tmp_suning_uos_patched/drivers/net/wireless/mac80211_hwsim.c
Ian Schram 3a33cc108d mac80211_hwsim.c: fix: BUG: unable to handle kernel NULL pointer dereference at 0000000000000370
I was looking at this out of interest, but I'm in no way familiar with
the code.

Looks to me that the error handling code in mac80211_hwsim is awkward.
Which leads to it calling ieee80211_unregister_hw even when
ieee80211_register_hw failed.

The function has a for loop where it generates all simulated radios.
when something fails, the error handling will call mac80211_hwsim_free
which frees all simulated radios who's pointer isn't zero. However the
information stored is insufficient to determine whether or not the call
to ieee80211_register_hw succeeded or not for a specific radio. The
included patch makes init_mac80211_hwsim clean up the current simulated
radio, and then calls into mac80211_hwsim_free to clean up all the
radios that did succeed.

This however doesn't explain why the rate control registration failed..
build tested this, but had some problems reproducing the original
problem.

Signed-off-by: Ian Schram <ischram@telenet.be>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-07-21 13:19:35 -07:00

522 lines
13 KiB
C

/*
* mac80211_hwsim - software simulator of 802.11 radio(s) for mac80211
* Copyright (c) 2008, Jouni Malinen <j@w1.fi>
*
* 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.
*/
/*
* TODO:
* - IBSS mode simulation (Beacon transmission with competition for "air time")
* - IEEE 802.11a and 802.11n modes
* - RX filtering based on filter configuration (data->rx_filter)
*/
#include <net/mac80211.h>
#include <net/ieee80211_radiotap.h>
#include <linux/if_arp.h>
#include <linux/rtnetlink.h>
#include <linux/etherdevice.h>
MODULE_AUTHOR("Jouni Malinen");
MODULE_DESCRIPTION("Software simulator of 802.11 radio(s) for mac80211");
MODULE_LICENSE("GPL");
static int radios = 2;
module_param(radios, int, 0444);
MODULE_PARM_DESC(radios, "Number of simulated radios");
static struct class *hwsim_class;
static struct ieee80211_hw **hwsim_radios;
static int hwsim_radio_count;
static struct net_device *hwsim_mon; /* global monitor netdev */
static const struct ieee80211_channel hwsim_channels[] = {
{ .center_freq = 2412 },
{ .center_freq = 2417 },
{ .center_freq = 2422 },
{ .center_freq = 2427 },
{ .center_freq = 2432 },
{ .center_freq = 2437 },
{ .center_freq = 2442 },
{ .center_freq = 2447 },
{ .center_freq = 2452 },
{ .center_freq = 2457 },
{ .center_freq = 2462 },
{ .center_freq = 2467 },
{ .center_freq = 2472 },
{ .center_freq = 2484 },
};
static const struct ieee80211_rate hwsim_rates[] = {
{ .bitrate = 10 },
{ .bitrate = 20, .flags = IEEE80211_RATE_SHORT_PREAMBLE },
{ .bitrate = 55, .flags = IEEE80211_RATE_SHORT_PREAMBLE },
{ .bitrate = 110, .flags = IEEE80211_RATE_SHORT_PREAMBLE },
{ .bitrate = 60 },
{ .bitrate = 90 },
{ .bitrate = 120 },
{ .bitrate = 180 },
{ .bitrate = 240 },
{ .bitrate = 360 },
{ .bitrate = 480 },
{ .bitrate = 540 }
};
struct mac80211_hwsim_data {
struct device *dev;
struct ieee80211_supported_band band;
struct ieee80211_channel channels[ARRAY_SIZE(hwsim_channels)];
struct ieee80211_rate rates[ARRAY_SIZE(hwsim_rates)];
struct ieee80211_channel *channel;
int radio_enabled;
unsigned long beacon_int; /* in jiffies unit */
unsigned int rx_filter;
int started;
struct timer_list beacon_timer;
};
struct hwsim_radiotap_hdr {
struct ieee80211_radiotap_header hdr;
u8 rt_flags;
u8 rt_rate;
__le16 rt_channel;
__le16 rt_chbitmask;
} __attribute__ ((packed));
static int hwsim_mon_xmit(struct sk_buff *skb, struct net_device *dev)
{
/* TODO: allow packet injection */
dev_kfree_skb(skb);
return 0;
}
static void mac80211_hwsim_monitor_rx(struct ieee80211_hw *hw,
struct sk_buff *tx_skb)
{
struct mac80211_hwsim_data *data = hw->priv;
struct sk_buff *skb;
struct hwsim_radiotap_hdr *hdr;
u16 flags;
struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx_skb);
struct ieee80211_rate *txrate = ieee80211_get_tx_rate(hw, info);
if (!netif_running(hwsim_mon))
return;
skb = skb_copy_expand(tx_skb, sizeof(*hdr), 0, GFP_ATOMIC);
if (skb == NULL)
return;
hdr = (struct hwsim_radiotap_hdr *) skb_push(skb, sizeof(*hdr));
hdr->hdr.it_version = PKTHDR_RADIOTAP_VERSION;
hdr->hdr.it_pad = 0;
hdr->hdr.it_len = cpu_to_le16(sizeof(*hdr));
hdr->hdr.it_present = cpu_to_le32((1 << IEEE80211_RADIOTAP_FLAGS) |
(1 << IEEE80211_RADIOTAP_RATE) |
(1 << IEEE80211_RADIOTAP_CHANNEL));
hdr->rt_flags = 0;
hdr->rt_rate = txrate->bitrate / 5;
hdr->rt_channel = cpu_to_le16(data->channel->center_freq);
flags = IEEE80211_CHAN_2GHZ;
if (txrate->flags & IEEE80211_RATE_ERP_G)
flags |= IEEE80211_CHAN_OFDM;
else
flags |= IEEE80211_CHAN_CCK;
hdr->rt_chbitmask = cpu_to_le16(flags);
skb->dev = hwsim_mon;
skb_set_mac_header(skb, 0);
skb->ip_summed = CHECKSUM_UNNECESSARY;
skb->pkt_type = PACKET_OTHERHOST;
skb->protocol = htons(ETH_P_802_2);
memset(skb->cb, 0, sizeof(skb->cb));
netif_rx(skb);
}
static int mac80211_hwsim_tx_frame(struct ieee80211_hw *hw,
struct sk_buff *skb)
{
struct mac80211_hwsim_data *data = hw->priv;
int i, ack = 0;
struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
struct ieee80211_rx_status rx_status;
memset(&rx_status, 0, sizeof(rx_status));
/* TODO: set mactime */
rx_status.freq = data->channel->center_freq;
rx_status.band = data->channel->band;
rx_status.rate_idx = info->tx_rate_idx;
/* TODO: simulate signal strength (and optional packet drop) */
/* Copy skb to all enabled radios that are on the current frequency */
for (i = 0; i < hwsim_radio_count; i++) {
struct mac80211_hwsim_data *data2;
struct sk_buff *nskb;
if (hwsim_radios[i] == NULL || hwsim_radios[i] == hw)
continue;
data2 = hwsim_radios[i]->priv;
if (!data2->started || !data2->radio_enabled ||
data->channel->center_freq != data2->channel->center_freq)
continue;
nskb = skb_copy(skb, GFP_ATOMIC);
if (nskb == NULL)
continue;
if (memcmp(hdr->addr1, hwsim_radios[i]->wiphy->perm_addr,
ETH_ALEN) == 0)
ack = 1;
ieee80211_rx_irqsafe(hwsim_radios[i], nskb, &rx_status);
}
return ack;
}
static int mac80211_hwsim_tx(struct ieee80211_hw *hw, struct sk_buff *skb)
{
struct mac80211_hwsim_data *data = hw->priv;
int ack;
struct ieee80211_tx_info *txi;
mac80211_hwsim_monitor_rx(hw, skb);
if (skb->len < 10) {
/* Should not happen; just a sanity check for addr1 use */
dev_kfree_skb(skb);
return NETDEV_TX_OK;
}
if (!data->radio_enabled) {
printk(KERN_DEBUG "%s: dropped TX frame since radio "
"disabled\n", wiphy_name(hw->wiphy));
dev_kfree_skb(skb);
return NETDEV_TX_OK;
}
ack = mac80211_hwsim_tx_frame(hw, skb);
txi = IEEE80211_SKB_CB(skb);
memset(&txi->status, 0, sizeof(txi->status));
if (!(txi->flags & IEEE80211_TX_CTL_NO_ACK)) {
if (ack)
txi->flags |= IEEE80211_TX_STAT_ACK;
else
txi->status.excessive_retries = 1;
}
ieee80211_tx_status_irqsafe(hw, skb);
return NETDEV_TX_OK;
}
static int mac80211_hwsim_start(struct ieee80211_hw *hw)
{
struct mac80211_hwsim_data *data = hw->priv;
printk(KERN_DEBUG "%s:%s\n", wiphy_name(hw->wiphy), __func__);
data->started = 1;
return 0;
}
static void mac80211_hwsim_stop(struct ieee80211_hw *hw)
{
struct mac80211_hwsim_data *data = hw->priv;
data->started = 0;
printk(KERN_DEBUG "%s:%s\n", wiphy_name(hw->wiphy), __func__);
}
static int mac80211_hwsim_add_interface(struct ieee80211_hw *hw,
struct ieee80211_if_init_conf *conf)
{
DECLARE_MAC_BUF(mac);
printk(KERN_DEBUG "%s:%s (type=%d mac_addr=%s)\n",
wiphy_name(hw->wiphy), __func__, conf->type,
print_mac(mac, conf->mac_addr));
return 0;
}
static void mac80211_hwsim_remove_interface(
struct ieee80211_hw *hw, struct ieee80211_if_init_conf *conf)
{
DECLARE_MAC_BUF(mac);
printk(KERN_DEBUG "%s:%s (type=%d mac_addr=%s)\n",
wiphy_name(hw->wiphy), __func__, conf->type,
print_mac(mac, conf->mac_addr));
}
static void mac80211_hwsim_beacon_tx(void *arg, u8 *mac,
struct ieee80211_vif *vif)
{
struct ieee80211_hw *hw = arg;
struct sk_buff *skb;
struct ieee80211_tx_info *info;
if (vif->type != IEEE80211_IF_TYPE_AP)
return;
skb = ieee80211_beacon_get(hw, vif);
if (skb == NULL)
return;
info = IEEE80211_SKB_CB(skb);
mac80211_hwsim_monitor_rx(hw, skb);
mac80211_hwsim_tx_frame(hw, skb);
dev_kfree_skb(skb);
}
static void mac80211_hwsim_beacon(unsigned long arg)
{
struct ieee80211_hw *hw = (struct ieee80211_hw *) arg;
struct mac80211_hwsim_data *data = hw->priv;
if (!data->started || !data->radio_enabled)
return;
ieee80211_iterate_active_interfaces_atomic(
hw, mac80211_hwsim_beacon_tx, hw);
data->beacon_timer.expires = jiffies + data->beacon_int;
add_timer(&data->beacon_timer);
}
static int mac80211_hwsim_config(struct ieee80211_hw *hw,
struct ieee80211_conf *conf)
{
struct mac80211_hwsim_data *data = hw->priv;
printk(KERN_DEBUG "%s:%s (freq=%d radio_enabled=%d beacon_int=%d)\n",
wiphy_name(hw->wiphy), __func__,
conf->channel->center_freq, conf->radio_enabled,
conf->beacon_int);
data->channel = conf->channel;
data->radio_enabled = conf->radio_enabled;
data->beacon_int = 1024 * conf->beacon_int / 1000 * HZ / 1000;
if (data->beacon_int < 1)
data->beacon_int = 1;
if (!data->started || !data->radio_enabled)
del_timer(&data->beacon_timer);
else
mod_timer(&data->beacon_timer, jiffies + data->beacon_int);
return 0;
}
static void mac80211_hwsim_configure_filter(struct ieee80211_hw *hw,
unsigned int changed_flags,
unsigned int *total_flags,
int mc_count,
struct dev_addr_list *mc_list)
{
struct mac80211_hwsim_data *data = hw->priv;
printk(KERN_DEBUG "%s:%s\n", wiphy_name(hw->wiphy), __func__);
data->rx_filter = 0;
if (*total_flags & FIF_PROMISC_IN_BSS)
data->rx_filter |= FIF_PROMISC_IN_BSS;
if (*total_flags & FIF_ALLMULTI)
data->rx_filter |= FIF_ALLMULTI;
*total_flags = data->rx_filter;
}
static const struct ieee80211_ops mac80211_hwsim_ops =
{
.tx = mac80211_hwsim_tx,
.start = mac80211_hwsim_start,
.stop = mac80211_hwsim_stop,
.add_interface = mac80211_hwsim_add_interface,
.remove_interface = mac80211_hwsim_remove_interface,
.config = mac80211_hwsim_config,
.configure_filter = mac80211_hwsim_configure_filter,
};
static void mac80211_hwsim_free(void)
{
int i;
for (i = 0; i < hwsim_radio_count; i++) {
if (hwsim_radios[i]) {
struct mac80211_hwsim_data *data;
data = hwsim_radios[i]->priv;
ieee80211_unregister_hw(hwsim_radios[i]);
device_unregister(data->dev);
ieee80211_free_hw(hwsim_radios[i]);
}
}
kfree(hwsim_radios);
class_destroy(hwsim_class);
}
static struct device_driver mac80211_hwsim_driver = {
.name = "mac80211_hwsim"
};
static void hwsim_mon_setup(struct net_device *dev)
{
dev->hard_start_xmit = hwsim_mon_xmit;
dev->destructor = free_netdev;
ether_setup(dev);
dev->tx_queue_len = 0;
dev->type = ARPHRD_IEEE80211_RADIOTAP;
memset(dev->dev_addr, 0, ETH_ALEN);
dev->dev_addr[0] = 0x12;
}
static int __init init_mac80211_hwsim(void)
{
int i, err = 0;
u8 addr[ETH_ALEN];
struct mac80211_hwsim_data *data;
struct ieee80211_hw *hw;
DECLARE_MAC_BUF(mac);
if (radios < 1 || radios > 65535)
return -EINVAL;
hwsim_radio_count = radios;
hwsim_radios = kcalloc(hwsim_radio_count,
sizeof(struct ieee80211_hw *), GFP_KERNEL);
if (hwsim_radios == NULL)
return -ENOMEM;
hwsim_class = class_create(THIS_MODULE, "mac80211_hwsim");
if (IS_ERR(hwsim_class)) {
kfree(hwsim_radios);
return PTR_ERR(hwsim_class);
}
memset(addr, 0, ETH_ALEN);
addr[0] = 0x02;
for (i = 0; i < hwsim_radio_count; i++) {
printk(KERN_DEBUG "mac80211_hwsim: Initializing radio %d\n",
i);
hw = ieee80211_alloc_hw(sizeof(*data), &mac80211_hwsim_ops);
if (hw == NULL) {
printk(KERN_DEBUG "mac80211_hwsim: ieee80211_alloc_hw "
"failed\n");
err = -ENOMEM;
goto failed;
}
hwsim_radios[i] = hw;
data = hw->priv;
data->dev = device_create_drvdata(hwsim_class, NULL, 0, hw,
"hwsim%d", i);
if (IS_ERR(data->dev)) {
printk(KERN_DEBUG
"mac80211_hwsim: device_create_drvdata "
"failed (%ld)\n", PTR_ERR(data->dev));
err = -ENOMEM;
goto failed_drvdata;
}
data->dev->driver = &mac80211_hwsim_driver;
SET_IEEE80211_DEV(hw, data->dev);
addr[3] = i >> 8;
addr[4] = i;
SET_IEEE80211_PERM_ADDR(hw, addr);
hw->channel_change_time = 1;
hw->queues = 1;
memcpy(data->channels, hwsim_channels, sizeof(hwsim_channels));
memcpy(data->rates, hwsim_rates, sizeof(hwsim_rates));
data->band.channels = data->channels;
data->band.n_channels = ARRAY_SIZE(hwsim_channels);
data->band.bitrates = data->rates;
data->band.n_bitrates = ARRAY_SIZE(hwsim_rates);
hw->wiphy->bands[IEEE80211_BAND_2GHZ] = &data->band;
err = ieee80211_register_hw(hw);
if (err < 0) {
printk(KERN_DEBUG "mac80211_hwsim: "
"ieee80211_register_hw failed (%d)\n", err);
goto failed_hw;
}
printk(KERN_DEBUG "%s: hwaddr %s registered\n",
wiphy_name(hw->wiphy),
print_mac(mac, hw->wiphy->perm_addr));
setup_timer(&data->beacon_timer, mac80211_hwsim_beacon,
(unsigned long) hw);
}
hwsim_mon = alloc_netdev(0, "hwsim%d", hwsim_mon_setup);
if (hwsim_mon == NULL)
goto failed;
rtnl_lock();
err = dev_alloc_name(hwsim_mon, hwsim_mon->name);
if (err < 0)
goto failed_mon;
err = register_netdevice(hwsim_mon);
if (err < 0)
goto failed_mon;
rtnl_unlock();
return 0;
failed_mon:
rtnl_unlock();
free_netdev(hwsim_mon);
mac80211_hwsim_free();
return err;
failed_hw:
device_unregister(data->dev);
failed_drvdata:
ieee80211_free_hw(hw);
hwsim_radios[i] = 0;
failed:
mac80211_hwsim_free();
return err;
}
static void __exit exit_mac80211_hwsim(void)
{
printk(KERN_DEBUG "mac80211_hwsim: unregister %d radios\n",
hwsim_radio_count);
unregister_netdev(hwsim_mon);
mac80211_hwsim_free();
}
module_init(init_mac80211_hwsim);
module_exit(exit_mac80211_hwsim);