From 7c28ad2d83ecc637237fe684659a6afbce0bb2a8 Mon Sep 17 00:00:00 2001 From: Michael Buesch Date: Wed, 27 Sep 2006 15:26:33 +0300 Subject: [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 Signed-off-by: John W. Linville --- net/ieee80211/softmac/ieee80211softmac_assoc.c | 56 ++++++++++--------- net/ieee80211/softmac/ieee80211softmac_io.c | 9 +++- net/ieee80211/softmac/ieee80211softmac_module.c | 1 + net/ieee80211/softmac/ieee80211softmac_wx.c | 71 +++++++++++++++---------- 4 files changed, 79 insertions(+), 58 deletions(-) (limited to 'net/ieee80211/softmac') diff --git a/net/ieee80211/softmac/ieee80211softmac_assoc.c b/net/ieee80211/softmac/ieee80211softmac_assoc.c index 589f6d2c548a..cf51c87a971d 100644 --- a/net/ieee80211/softmac/ieee80211softmac_assoc.c +++ b/net/ieee80211/softmac/ieee80211softmac_assoc.c @@ -48,7 +48,7 @@ ieee80211softmac_assoc(struct ieee80211softmac_device *mac, struct ieee80211soft 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 @@ ieee80211softmac_assoc_timeout(void *d) { 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 @@ ieee80211softmac_disassoc(struct ieee80211softmac_device *mac) 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 @@ ieee80211softmac_send_disassoc_req(struct ieee80211softmac_device *mac, u16 reas { 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 @@ ieee80211softmac_assoc_work(void *d) 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 @@ ieee80211softmac_assoc_work(void *d) 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_assoc_work(void *d) 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 @@ ieee80211softmac_assoc_work(void *d) /* 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 @@ ieee80211softmac_assoc_work(void *d) 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 @@ ieee80211softmac_assoc_work(void *d) 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 @@ ieee80211softmac_associated(struct ieee80211softmac_device *mac, 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 @@ ieee80211softmac_handle_assoc_response(struct net_device * dev, 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 82bfddbf33a2..e8419cfb058f 100644 --- a/net/ieee80211/softmac/ieee80211softmac_io.c +++ b/net/ieee80211/softmac/ieee80211softmac_io.c @@ -475,8 +475,13 @@ int ieee80211softmac_handle_beacon(struct net_device *dev, { 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 addea1cf73ae..33aff4f4a471 100644 --- a/net/ieee80211/softmac/ieee80211softmac_module.c +++ b/net/ieee80211/softmac/ieee80211softmac_module.c @@ -57,6 +57,7 @@ struct net_device *alloc_ieee80211softmac(int sizeof_priv) 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 2aa779d18f38..23068a830f7d 100644 --- a/net/ieee80211/softmac/ieee80211softmac_wx.c +++ b/net/ieee80211/softmac/ieee80211softmac_wx.c @@ -73,13 +73,14 @@ ieee80211softmac_wx_set_essid(struct net_device *net_dev, 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 @@ ieee80211softmac_wx_set_essid(struct net_device *net_dev, !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 @@ ieee80211softmac_wx_set_essid(struct net_device *net_dev, 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 @@ ieee80211softmac_wx_set_essid(struct net_device *net_dev, * 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 @@ ieee80211softmac_wx_get_essid(struct net_device *net_dev, 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 @@ ieee80211softmac_wx_get_essid(struct net_device *net_dev, } /* 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 @@ ieee80211softmac_wx_get_wap(struct net_device *net_dev, { 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 @@ ieee80211softmac_wx_set_wap(struct net_device *net_dev, 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 @@ ieee80211softmac_wx_set_wap(struct net_device *net_dev, } 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 @@ ieee80211softmac_wx_set_genie(struct net_device *dev, 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 @@ ieee80211softmac_wx_set_genie(struct net_device *dev, 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 @@ ieee80211softmac_wx_get_genie(struct net_device *dev, 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 @@ ieee80211softmac_wx_get_genie(struct net_device *dev, 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 @@ ieee80211softmac_wx_set_mlme(struct net_device *dev, 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 @@ ieee80211softmac_wx_set_mlme(struct net_device *dev, 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); -- cgit v1.2.2