[PATCH] softmac: Fix WX and association related races
This fixes some race conditions in the WirelessExtension
handling and association handling code.
Signed-off-by: Michael Buesch <mb@bu3sch.de>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/drivers/net/wireless/bcm43xx/bcm43xx_leds.c b/drivers/net/wireless/bcm43xx/bcm43xx_leds.c
index c3f90c8..2ddbec6 100644
--- a/drivers/net/wireless/bcm43xx/bcm43xx_leds.c
+++ b/drivers/net/wireless/bcm43xx/bcm43xx_leds.c
@@ -242,7 +242,7 @@
//TODO
break;
case BCM43xx_LED_ASSOC:
- if (bcm->softmac->associated)
+ if (bcm->softmac->associnfo.associated)
turn_on = 1;
break;
#ifdef CONFIG_BCM43XX_DEBUG
diff --git a/drivers/net/wireless/bcm43xx/bcm43xx_wx.c b/drivers/net/wireless/bcm43xx/bcm43xx_wx.c
index 9b7b15c..d27016f 100644
--- a/drivers/net/wireless/bcm43xx/bcm43xx_wx.c
+++ b/drivers/net/wireless/bcm43xx/bcm43xx_wx.c
@@ -847,7 +847,7 @@
unsigned long flags;
wstats = &bcm->stats.wstats;
- if (!mac->associated) {
+ if (!mac->associnfo.associated) {
wstats->miss.beacon = 0;
// bcm->ieee->ieee_stats.tx_retry_limit_exceeded = 0; // FIXME: should this be cleared here?
wstats->discard.retries = 0;
diff --git a/include/net/ieee80211softmac.h b/include/net/ieee80211softmac.h
index 425b3a5..617b672 100644
--- a/include/net/ieee80211softmac.h
+++ b/include/net/ieee80211softmac.h
@@ -63,13 +63,11 @@
/*
* Information about association
- *
- * Do we need a lock for this?
- * We only ever use this structure inlined
- * into our global struct. I've used its lock,
- * but maybe we need a local one here?
*/
struct ieee80211softmac_assoc_info {
+
+ struct mutex mutex;
+
/*
* This is the requested ESSID. It is written
* only by the WX handlers.
@@ -99,12 +97,13 @@
*
* bssfixed is used for SIOCSIWAP.
*/
- u8 static_essid:1,
- short_preamble_available:1,
- associating:1,
- assoc_wait:1,
- bssvalid:1,
- bssfixed:1;
+ u8 static_essid;
+ u8 short_preamble_available;
+ u8 associating;
+ u8 associated;
+ u8 assoc_wait;
+ u8 bssvalid;
+ u8 bssfixed;
/* Scan retries remaining */
int scan_retry;
@@ -229,12 +228,10 @@
/* private stuff follows */
/* this lock protects this structure */
spinlock_t lock;
-
- /* couple of flags */
- u8 scanning:1, /* protects scanning from being done multiple times at once */
- associated:1,
- running:1;
-
+
+ u8 running; /* SoftMAC started? */
+ u8 scanning;
+
struct ieee80211softmac_scaninfo *scaninfo;
struct ieee80211softmac_assoc_info associnfo;
struct ieee80211softmac_bss_info bssinfo;
@@ -250,7 +247,7 @@
/* we need to keep a list of network structs we copied */
struct list_head network_list;
-
+
/* This must be the last item so that it points to the data
* allocated beyond this structure by alloc_ieee80211 */
u8 priv[0];
@@ -295,7 +292,7 @@
{
struct ieee80211softmac_txrates *txrates = &mac->txrates;
- if (!mac->associated)
+ if (!mac->associnfo.associated)
return txrates->mgt_mcast_rate;
/* We are associated, sending unicast frame */
diff --git a/net/ieee80211/softmac/ieee80211softmac_assoc.c b/net/ieee80211/softmac/ieee80211softmac_assoc.c
index 589f6d2..cf51c87 100644
--- a/net/ieee80211/softmac/ieee80211softmac_assoc.c
+++ b/net/ieee80211/softmac/ieee80211softmac_assoc.c
@@ -48,7 +48,7 @@
dprintk(KERN_INFO PFX "sent association request!\n");
spin_lock_irqsave(&mac->lock, flags);
- mac->associated = 0; /* just to make sure */
+ mac->associnfo.associated = 0; /* just to make sure */
/* Set a timer for timeout */
/* FIXME: make timeout configurable */
@@ -62,24 +62,22 @@
{
struct ieee80211softmac_device *mac = (struct ieee80211softmac_device *)d;
struct ieee80211softmac_network *n;
- unsigned long flags;
- spin_lock_irqsave(&mac->lock, flags);
+ mutex_lock(&mac->associnfo.mutex);
/* we might race against ieee80211softmac_handle_assoc_response,
* so make sure only one of us does something */
- if (!mac->associnfo.associating) {
- spin_unlock_irqrestore(&mac->lock, flags);
- return;
- }
+ if (!mac->associnfo.associating)
+ goto out;
mac->associnfo.associating = 0;
mac->associnfo.bssvalid = 0;
- mac->associated = 0;
+ mac->associnfo.associated = 0;
n = ieee80211softmac_get_network_by_bssid_locked(mac, mac->associnfo.bssid);
- spin_unlock_irqrestore(&mac->lock, flags);
dprintk(KERN_INFO PFX "assoc request timed out!\n");
ieee80211softmac_call_events(mac, IEEE80211SOFTMAC_EVENT_ASSOCIATE_TIMEOUT, n);
+out:
+ mutex_unlock(&mac->associnfo.mutex);
}
void
@@ -93,7 +91,7 @@
netif_carrier_off(mac->dev);
- mac->associated = 0;
+ mac->associnfo.associated = 0;
mac->associnfo.bssvalid = 0;
mac->associnfo.associating = 0;
ieee80211softmac_init_bss(mac);
@@ -107,7 +105,7 @@
{
struct ieee80211softmac_network *found;
- if (mac->associnfo.bssvalid && mac->associated) {
+ if (mac->associnfo.bssvalid && mac->associnfo.associated) {
found = ieee80211softmac_get_network_by_bssid(mac, mac->associnfo.bssid);
if (found)
ieee80211softmac_send_mgt_frame(mac, found, IEEE80211_STYPE_DISASSOC, reason);
@@ -196,17 +194,18 @@
int bssvalid;
unsigned long flags;
+ mutex_lock(&mac->associnfo.mutex);
+
+ if (!mac->associnfo.associating)
+ goto out;
+
/* ieee80211_disassoc might clear this */
bssvalid = mac->associnfo.bssvalid;
/* meh */
- if (mac->associated)
+ if (mac->associnfo.associated)
ieee80211softmac_send_disassoc_req(mac, WLAN_REASON_DISASSOC_STA_HAS_LEFT);
- spin_lock_irqsave(&mac->lock, flags);
- mac->associnfo.associating = 1;
- spin_unlock_irqrestore(&mac->lock, flags);
-
/* try to find the requested network in our list, if we found one already */
if (bssvalid || mac->associnfo.bssfixed)
found = ieee80211softmac_get_network_by_bssid(mac, mac->associnfo.bssid);
@@ -260,10 +259,8 @@
if (!found) {
if (mac->associnfo.scan_retry > 0) {
- spin_lock_irqsave(&mac->lock, flags);
mac->associnfo.scan_retry--;
- spin_unlock_irqrestore(&mac->lock, flags);
-
+
/* We know of no such network. Let's scan.
* NB: this also happens if we had no memory to copy the network info...
* Maybe we can hope to have more memory after scanning finishes ;)
@@ -272,19 +269,17 @@
ieee80211softmac_notify(mac->dev, IEEE80211SOFTMAC_EVENT_SCAN_FINISHED, ieee80211softmac_assoc_notify_scan, NULL);
if (ieee80211softmac_start_scan(mac))
dprintk(KERN_INFO PFX "Associate: failed to initiate scan. Is device up?\n");
- return;
+ goto out;
} else {
- spin_lock_irqsave(&mac->lock, flags);
mac->associnfo.associating = 0;
- mac->associated = 0;
- spin_unlock_irqrestore(&mac->lock, flags);
+ mac->associnfo.associated = 0;
dprintk(KERN_INFO PFX "Unable to find matching network after scan!\n");
/* reset the retry counter for the next user request since we
* break out and don't reschedule ourselves after this point. */
mac->associnfo.scan_retry = IEEE80211SOFTMAC_ASSOC_SCAN_RETRY_LIMIT;
ieee80211softmac_call_events(mac, IEEE80211SOFTMAC_EVENT_ASSOCIATE_NET_NOT_FOUND, NULL);
- return;
+ goto out;
}
}
@@ -297,7 +292,7 @@
/* copy the ESSID for displaying it */
mac->associnfo.associate_essid.len = found->essid.len;
memcpy(mac->associnfo.associate_essid.data, found->essid.data, IW_ESSID_MAX_SIZE + 1);
-
+
/* we found a network! authenticate (if necessary) and associate to it. */
if (found->authenticating) {
dprintk(KERN_INFO PFX "Already requested authentication, waiting...\n");
@@ -305,7 +300,7 @@
mac->associnfo.assoc_wait = 1;
ieee80211softmac_notify_internal(mac, IEEE80211SOFTMAC_EVENT_ANY, found, ieee80211softmac_assoc_notify_auth, NULL, GFP_KERNEL);
}
- return;
+ goto out;
}
if (!found->authenticated && !found->authenticating) {
/* This relies on the fact that _auth_req only queues the work,
@@ -321,11 +316,14 @@
mac->associnfo.assoc_wait = 0;
ieee80211softmac_call_events(mac, IEEE80211SOFTMAC_EVENT_ASSOCIATE_FAILED, found);
}
- return;
+ goto out;
}
/* finally! now we can start associating */
mac->associnfo.assoc_wait = 0;
ieee80211softmac_assoc(mac, found);
+
+out:
+ mutex_unlock(&mac->associnfo.mutex);
}
/* call this to do whatever is necessary when we're associated */
@@ -341,7 +339,7 @@
mac->bssinfo.supported_rates = net->supported_rates;
ieee80211softmac_recalc_txrates(mac);
- mac->associated = 1;
+ mac->associnfo.associated = 1;
mac->associnfo.short_preamble_available =
(cap & WLAN_CAPABILITY_SHORT_PREAMBLE) != 0;
@@ -421,7 +419,7 @@
dprintk(KERN_INFO PFX "associating failed (reason: 0x%x)!\n", status);
mac->associnfo.associating = 0;
mac->associnfo.bssvalid = 0;
- mac->associated = 0;
+ mac->associnfo.associated = 0;
ieee80211softmac_call_events_locked(mac, IEEE80211SOFTMAC_EVENT_ASSOCIATE_FAILED, network);
}
diff --git a/net/ieee80211/softmac/ieee80211softmac_io.c b/net/ieee80211/softmac/ieee80211softmac_io.c
index 82bfddb..e8419cf 100644
--- a/net/ieee80211/softmac/ieee80211softmac_io.c
+++ b/net/ieee80211/softmac/ieee80211softmac_io.c
@@ -475,8 +475,13 @@
{
struct ieee80211softmac_device *mac = ieee80211_priv(dev);
- if (mac->associated && memcmp(network->bssid, mac->associnfo.bssid, ETH_ALEN) == 0)
- ieee80211softmac_process_erp(mac, network->erp_value);
+ /* This might race, but we don't really care and it's not worth
+ * adding heavyweight locking in this fastpath.
+ */
+ if (mac->associnfo.associated) {
+ if (memcmp(network->bssid, mac->associnfo.bssid, ETH_ALEN) == 0)
+ ieee80211softmac_process_erp(mac, network->erp_value);
+ }
return 0;
}
diff --git a/net/ieee80211/softmac/ieee80211softmac_module.c b/net/ieee80211/softmac/ieee80211softmac_module.c
index addea1c..33aff4f 100644
--- a/net/ieee80211/softmac/ieee80211softmac_module.c
+++ b/net/ieee80211/softmac/ieee80211softmac_module.c
@@ -57,6 +57,7 @@
INIT_LIST_HEAD(&softmac->network_list);
INIT_LIST_HEAD(&softmac->events);
+ mutex_init(&softmac->associnfo.mutex);
INIT_WORK(&softmac->associnfo.work, ieee80211softmac_assoc_work, softmac);
INIT_WORK(&softmac->associnfo.timeout, ieee80211softmac_assoc_timeout, softmac);
softmac->start_scan = ieee80211softmac_start_scan_implementation;
diff --git a/net/ieee80211/softmac/ieee80211softmac_wx.c b/net/ieee80211/softmac/ieee80211softmac_wx.c
index 2aa779d..23068a8 100644
--- a/net/ieee80211/softmac/ieee80211softmac_wx.c
+++ b/net/ieee80211/softmac/ieee80211softmac_wx.c
@@ -73,13 +73,14 @@
struct ieee80211softmac_network *n;
struct ieee80211softmac_auth_queue_item *authptr;
int length = 0;
- unsigned long flags;
+
+ mutex_lock(&sm->associnfo.mutex);
/* Check if we're already associating to this or another network
* If it's another network, cancel and start over with our new network
* If it's our network, ignore the change, we're already doing it!
*/
- if((sm->associnfo.associating || sm->associated) &&
+ if((sm->associnfo.associating || sm->associnfo.associated) &&
(data->essid.flags && data->essid.length)) {
/* Get the associating network */
n = ieee80211softmac_get_network_by_bssid(sm, sm->associnfo.bssid);
@@ -87,10 +88,9 @@
!memcmp(n->essid.data, extra, n->essid.len)) {
dprintk(KERN_INFO PFX "Already associating or associated to "MAC_FMT"\n",
MAC_ARG(sm->associnfo.bssid));
- return 0;
+ goto out;
} else {
dprintk(KERN_INFO PFX "Canceling existing associate request!\n");
- spin_lock_irqsave(&sm->lock,flags);
/* Cancel assoc work */
cancel_delayed_work(&sm->associnfo.work);
/* We don't have to do this, but it's a little cleaner */
@@ -98,14 +98,13 @@
cancel_delayed_work(&authptr->work);
sm->associnfo.bssvalid = 0;
sm->associnfo.bssfixed = 0;
- spin_unlock_irqrestore(&sm->lock,flags);
flush_scheduled_work();
+ sm->associnfo.associating = 0;
+ sm->associnfo.associated = 0;
}
}
- spin_lock_irqsave(&sm->lock, flags);
-
sm->associnfo.static_essid = 0;
sm->associnfo.assoc_wait = 0;
@@ -121,10 +120,12 @@
* If applicable, we have already copied the data in */
sm->associnfo.req_essid.len = length;
+ sm->associnfo.associating = 1;
/* queue lower level code to do work (if necessary) */
schedule_work(&sm->associnfo.work);
+out:
+ mutex_unlock(&sm->associnfo.mutex);
- spin_unlock_irqrestore(&sm->lock, flags);
return 0;
}
EXPORT_SYMBOL_GPL(ieee80211softmac_wx_set_essid);
@@ -136,10 +137,8 @@
char *extra)
{
struct ieee80211softmac_device *sm = ieee80211_priv(net_dev);
- unsigned long flags;
- /* avoid getting inconsistent information */
- spin_lock_irqsave(&sm->lock, flags);
+ mutex_lock(&sm->associnfo.mutex);
/* If all fails, return ANY (empty) */
data->essid.length = 0;
data->essid.flags = 0; /* active */
@@ -152,12 +151,13 @@
}
/* If we're associating/associated, return that */
- if (sm->associated || sm->associnfo.associating) {
+ if (sm->associnfo.associated || sm->associnfo.associating) {
data->essid.length = sm->associnfo.associate_essid.len;
data->essid.flags = 1; /* active */
memcpy(extra, sm->associnfo.associate_essid.data, sm->associnfo.associate_essid.len);
}
- spin_unlock_irqrestore(&sm->lock, flags);
+ mutex_unlock(&sm->associnfo.mutex);
+
return 0;
}
EXPORT_SYMBOL_GPL(ieee80211softmac_wx_get_essid);
@@ -322,15 +322,15 @@
{
struct ieee80211softmac_device *mac = ieee80211_priv(net_dev);
int err = 0;
- unsigned long flags;
- spin_lock_irqsave(&mac->lock, flags);
+ mutex_lock(&mac->associnfo.mutex);
if (mac->associnfo.bssvalid)
memcpy(data->ap_addr.sa_data, mac->associnfo.bssid, ETH_ALEN);
else
memset(data->ap_addr.sa_data, 0xff, ETH_ALEN);
data->ap_addr.sa_family = ARPHRD_ETHER;
- spin_unlock_irqrestore(&mac->lock, flags);
+ mutex_unlock(&mac->associnfo.mutex);
+
return err;
}
EXPORT_SYMBOL_GPL(ieee80211softmac_wx_get_wap);
@@ -342,28 +342,27 @@
char *extra)
{
struct ieee80211softmac_device *mac = ieee80211_priv(net_dev);
- unsigned long flags;
/* sanity check */
if (data->ap_addr.sa_family != ARPHRD_ETHER) {
return -EINVAL;
}
- spin_lock_irqsave(&mac->lock, flags);
+ mutex_lock(&mac->associnfo.mutex);
if (is_broadcast_ether_addr(data->ap_addr.sa_data)) {
/* the bssid we have is not to be fixed any longer,
* and we should reassociate to the best AP. */
mac->associnfo.bssfixed = 0;
/* force reassociation */
mac->associnfo.bssvalid = 0;
- if (mac->associated)
+ if (mac->associnfo.associated)
schedule_work(&mac->associnfo.work);
} else if (is_zero_ether_addr(data->ap_addr.sa_data)) {
/* the bssid we have is no longer fixed */
mac->associnfo.bssfixed = 0;
} else {
if (!memcmp(mac->associnfo.bssid, data->ap_addr.sa_data, ETH_ALEN)) {
- if (mac->associnfo.associating || mac->associated) {
+ if (mac->associnfo.associating || mac->associnfo.associated) {
/* bssid unchanged and associated or associating - just return */
goto out;
}
@@ -378,7 +377,8 @@
}
out:
- spin_unlock_irqrestore(&mac->lock, flags);
+ mutex_unlock(&mac->associnfo.mutex);
+
return 0;
}
EXPORT_SYMBOL_GPL(ieee80211softmac_wx_set_wap);
@@ -394,7 +394,8 @@
int err = 0;
char *buf;
int i;
-
+
+ mutex_lock(&mac->associnfo.mutex);
spin_lock_irqsave(&mac->lock, flags);
/* bleh. shouldn't be locked for that kmalloc... */
@@ -432,6 +433,8 @@
out:
spin_unlock_irqrestore(&mac->lock, flags);
+ mutex_unlock(&mac->associnfo.mutex);
+
return err;
}
EXPORT_SYMBOL_GPL(ieee80211softmac_wx_set_genie);
@@ -446,7 +449,8 @@
unsigned long flags;
int err = 0;
int space = wrqu->data.length;
-
+
+ mutex_lock(&mac->associnfo.mutex);
spin_lock_irqsave(&mac->lock, flags);
wrqu->data.length = 0;
@@ -459,6 +463,8 @@
err = -E2BIG;
}
spin_unlock_irqrestore(&mac->lock, flags);
+ mutex_lock(&mac->associnfo.mutex);
+
return err;
}
EXPORT_SYMBOL_GPL(ieee80211softmac_wx_get_genie);
@@ -473,10 +479,13 @@
struct iw_mlme *mlme = (struct iw_mlme *)extra;
u16 reason = cpu_to_le16(mlme->reason_code);
struct ieee80211softmac_network *net;
+ int err = -EINVAL;
+
+ mutex_lock(&mac->associnfo.mutex);
if (memcmp(mac->associnfo.bssid, mlme->addr.sa_data, ETH_ALEN)) {
printk(KERN_DEBUG PFX "wx_set_mlme: requested operation on net we don't use\n");
- return -EINVAL;
+ goto out;
}
switch (mlme->cmd) {
@@ -484,14 +493,22 @@
net = ieee80211softmac_get_network_by_bssid_locked(mac, mlme->addr.sa_data);
if (!net) {
printk(KERN_DEBUG PFX "wx_set_mlme: we should know the net here...\n");
- return -EINVAL;
+ goto out;
}
return ieee80211softmac_deauth_req(mac, net, reason);
case IW_MLME_DISASSOC:
ieee80211softmac_send_disassoc_req(mac, reason);
- return 0;
+ mac->associnfo.associated = 0;
+ mac->associnfo.associating = 0;
+ err = 0;
+ goto out;
default:
- return -EOPNOTSUPP;
+ err = -EOPNOTSUPP;
}
+
+out:
+ mutex_unlock(&mac->associnfo.mutex);
+
+ return err;
}
EXPORT_SYMBOL_GPL(ieee80211softmac_wx_set_mlme);