linux/net/wireless/wext-sme.c
Johannes Berg a05829a722 cfg80211: avoid holding the RTNL when calling the driver
Currently, _everything_ in cfg80211 holds the RTNL, and if you
have a slow USB device (or a few) you can get some bad lock
contention on that.

Fix that by re-adding a mutex to each wiphy/rdev as we had at
some point, so we have locking for the wireless_dev lists and
all the other things in there, and also so that drivers still
don't have to worry too much about it (they still won't get
parallel calls for a single device).

Then, we can restrict the RTNL to a few cases where we add or
remove interfaces and really need the added protection. Some
of the global list management still also uses the RTNL, since
we need to have it anyway for netdev management, but we only
hold the RTNL for very short periods of time here.

Link: https://lore.kernel.org/r/20210122161942.81df9f5e047a.I4a8e1a60b18863ea8c5e6d3a0faeafb2d45b2f40@changeid
Tested-by: Marek Szyprowski <m.szyprowski@samsung.com> [marvell driver issues]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2021-01-26 11:55:50 +01:00

398 lines
8.8 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* cfg80211 wext compat for managed mode.
*
* Copyright 2009 Johannes Berg <johannes@sipsolutions.net>
* Copyright (C) 2009, 2020-2021 Intel Corporation.
*/
#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_RTNL();
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;
if (wdev->wext.default_key != -1)
wdev->wext.connect.privacy = true;
}
if (!wdev->wext.connect.ssid_len)
return 0;
if (wdev->wext.keys && wdev->wext.keys->def != -1) {
ck = kmemdup(wdev->wext.keys, sizeof(*ck), GFP_KERNEL);
if (!ck)
return -ENOMEM;
for (i = 0; i < CFG80211_MAX_WEP_KEYS; 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_sensitive(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_rdev(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(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;
}
wdev_lock(wdev);
if (wdev->conn) {
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;
err = cfg80211_mgd_wext_connect(rdev, wdev);
out:
wdev_unlock(wdev);
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_rdev(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--;
wdev_lock(wdev);
err = 0;
if (wdev->conn) {
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);
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;
int ret = 0;
/* 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];
if (data->length > IW_ESSID_MAX_SIZE)
ret = -EINVAL;
else
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 ret;
}
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_rdev(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;
wdev_lock(wdev);
if (wdev->conn) {
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);
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
eth_zero_addr(ap_addr->sa_data);
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_rdev(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->conn) {
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_rdev(wdev->wiphy);
if (wdev->iftype != NL80211_IFTYPE_STATION)
return -EINVAL;
if (mlme->addr.sa_family != ARPHRD_ETHER)
return -EINVAL;
wiphy_lock(&rdev->wiphy);
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);
wiphy_unlock(&rdev->wiphy);
return err;
}