kernel-ark/net/wireless/wext-sme.c
Johannes Berg f9f475292d cfg80211: always check for scan end on P2P device
If a P2P device wdev is removed while it has a scan, then the
scan completion might crash later as it is already freed by
that time. To avoid the crash always check the scan completion
when the P2P device is being removed for some reason. If the
driver already canceled it, don't want and free it, otherwise
warn and leak it to avoid later crashes.

In order to do this, locking needs to be changed away from the
rdev mutex (which can't always be guaranteed). For now, use
the sched_scan_mtx instead, I'll rename it to just scan_mtx in
a later patch.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2013-03-24 11:15:58 +01:00

434 lines
9.9 KiB
C

/*
* cfg80211 wext compat for managed mode.
*
* Copyright 2009 Johannes Berg <johannes@sipsolutions.net>
* Copyright (C) 2009 Intel Corporation. All rights reserved.
*/
#include <linux/export.h>
#include <linux/etherdevice.h>
#include <linux/if_arp.h>
#include <linux/slab.h>
#include <net/cfg80211.h>
#include <net/cfg80211-wext.h>
#include "wext-compat.h"
#include "nl80211.h"
int cfg80211_mgd_wext_connect(struct cfg80211_registered_device *rdev,
struct wireless_dev *wdev)
{
struct cfg80211_cached_keys *ck = NULL;
const u8 *prev_bssid = NULL;
int err, i;
ASSERT_RDEV_LOCK(rdev);
ASSERT_WDEV_LOCK(wdev);
if (!netif_running(wdev->netdev))
return 0;
wdev->wext.connect.ie = wdev->wext.ie;
wdev->wext.connect.ie_len = wdev->wext.ie_len;
/* Use default background scan period */
wdev->wext.connect.bg_scan_period = -1;
if (wdev->wext.keys) {
wdev->wext.keys->def = wdev->wext.default_key;
wdev->wext.keys->defmgmt = wdev->wext.default_mgmt_key;
if (wdev->wext.default_key != -1)
wdev->wext.connect.privacy = true;
}
if (!wdev->wext.connect.ssid_len)
return 0;
if (wdev->wext.keys) {
ck = kmemdup(wdev->wext.keys, sizeof(*ck), GFP_KERNEL);
if (!ck)
return -ENOMEM;
for (i = 0; i < 6; i++)
ck->params[i].key = ck->data[i];
}
if (wdev->wext.prev_bssid_valid)
prev_bssid = wdev->wext.prev_bssid;
err = __cfg80211_connect(rdev, wdev->netdev,
&wdev->wext.connect, ck, prev_bssid);
if (err)
kfree(ck);
return err;
}
int cfg80211_mgd_wext_siwfreq(struct net_device *dev,
struct iw_request_info *info,
struct iw_freq *wextfreq, char *extra)
{
struct wireless_dev *wdev = dev->ieee80211_ptr;
struct cfg80211_registered_device *rdev = wiphy_to_dev(wdev->wiphy);
struct ieee80211_channel *chan = NULL;
int err, freq;
/* call only for station! */
if (WARN_ON(wdev->iftype != NL80211_IFTYPE_STATION))
return -EINVAL;
freq = cfg80211_wext_freq(wdev->wiphy, wextfreq);
if (freq < 0)
return freq;
if (freq) {
chan = ieee80211_get_channel(wdev->wiphy, freq);
if (!chan)
return -EINVAL;
if (chan->flags & IEEE80211_CHAN_DISABLED)
return -EINVAL;
}
cfg80211_lock_rdev(rdev);
mutex_lock(&rdev->devlist_mtx);
mutex_lock(&rdev->sched_scan_mtx);
wdev_lock(wdev);
if (wdev->sme_state != CFG80211_SME_IDLE) {
bool event = true;
if (wdev->wext.connect.channel == chan) {
err = 0;
goto out;
}
/* if SSID set, we'll try right again, avoid event */
if (wdev->wext.connect.ssid_len)
event = false;
err = __cfg80211_disconnect(rdev, dev,
WLAN_REASON_DEAUTH_LEAVING, event);
if (err)
goto out;
}
wdev->wext.connect.channel = chan;
/*
* SSID is not set, we just want to switch monitor channel,
* this is really just backward compatibility, if the SSID
* is set then we use the channel to select the BSS to use
* to connect to instead. If we were connected on another
* channel we disconnected above and reconnect below.
*/
if (chan && !wdev->wext.connect.ssid_len) {
struct cfg80211_chan_def chandef = {
.width = NL80211_CHAN_WIDTH_20_NOHT,
.center_freq1 = freq,
};
chandef.chan = ieee80211_get_channel(&rdev->wiphy, freq);
if (chandef.chan)
err = cfg80211_set_monitor_channel(rdev, &chandef);
else
err = -EINVAL;
goto out;
}
err = cfg80211_mgd_wext_connect(rdev, wdev);
out:
wdev_unlock(wdev);
mutex_unlock(&rdev->sched_scan_mtx);
mutex_unlock(&rdev->devlist_mtx);
cfg80211_unlock_rdev(rdev);
return err;
}
int cfg80211_mgd_wext_giwfreq(struct net_device *dev,
struct iw_request_info *info,
struct iw_freq *freq, char *extra)
{
struct wireless_dev *wdev = dev->ieee80211_ptr;
struct ieee80211_channel *chan = NULL;
/* call only for station! */
if (WARN_ON(wdev->iftype != NL80211_IFTYPE_STATION))
return -EINVAL;
wdev_lock(wdev);
if (wdev->current_bss)
chan = wdev->current_bss->pub.channel;
else if (wdev->wext.connect.channel)
chan = wdev->wext.connect.channel;
wdev_unlock(wdev);
if (chan) {
freq->m = chan->center_freq;
freq->e = 6;
return 0;
}
/* no channel if not joining */
return -EINVAL;
}
int cfg80211_mgd_wext_siwessid(struct net_device *dev,
struct iw_request_info *info,
struct iw_point *data, char *ssid)
{
struct wireless_dev *wdev = dev->ieee80211_ptr;
struct cfg80211_registered_device *rdev = wiphy_to_dev(wdev->wiphy);
size_t len = data->length;
int err;
/* call only for station! */
if (WARN_ON(wdev->iftype != NL80211_IFTYPE_STATION))
return -EINVAL;
if (!data->flags)
len = 0;
/* iwconfig uses nul termination in SSID.. */
if (len > 0 && ssid[len - 1] == '\0')
len--;
cfg80211_lock_rdev(rdev);
mutex_lock(&rdev->devlist_mtx);
mutex_lock(&rdev->sched_scan_mtx);
wdev_lock(wdev);
err = 0;
if (wdev->sme_state != CFG80211_SME_IDLE) {
bool event = true;
if (wdev->wext.connect.ssid && len &&
len == wdev->wext.connect.ssid_len &&
memcmp(wdev->wext.connect.ssid, ssid, len) == 0)
goto out;
/* if SSID set now, we'll try to connect, avoid event */
if (len)
event = false;
err = __cfg80211_disconnect(rdev, dev,
WLAN_REASON_DEAUTH_LEAVING, event);
if (err)
goto out;
}
wdev->wext.prev_bssid_valid = false;
wdev->wext.connect.ssid = wdev->wext.ssid;
memcpy(wdev->wext.ssid, ssid, len);
wdev->wext.connect.ssid_len = len;
wdev->wext.connect.crypto.control_port = false;
wdev->wext.connect.crypto.control_port_ethertype =
cpu_to_be16(ETH_P_PAE);
err = cfg80211_mgd_wext_connect(rdev, wdev);
out:
wdev_unlock(wdev);
mutex_unlock(&rdev->sched_scan_mtx);
mutex_unlock(&rdev->devlist_mtx);
cfg80211_unlock_rdev(rdev);
return err;
}
int cfg80211_mgd_wext_giwessid(struct net_device *dev,
struct iw_request_info *info,
struct iw_point *data, char *ssid)
{
struct wireless_dev *wdev = dev->ieee80211_ptr;
/* call only for station! */
if (WARN_ON(wdev->iftype != NL80211_IFTYPE_STATION))
return -EINVAL;
data->flags = 0;
wdev_lock(wdev);
if (wdev->current_bss) {
const u8 *ie;
rcu_read_lock();
ie = ieee80211_bss_get_ie(&wdev->current_bss->pub,
WLAN_EID_SSID);
if (ie) {
data->flags = 1;
data->length = ie[1];
memcpy(ssid, ie + 2, data->length);
}
rcu_read_unlock();
} else if (wdev->wext.connect.ssid && wdev->wext.connect.ssid_len) {
data->flags = 1;
data->length = wdev->wext.connect.ssid_len;
memcpy(ssid, wdev->wext.connect.ssid, data->length);
}
wdev_unlock(wdev);
return 0;
}
int cfg80211_mgd_wext_siwap(struct net_device *dev,
struct iw_request_info *info,
struct sockaddr *ap_addr, char *extra)
{
struct wireless_dev *wdev = dev->ieee80211_ptr;
struct cfg80211_registered_device *rdev = wiphy_to_dev(wdev->wiphy);
u8 *bssid = ap_addr->sa_data;
int err;
/* call only for station! */
if (WARN_ON(wdev->iftype != NL80211_IFTYPE_STATION))
return -EINVAL;
if (ap_addr->sa_family != ARPHRD_ETHER)
return -EINVAL;
/* automatic mode */
if (is_zero_ether_addr(bssid) || is_broadcast_ether_addr(bssid))
bssid = NULL;
cfg80211_lock_rdev(rdev);
mutex_lock(&rdev->devlist_mtx);
mutex_lock(&rdev->sched_scan_mtx);
wdev_lock(wdev);
if (wdev->sme_state != CFG80211_SME_IDLE) {
err = 0;
/* both automatic */
if (!bssid && !wdev->wext.connect.bssid)
goto out;
/* fixed already - and no change */
if (wdev->wext.connect.bssid && bssid &&
ether_addr_equal(bssid, wdev->wext.connect.bssid))
goto out;
err = __cfg80211_disconnect(rdev, dev,
WLAN_REASON_DEAUTH_LEAVING, false);
if (err)
goto out;
}
if (bssid) {
memcpy(wdev->wext.bssid, bssid, ETH_ALEN);
wdev->wext.connect.bssid = wdev->wext.bssid;
} else
wdev->wext.connect.bssid = NULL;
err = cfg80211_mgd_wext_connect(rdev, wdev);
out:
wdev_unlock(wdev);
mutex_unlock(&rdev->sched_scan_mtx);
mutex_unlock(&rdev->devlist_mtx);
cfg80211_unlock_rdev(rdev);
return err;
}
int cfg80211_mgd_wext_giwap(struct net_device *dev,
struct iw_request_info *info,
struct sockaddr *ap_addr, char *extra)
{
struct wireless_dev *wdev = dev->ieee80211_ptr;
/* call only for station! */
if (WARN_ON(wdev->iftype != NL80211_IFTYPE_STATION))
return -EINVAL;
ap_addr->sa_family = ARPHRD_ETHER;
wdev_lock(wdev);
if (wdev->current_bss)
memcpy(ap_addr->sa_data, wdev->current_bss->pub.bssid, ETH_ALEN);
else
memset(ap_addr->sa_data, 0, ETH_ALEN);
wdev_unlock(wdev);
return 0;
}
int cfg80211_wext_siwgenie(struct net_device *dev,
struct iw_request_info *info,
struct iw_point *data, char *extra)
{
struct wireless_dev *wdev = dev->ieee80211_ptr;
struct cfg80211_registered_device *rdev = wiphy_to_dev(wdev->wiphy);
u8 *ie = extra;
int ie_len = data->length, err;
if (wdev->iftype != NL80211_IFTYPE_STATION)
return -EOPNOTSUPP;
if (!ie_len)
ie = NULL;
wdev_lock(wdev);
/* no change */
err = 0;
if (wdev->wext.ie_len == ie_len &&
memcmp(wdev->wext.ie, ie, ie_len) == 0)
goto out;
if (ie_len) {
ie = kmemdup(extra, ie_len, GFP_KERNEL);
if (!ie) {
err = -ENOMEM;
goto out;
}
} else
ie = NULL;
kfree(wdev->wext.ie);
wdev->wext.ie = ie;
wdev->wext.ie_len = ie_len;
if (wdev->sme_state != CFG80211_SME_IDLE) {
err = __cfg80211_disconnect(rdev, dev,
WLAN_REASON_DEAUTH_LEAVING, false);
if (err)
goto out;
}
/* userspace better not think we'll reconnect */
err = 0;
out:
wdev_unlock(wdev);
return err;
}
int cfg80211_wext_siwmlme(struct net_device *dev,
struct iw_request_info *info,
struct iw_point *data, char *extra)
{
struct wireless_dev *wdev = dev->ieee80211_ptr;
struct iw_mlme *mlme = (struct iw_mlme *)extra;
struct cfg80211_registered_device *rdev;
int err;
if (!wdev)
return -EOPNOTSUPP;
rdev = wiphy_to_dev(wdev->wiphy);
if (wdev->iftype != NL80211_IFTYPE_STATION)
return -EINVAL;
if (mlme->addr.sa_family != ARPHRD_ETHER)
return -EINVAL;
wdev_lock(wdev);
switch (mlme->cmd) {
case IW_MLME_DEAUTH:
case IW_MLME_DISASSOC:
err = __cfg80211_disconnect(rdev, dev, mlme->reason_code,
true);
break;
default:
err = -EOPNOTSUPP;
break;
}
wdev_unlock(wdev);
return err;
}