
mutex_unlock(&xt[NFPROTO_UNSPEC].mutex);
break;
case MTTG_TRAV_NFP_SPEC:
mutex_unlock(&xt[trav->nfproto].mutex);
break;
}
}
static void *xt_match_seq_start(struct seq_file *seq, loff_t *pos)
{
return xt_mttg_seq_start(seq, pos, false);
}
static void *xt_match_seq_next(struct seq_file *seq, void *v, loff_t *ppos)
{
return xt_mttg_seq_next(seq, v, ppos, false);
}
static int xt_match_seq_show(struct seq_file *seq, void *v)
{
const struct nf_mttg_trav *trav = seq->private;
const struct xt_match *match;
switch (trav->class) {
case MTTG_TRAV_NFP_UNSPEC:
case MTTG_TRAV_NFP_SPEC:
if (trav->curr == trav->head)
return 0;
match = list_entry(trav->curr, struct xt_match, list);
return (*match->name == '\0') ? 0 :
seq_printf(seq, "%s\n", match->name);
}
return 0;
}
static const struct seq_operations xt_match_seq_ops = {
.start = xt_match_seq_start,
.next = xt_match_seq_next,
.stop = xt_mttg_seq_stop,
.show = xt_match_seq_show,
};
static int xt_match_open(struct inode *inode, struct file *file)
{
struct seq_file *seq;
struct nf_mttg_trav *trav;
int ret;
trav = kmalloc(sizeof(*trav), GFP_KERNEL);
if (trav == NULL)
return -ENOMEM;
ret = seq_open(file, &xt_match_seq_ops);
if (ret < 0) {
kfree(trav);
return ret;
}
seq = file->private_data;
seq->private = trav;
trav->nfproto = (unsigned long)PDE(inode)->data;
return 0;
}
static const struct file_operations xt_match_ops = {
.owner = THIS_MODULE,
.open = xt_match_open,
.read = seq_read,
.llseek = seq_lseek,
.release = seq_release_private,
};
static void *xt_target_seq_start(struct seq_file *seq, loff_t *pos)
{
return xt_mttg_seq_start(seq, pos, true);
}
static void *xt_target_seq_next(struct seq_file *seq, void *v, loff_t *ppos)
{
return xt_mttg_seq_next(seq, v, ppos, true);
}
static int xt_target_seq_show(struct seq_file *seq, void *v)
{
const struct nf_mttg_trav *trav = seq->private;
const struct xt_target *target;
switch (trav->class) {
case MTTG_TRAV_NFP_UNSPEC:
case MTTG_TRAV_NFP_SPEC:
if (trav->curr == trav->head)
return 0;
target = list_entry(trav->curr, struct xt_target, list);
return (*target->name == '\0') ? 0 :
seq_printf(seq, "%s\n", target->name);
}
return 0;
}
static const struct seq_operations xt_target_seq_ops = {
.start = xt_target_seq_start,
.next = xt_target_seq_next,
.stop = xt_mttg_seq_stop,
.show = xt_target_seq_show,
};
static int xt_target_open(struct inode *inode, struct file *file)
{
struct seq_file *seq;
struct nf_mttg_trav *trav;
int ret;
trav = kmalloc(sizeof(*trav), GFP_KERNEL);
if (trav == NULL)
return -ENOMEM;
ret = seq_open(file, &xt_target_seq_ops);
if (ret < 0) {
kfree(trav);
return ret;
}
seq = file->private_data;
seq->private = trav;
trav->nfproto = (unsigned long)PDE(inode)->data;
return 0;
}
static const struct file_operations xt_target_ops = {
.owner = THIS_MODULE,
.open = xt_target_open,
.read = seq_read,
.llseek = seq_lseek,
.release = seq_release_private,
};
#define FORMAT_TABLES "_tables_names"
#define FORMAT_MATCHES "_tables_matches"
#define FORMAT_TARGETS "_tables_targets"
#endif /* CONFIG_PROC_FS */
/**
* xt_hook_link - set up hooks for a new table
* @table: table with metadata needed to set up hooks
* @fn: Hook function
*
* This function will take care of creating and registering the necessary
* Netfilter hooks for XT tables.
*/
struct nf_hook_ops *xt_hook_link(const struct xt_table *table, nf_hookfn *fn)
{
unsigned int hook_mask = table->valid_hooks;
uint8_t i, num_hooks = hweight32(hook_mask);
uint8_t hooknum;
struct nf_hook_ops *ops;
int ret;
ops = kmalloc(sizeof(*ops) * num_hooks, GFP_KERNEL);
if (ops == NULL)
return ERR_PTR(-ENOMEM);
for (i = 0, hooknum = 0; i < num_hooks && hook_mask != 0;
hook_mask >>= 1, ++hooknum) {
if (!(hook_mask & 1))
continue;
ops[i].hook = fn;
ops[i].owner = table->me;
ops[i].pf = table->af;
ops[i].hooknum = hooknum;
ops[i].priority = table->priority;
++i;
}
ret = nf_register_hooks(ops, num_hooks);
if (ret < 0) {
kfree(ops);
return ERR_PTR(ret);
}
return ops;
}
EXPORT_SYMBOL_GPL(xt_hook_link);
/**
* xt_hook_unlink - remove hooks for a table
* @ops: nf_hook_ops array as returned by nf_hook_link
* @hook_mask: the very same mask that was passed to nf_hook_link
*/
void xt_hook_unlink(const struct xt_table *table, struct nf_hook_ops *ops)
{
nf_unregister_hooks(ops, hweight32(table->valid_hooks));
kfree(ops);
}
EXPORT_SYMBOL_GPL(xt_hook_unlink);
int xt_proto_init(struct net *net, u_int8_t af)
{
#ifdef CONFIG_PROC_FS
char buf[XT_FUNCTION_MAXNAMELEN];
struct proc_dir_entry *proc;
#endif
if (af >= ARRAY_SIZE(xt_prefix))
return -EINVAL;
#ifdef CONFIG_PROC_FS
strlcpy(buf, xt_prefix[af], sizeof(buf));
strlcat(buf, FORMAT_TABLES, sizeof(buf));
proc = proc_create_data(buf, 0440, net->proc_net, &xt_table_ops,
(void *)(unsigned long)af);
if (!proc)
goto out;
strlcpy(buf, xt_prefix[af], sizeof(buf));
strlcat(buf, FORMAT_MATCHES, sizeof(buf));
proc = proc_create_data(buf, 0440, net->proc_net, &xt_match_ops,
(void *)(unsigned long)af);
if (!proc)
goto out_remove_tables;
strlcpy(buf, xt_prefix[af], sizeof(buf));
strlcat(buf, FORMAT_TARGETS, sizeof(buf));
proc = proc_create_data(buf, 0440, net->proc_net, &xt_target_ops,
(void *)(unsigned long)af);
if (!proc)
goto out_remove_matches;
#endif
return 0;
#ifdef CONFIG_PROC_FS
out_remove_matches:
strlcpy(buf, xt_prefix[af], sizeof(buf));
strlcat(buf, FORMAT_MATCHES, sizeof(buf));
proc_net_remove(net, buf);
out_remove_tables:
strlcpy(buf, xt_prefix[af], sizeof(buf));
strlcat(buf, FORMAT_TABLES, sizeof(buf));
proc_net_remove(net, buf);
out:
return -1;
#endif
}
EXPORT_SYMBOL_GPL(xt_proto_init);
void xt_proto_fini(struct net *net, u_int8_t af)
{
#ifdef CONFIG_PROC_FS
char buf[XT_FUNCTION_MAXNAMELEN];
strlcpy(buf, xt_prefix[af], sizeof(buf));
strlcat(buf, FORMAT_TABLES, sizeof(buf));
proc_net_remove(net, buf);
strlcpy(buf, xt_prefix[af], sizeof(buf));
strlcat(buf, FORMAT_TARGETS, sizeof(buf));
proc_net_remove(net, buf);
strlcpy(buf, xt_prefix[af], sizeof(buf));
strlcat(buf, FORMAT_MATCHES, sizeof(buf));
proc_net_remove(net, buf);
#endif /*CONFIG_PROC_FS*/
}
EXPORT_SYMBOL_GPL(xt_proto_fini);
static int __net_init xt_net_init(struct net *net)
{
int i;
for (i = 0; i < NFPROTO_NUMPROTO; i++)
INIT_LIST_HEAD(&net->xt.tables[i]);
return 0;
}
static struct pernet_operations xt_net_ops = {
.init = xt_net_init,
};
static int __init xt_init(void)
{
unsigned int i;
int rv;
for_each_possible_cpu(i) {
struct xt_info_lock *lock = &per_cpu(xt_info_locks, i);
spin_lock_init(&lock->lock);
lock->readers = 0;
}
xt = kmalloc(sizeof(struct xt_af) * NFPROTO_NUMPROTO, GFP_KERNEL);
if (!xt)
return -ENOMEM;
for (i = 0; i < NFPROTO_NUMPROTO; i++) {
mutex_init(&xt[i].mutex);
#ifdef CONFIG_COMPAT
mutex_init(&xt[i].compat_mutex);
xt[i].compat_offsets = NULL;
#endif
INIT_LIST_HEAD(&xt[i].target);
INIT_LIST_HEAD(&xt[i].match);
}
rv = register_pernet_subsys(&xt_net_ops);
if (rv < 0)
kfree(xt);
return rv;
}
static void __exit xt_fini(void)
{
unregister_pernet_subsys(&xt_net_ops);
kfree(xt);
}
module_init(xt_init);
module_exit(xt_fini);
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