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linux/net/ieee802154/wpan-class.c
Denis Kirjanov a6c0f8217c ieee802154: Fix possible NULL pointer dereference in wpan_phy_alloc
Check for NULL pointer after kzalloc

Signed-off-by: Denis Kirjanov <dkirjanov@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-05-23 23:11:07 -07:00

227 lines
5.1 KiB
C

/*
* Copyright (C) 2007, 2008, 2009 Siemens AG
*
* 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.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*
*/
#include <linux/slab.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/device.h>
#include <net/wpan-phy.h>
#include "ieee802154.h"
#define MASTER_SHOW_COMPLEX(name, format_string, args...) \
static ssize_t name ## _show(struct device *dev, \
struct device_attribute *attr, char *buf) \
{ \
struct wpan_phy *phy = container_of(dev, struct wpan_phy, dev); \
int ret; \
\
mutex_lock(&phy->pib_lock); \
ret = snprintf(buf, PAGE_SIZE, format_string "\n", args); \
mutex_unlock(&phy->pib_lock); \
return ret; \
}
#define MASTER_SHOW(field, format_string) \
MASTER_SHOW_COMPLEX(field, format_string, phy->field)
MASTER_SHOW(current_channel, "%d");
MASTER_SHOW(current_page, "%d");
MASTER_SHOW_COMPLEX(transmit_power, "%d +- %d dB",
((signed char) (phy->transmit_power << 2)) >> 2,
(phy->transmit_power >> 6) ? (phy->transmit_power >> 6) * 3 : 1 );
MASTER_SHOW(cca_mode, "%d");
static ssize_t channels_supported_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct wpan_phy *phy = container_of(dev, struct wpan_phy, dev);
int ret;
int i, len = 0;
mutex_lock(&phy->pib_lock);
for (i = 0; i < 32; i++) {
ret = snprintf(buf + len, PAGE_SIZE - len,
"%#09x\n", phy->channels_supported[i]);
if (ret < 0)
break;
len += ret;
}
mutex_unlock(&phy->pib_lock);
return len;
}
static struct device_attribute pmib_attrs[] = {
__ATTR_RO(current_channel),
__ATTR_RO(current_page),
__ATTR_RO(channels_supported),
__ATTR_RO(transmit_power),
__ATTR_RO(cca_mode),
{},
};
static void wpan_phy_release(struct device *d)
{
struct wpan_phy *phy = container_of(d, struct wpan_phy, dev);
kfree(phy);
}
static struct class wpan_phy_class = {
.name = "ieee802154",
.dev_release = wpan_phy_release,
.dev_attrs = pmib_attrs,
};
static DEFINE_MUTEX(wpan_phy_mutex);
static int wpan_phy_idx;
static int wpan_phy_match(struct device *dev, void *data)
{
return !strcmp(dev_name(dev), (const char *)data);
}
struct wpan_phy *wpan_phy_find(const char *str)
{
struct device *dev;
if (WARN_ON(!str))
return NULL;
dev = class_find_device(&wpan_phy_class, NULL,
(void *)str, wpan_phy_match);
if (!dev)
return NULL;
return container_of(dev, struct wpan_phy, dev);
}
EXPORT_SYMBOL(wpan_phy_find);
struct wpan_phy_iter_data {
int (*fn)(struct wpan_phy *phy, void *data);
void *data;
};
static int wpan_phy_iter(struct device *dev, void *_data)
{
struct wpan_phy_iter_data *wpid = _data;
struct wpan_phy *phy = container_of(dev, struct wpan_phy, dev);
return wpid->fn(phy, wpid->data);
}
int wpan_phy_for_each(int (*fn)(struct wpan_phy *phy, void *data),
void *data)
{
struct wpan_phy_iter_data wpid = {
.fn = fn,
.data = data,
};
return class_for_each_device(&wpan_phy_class, NULL,
&wpid, wpan_phy_iter);
}
EXPORT_SYMBOL(wpan_phy_for_each);
static int wpan_phy_idx_valid(int idx)
{
return idx >= 0;
}
struct wpan_phy *wpan_phy_alloc(size_t priv_size)
{
struct wpan_phy *phy = kzalloc(sizeof(*phy) + priv_size,
GFP_KERNEL);
if (!phy)
goto out;
mutex_lock(&wpan_phy_mutex);
phy->idx = wpan_phy_idx++;
if (unlikely(!wpan_phy_idx_valid(phy->idx))) {
wpan_phy_idx--;
mutex_unlock(&wpan_phy_mutex);
kfree(phy);
goto out;
}
mutex_unlock(&wpan_phy_mutex);
mutex_init(&phy->pib_lock);
device_initialize(&phy->dev);
dev_set_name(&phy->dev, "wpan-phy%d", phy->idx);
phy->dev.class = &wpan_phy_class;
phy->current_channel = -1; /* not initialised */
phy->current_page = 0; /* for compatibility */
return phy;
out:
return NULL;
}
EXPORT_SYMBOL(wpan_phy_alloc);
int wpan_phy_register(struct wpan_phy *phy)
{
return device_add(&phy->dev);
}
EXPORT_SYMBOL(wpan_phy_register);
void wpan_phy_unregister(struct wpan_phy *phy)
{
device_del(&phy->dev);
}
EXPORT_SYMBOL(wpan_phy_unregister);
void wpan_phy_free(struct wpan_phy *phy)
{
put_device(&phy->dev);
}
EXPORT_SYMBOL(wpan_phy_free);
static int __init wpan_phy_class_init(void)
{
int rc;
rc = class_register(&wpan_phy_class);
if (rc)
goto err;
rc = ieee802154_nl_init();
if (rc)
goto err_nl;
return 0;
err_nl:
class_unregister(&wpan_phy_class);
err:
return rc;
}
subsys_initcall(wpan_phy_class_init);
static void __exit wpan_phy_class_exit(void)
{
ieee802154_nl_exit();
class_unregister(&wpan_phy_class);
}
module_exit(wpan_phy_class_exit);
MODULE_LICENSE("GPL v2");
MODULE_DESCRIPTION("IEEE 802.15.4 configuration interface");
MODULE_AUTHOR("Dmitry Eremin-Solenikov");