cfg80211: allow registering more than one beacon listener

The commit: commit 5e760230e42cf759bd923457ca2753aacf2e656e Author: Johannes Berg <johannes.berg@intel.com> Date: Fri Nov 4 11:18:17 2011 +0100 cfg80211: allow registering to beacons allowed only a single process to register for beacon events per wiphy. This breaks cases where a user may want two or more VIFs on a wiphy and run a seperate hostapd process on each vif. This patch allows multiple beacon listeners, fixing the regression. Signed-off-by: Ben Greear <greearb@candelatech.com> Signed-off-by: Johannes Berg <johannes.berg@intel.com>

cfg80211: allow registering more than one beacon listener
The commit: commit 5e760230e42cf759bd923457ca2753aacf2e656e Author: Johannes Berg <johannes.berg@intel.com> Date: Fri Nov 4 11:18:17 2011 +0100 cfg80211: allow registering to beacons allowed only a single process to register for beacon events per wiphy. This breaks cases where a user may want two or more VIFs on a wiphy and run a seperate hostapd process on each vif. This patch allows multiple beacon listeners, fixing the regression. Signed-off-by: Ben Greear <greearb@candelatech.com> Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Ben Greear · Johannes Berg
1 parent 391e53e33f
Showing 5 changed files with 75 additions and 32 deletions Side-by-side Diff
include/net/cfg80211.h
net/mac80211/rx.c
net/wireless/core.c
net/wireless/core.h
net/wireless/nl80211.c
@@ -3560,7 +3560,6 @@
  * @len: length of the frame
  * @freq: frequency the frame was received on
  * @sig_dbm: signal strength in mBm, or 0 if unknown
- * @gfp: allocation flags
  *
  * Use this function to report to userspace when a beacon was
  * received. It is not useful to call this when there is no
@@ -3568,7 +3567,7 @@
  */
 void cfg80211_report_obss_beacon(struct wiphy *wiphy,
 				 const u8 *frame, size_t len,
-				 int freq, int sig_dbm, gfp_t gfp);
+				 int freq, int sig_dbm);
  
 /**
  * cfg80211_can_beacon_sec_chan - test if ht40 on extension channel can be used
@@ -2200,7 +2200,7 @@
  
 		cfg80211_report_obss_beacon(rx->local->hw.wiphy,
 					    rx->skb->data, rx->skb->len,
-					    status->freq, sig, GFP_ATOMIC);
+					    status->freq, sig);
 		rx->flags |= IEEE80211_RX_BEACON_REPORTED;
 	}
  
@@ -326,6 +326,8 @@
 	mutex_init(&rdev->devlist_mtx);
 	mutex_init(&rdev->sched_scan_mtx);
 	INIT_LIST_HEAD(&rdev->wdev_list);
+	INIT_LIST_HEAD(&rdev->beacon_registrations);
+	spin_lock_init(&rdev->beacon_registrations_lock);
 	spin_lock_init(&rdev->bss_lock);
 	INIT_LIST_HEAD(&rdev->bss_list);
 	INIT_WORK(&rdev->scan_done_wk, __cfg80211_scan_done);
  
@@ -698,10 +700,15 @@
 void cfg80211_dev_free(struct cfg80211_registered_device *rdev)
 {
 	struct cfg80211_internal_bss *scan, *tmp;
+	struct cfg80211_beacon_registration *reg, *treg;
 	rfkill_destroy(rdev->rfkill);
 	mutex_destroy(&rdev->mtx);
 	mutex_destroy(&rdev->devlist_mtx);
 	mutex_destroy(&rdev->sched_scan_mtx);
+	list_for_each_entry_safe(reg, treg, &rdev->beacon_registrations, list) {
+		list_del(&reg->list);
+		kfree(reg);
+	}
 	list_for_each_entry_safe(scan, tmp, &rdev->bss_list, list)
 		cfg80211_put_bss(&scan->pub);
 	kfree(rdev);
@@ -55,7 +55,8 @@
 	int opencount; /* also protected by devlist_mtx */
 	wait_queue_head_t dev_wait;
  
-	u32 ap_beacons_nlportid;
+	struct list_head beacon_registrations;
+	spinlock_t beacon_registrations_lock;
  
 	/* protected by RTNL only */
 	int num_running_ifaces;
@@ -260,6 +261,10 @@
 	CHAN_MODE_EXCLUSIVE,
 };
  
+struct cfg80211_beacon_registration {
+	struct list_head list;
+	u32 nlportid;
+};
  
 /* free object */
 extern void cfg80211_dev_free(struct cfg80211_registered_device *rdev);
@@ -6934,16 +6934,35 @@
 static int nl80211_register_beacons(struct sk_buff *skb, struct genl_info *info)
 {
 	struct cfg80211_registered_device *rdev = info->user_ptr[0];
+	struct cfg80211_beacon_registration *reg, *nreg;
+	int rv;
  
 	if (!(rdev->wiphy.flags & WIPHY_FLAG_REPORTS_OBSS))
 		return -EOPNOTSUPP;
  
-	if (rdev->ap_beacons_nlportid)
-		return -EBUSY;
+	nreg = kzalloc(sizeof(*nreg), GFP_KERNEL);
+	if (!nreg)
+		return -ENOMEM;
  
-	rdev->ap_beacons_nlportid = info->snd_portid;
+	/* First, check if already registered. */
+	spin_lock_bh(&rdev->beacon_registrations_lock);
+	list_for_each_entry(reg, &rdev->beacon_registrations, list) {
+		if (reg->nlportid == info->snd_portid) {
+			rv = -EALREADY;
+			goto out_err;
+		}
+	}
+	/* Add it to the list */
+	nreg->nlportid = info->snd_portid;
+	list_add(&nreg->list, &rdev->beacon_registrations);
  
+	spin_unlock_bh(&rdev->beacon_registrations_lock);
+
 	return 0;
+out_err:
+	spin_unlock_bh(&rdev->beacon_registrations_lock);
+	kfree(nreg);
+	return rv;
 }
  
 static int nl80211_start_p2p_device(struct sk_buff *skb, struct genl_info *info)
  
  
  
  
  
  
  
@@ -8957,43 +8976,46 @@
  
 void cfg80211_report_obss_beacon(struct wiphy *wiphy,
 				 const u8 *frame, size_t len,
-				 int freq, int sig_dbm, gfp_t gfp)
+				 int freq, int sig_dbm)
 {
 	struct cfg80211_registered_device *rdev = wiphy_to_dev(wiphy);
 	struct sk_buff *msg;
 	void *hdr;
-	u32 nlportid = ACCESS_ONCE(rdev->ap_beacons_nlportid);
+	struct cfg80211_beacon_registration *reg;
  
 	trace_cfg80211_report_obss_beacon(wiphy, frame, len, freq, sig_dbm);
  
-	if (!nlportid)
-		return;
+	spin_lock_bh(&rdev->beacon_registrations_lock);
+	list_for_each_entry(reg, &rdev->beacon_registrations, list) {
+		msg = nlmsg_new(len + 100, GFP_ATOMIC);
+		if (!msg) {
+			spin_unlock_bh(&rdev->beacon_registrations_lock);
+			return;
+		}
  
-	msg = nlmsg_new(len + 100, gfp);
-	if (!msg)
-		return;
+		hdr = nl80211hdr_put(msg, 0, 0, 0, NL80211_CMD_FRAME);
+		if (!hdr)
+			goto nla_put_failure;
  
-	hdr = nl80211hdr_put(msg, 0, 0, 0, NL80211_CMD_FRAME);
-	if (!hdr) {
-		nlmsg_free(msg);
-		return;
-	}
+		if (nla_put_u32(msg, NL80211_ATTR_WIPHY, rdev->wiphy_idx) ||
+		    (freq &&
+		     nla_put_u32(msg, NL80211_ATTR_WIPHY_FREQ, freq)) ||
+		    (sig_dbm &&
+		     nla_put_u32(msg, NL80211_ATTR_RX_SIGNAL_DBM, sig_dbm)) ||
+		    nla_put(msg, NL80211_ATTR_FRAME, len, frame))
+			goto nla_put_failure;
  
-	if (nla_put_u32(msg, NL80211_ATTR_WIPHY, rdev->wiphy_idx) ||
-	    (freq &&
-	     nla_put_u32(msg, NL80211_ATTR_WIPHY_FREQ, freq)) ||
-	    (sig_dbm &&
-	     nla_put_u32(msg, NL80211_ATTR_RX_SIGNAL_DBM, sig_dbm)) ||
-	    nla_put(msg, NL80211_ATTR_FRAME, len, frame))
-		goto nla_put_failure;
+		genlmsg_end(msg, hdr);
  
-	genlmsg_end(msg, hdr);
-
-	genlmsg_unicast(wiphy_net(&rdev->wiphy), msg, nlportid);
+		genlmsg_unicast(wiphy_net(&rdev->wiphy), msg, reg->nlportid);
+	}
+	spin_unlock_bh(&rdev->beacon_registrations_lock);
 	return;
  
  nla_put_failure:
-	genlmsg_cancel(msg, hdr);
+	spin_unlock_bh(&rdev->beacon_registrations_lock);
+	if (hdr)
+		genlmsg_cancel(msg, hdr);
 	nlmsg_free(msg);
 }
 EXPORT_SYMBOL(cfg80211_report_obss_beacon);
@@ -9005,6 +9027,7 @@
 	struct netlink_notify *notify = _notify;
 	struct cfg80211_registered_device *rdev;
 	struct wireless_dev *wdev;
+	struct cfg80211_beacon_registration *reg, *tmp;
  
 	if (state != NETLINK_URELEASE)
 		return NOTIFY_DONE;
@@ -9014,8 +9037,17 @@
 	list_for_each_entry_rcu(rdev, &cfg80211_rdev_list, list) {
 		list_for_each_entry_rcu(wdev, &rdev->wdev_list, list)
 			cfg80211_mlme_unregister_socket(wdev, notify->portid);
-		if (rdev->ap_beacons_nlportid == notify->portid)
-			rdev->ap_beacons_nlportid = 0;
+
+		spin_lock_bh(&rdev->beacon_registrations_lock);
+		list_for_each_entry_safe(reg, tmp, &rdev->beacon_registrations,
+					 list) {
+			if (reg->nlportid == notify->portid) {
+				list_del(&reg->list);
+				kfree(reg);
+				break;
+			}
+		}
+		spin_unlock_bh(&rdev->beacon_registrations_lock);
 	}
  
 	rcu_read_unlock();
...	...	@@ -3560,7 +3560,6 @@
3560	3560	* @len: length of the frame
3561	3561	* @freq: frequency the frame was received on
3562	3562	* @sig_dbm: signal strength in mBm, or 0 if unknown
3563		- * @gfp: allocation flags
3564	3563	*
3565	3564	* Use this function to report to userspace when a beacon was
3566	3565	* received. It is not useful to call this when there is no
...	...	@@ -3568,7 +3567,7 @@
3568	3567	*/
3569	3568	void cfg80211_report_obss_beacon(struct wiphy *wiphy,
3570	3569	const u8 *frame, size_t len,
3571		- int freq, int sig_dbm, gfp_t gfp);
	3570	+ int freq, int sig_dbm);
3572	3571
3573	3572	/**
3574	3573	* cfg80211_can_beacon_sec_chan - test if ht40 on extension channel can be used
...	...	@@ -2200,7 +2200,7 @@
2200	2200
2201	2201	cfg80211_report_obss_beacon(rx->local->hw.wiphy,
2202	2202	rx->skb->data, rx->skb->len,
2203		- status->freq, sig, GFP_ATOMIC);
	2203	+ status->freq, sig);
2204	2204	rx->flags \|= IEEE80211_RX_BEACON_REPORTED;
2205	2205	}
2206	2206
...	...	@@ -326,6 +326,8 @@
326	326	mutex_init(&rdev->devlist_mtx);
327	327	mutex_init(&rdev->sched_scan_mtx);
328	328	INIT_LIST_HEAD(&rdev->wdev_list);
	329	+ INIT_LIST_HEAD(&rdev->beacon_registrations);
	330	+ spin_lock_init(&rdev->beacon_registrations_lock);
329	331	spin_lock_init(&rdev->bss_lock);
330	332	INIT_LIST_HEAD(&rdev->bss_list);
331	333	INIT_WORK(&rdev->scan_done_wk, __cfg80211_scan_done);
332	334
...	...	@@ -698,10 +700,15 @@
698	700	void cfg80211_dev_free(struct cfg80211_registered_device *rdev)
699	701	{
700	702	struct cfg80211_internal_bss scan, tmp;
	703	+ struct cfg80211_beacon_registration reg, treg;
701	704	rfkill_destroy(rdev->rfkill);
702	705	mutex_destroy(&rdev->mtx);
703	706	mutex_destroy(&rdev->devlist_mtx);
704	707	mutex_destroy(&rdev->sched_scan_mtx);
	708	+ list_for_each_entry_safe(reg, treg, &rdev->beacon_registrations, list) {
	709	+ list_del(&reg->list);
	710	+ kfree(reg);
	711	+ }
705	712	list_for_each_entry_safe(scan, tmp, &rdev->bss_list, list)
706	713	cfg80211_put_bss(&scan->pub);
707	714	kfree(rdev);
...	...	@@ -55,7 +55,8 @@
55	55	int opencount; /* also protected by devlist_mtx */
56	56	wait_queue_head_t dev_wait;
57	57
58		- u32 ap_beacons_nlportid;
	58	+ struct list_head beacon_registrations;
	59	+ spinlock_t beacon_registrations_lock;
59	60
60	61	/* protected by RTNL only */
61	62	int num_running_ifaces;
...	...	@@ -260,6 +261,10 @@
260	261	CHAN_MODE_EXCLUSIVE,
261	262	};
262	263
	264	+struct cfg80211_beacon_registration {
	265	+ struct list_head list;
	266	+ u32 nlportid;
	267	+};
263	268
264	269	/* free object */
265	270	extern void cfg80211_dev_free(struct cfg80211_registered_device *rdev);
...	...	@@ -6934,16 +6934,35 @@
6934	6934	static int nl80211_register_beacons(struct sk_buff skb, struct genl_info info)
6935	6935	{
6936	6936	struct cfg80211_registered_device *rdev = info->user_ptr[0];
	6937	+ struct cfg80211_beacon_registration reg, nreg;
	6938	+ int rv;
6937	6939
6938	6940	if (!(rdev->wiphy.flags & WIPHY_FLAG_REPORTS_OBSS))
6939	6941	return -EOPNOTSUPP;
6940	6942
6941		- if (rdev->ap_beacons_nlportid)
6942		- return -EBUSY;
	6943	+ nreg = kzalloc(sizeof(*nreg), GFP_KERNEL);
	6944	+ if (!nreg)
	6945	+ return -ENOMEM;
6943	6946
6944		- rdev->ap_beacons_nlportid = info->snd_portid;
	6947	+ /* First, check if already registered. */
	6948	+ spin_lock_bh(&rdev->beacon_registrations_lock);
	6949	+ list_for_each_entry(reg, &rdev->beacon_registrations, list) {
	6950	+ if (reg->nlportid == info->snd_portid) {
	6951	+ rv = -EALREADY;
	6952	+ goto out_err;
	6953	+ }
	6954	+ }
	6955	+ /* Add it to the list */
	6956	+ nreg->nlportid = info->snd_portid;
	6957	+ list_add(&nreg->list, &rdev->beacon_registrations);
6945	6958
	6959	+ spin_unlock_bh(&rdev->beacon_registrations_lock);
	6960	+
6946	6961	return 0;
	6962	+out_err:
	6963	+ spin_unlock_bh(&rdev->beacon_registrations_lock);
	6964	+ kfree(nreg);
	6965	+ return rv;
6947	6966	}
6948	6967
6949	6968	static int nl80211_start_p2p_device(struct sk_buff skb, struct genl_info info)
6950	6969
6951	6970
6952	6971
6953	6972
6954	6973
6955	6974
6956	6975
...	...	@@ -8957,43 +8976,46 @@
8957	8976
8958	8977	void cfg80211_report_obss_beacon(struct wiphy *wiphy,
8959	8978	const u8 *frame, size_t len,
8960		- int freq, int sig_dbm, gfp_t gfp)
	8979	+ int freq, int sig_dbm)
8961	8980	{
8962	8981	struct cfg80211_registered_device *rdev = wiphy_to_dev(wiphy);
8963	8982	struct sk_buff *msg;
8964	8983	void *hdr;
8965		- u32 nlportid = ACCESS_ONCE(rdev->ap_beacons_nlportid);
	8984	+ struct cfg80211_beacon_registration *reg;
8966	8985
8967	8986	trace_cfg80211_report_obss_beacon(wiphy, frame, len, freq, sig_dbm);
8968	8987
8969		- if (!nlportid)
8970		- return;
	8988	+ spin_lock_bh(&rdev->beacon_registrations_lock);
	8989	+ list_for_each_entry(reg, &rdev->beacon_registrations, list) {
	8990	+ msg = nlmsg_new(len + 100, GFP_ATOMIC);
	8991	+ if (!msg) {
	8992	+ spin_unlock_bh(&rdev->beacon_registrations_lock);
	8993	+ return;
	8994	+ }
8971	8995
8972		- msg = nlmsg_new(len + 100, gfp);
8973		- if (!msg)
8974		- return;
	8996	+ hdr = nl80211hdr_put(msg, 0, 0, 0, NL80211_CMD_FRAME);
	8997	+ if (!hdr)
	8998	+ goto nla_put_failure;
8975	8999
8976		- hdr = nl80211hdr_put(msg, 0, 0, 0, NL80211_CMD_FRAME);
8977		- if (!hdr) {
8978		- nlmsg_free(msg);
8979		- return;
8980		- }
	9000	+ if (nla_put_u32(msg, NL80211_ATTR_WIPHY, rdev->wiphy_idx) \|\|
	9001	+ (freq &&
	9002	+ nla_put_u32(msg, NL80211_ATTR_WIPHY_FREQ, freq)) \|\|
	9003	+ (sig_dbm &&
	9004	+ nla_put_u32(msg, NL80211_ATTR_RX_SIGNAL_DBM, sig_dbm)) \|\|
	9005	+ nla_put(msg, NL80211_ATTR_FRAME, len, frame))
	9006	+ goto nla_put_failure;
8981	9007
8982		- if (nla_put_u32(msg, NL80211_ATTR_WIPHY, rdev->wiphy_idx) \|\|
8983		- (freq &&
8984		- nla_put_u32(msg, NL80211_ATTR_WIPHY_FREQ, freq)) \|\|
8985		- (sig_dbm &&
8986		- nla_put_u32(msg, NL80211_ATTR_RX_SIGNAL_DBM, sig_dbm)) \|\|
8987		- nla_put(msg, NL80211_ATTR_FRAME, len, frame))
8988		- goto nla_put_failure;
	9008	+ genlmsg_end(msg, hdr);
8989	9009
8990		- genlmsg_end(msg, hdr);
8991		-
8992		- genlmsg_unicast(wiphy_net(&rdev->wiphy), msg, nlportid);
	9010	+ genlmsg_unicast(wiphy_net(&rdev->wiphy), msg, reg->nlportid);
	9011	+ }
	9012	+ spin_unlock_bh(&rdev->beacon_registrations_lock);
8993	9013	return;
8994	9014
8995	9015	nla_put_failure:
8996		- genlmsg_cancel(msg, hdr);
	9016	+ spin_unlock_bh(&rdev->beacon_registrations_lock);
	9017	+ if (hdr)
	9018	+ genlmsg_cancel(msg, hdr);
8997	9019	nlmsg_free(msg);
8998	9020	}
8999	9021	EXPORT_SYMBOL(cfg80211_report_obss_beacon);
...	...	@@ -9005,6 +9027,7 @@
9005	9027	struct netlink_notify *notify = _notify;
9006	9028	struct cfg80211_registered_device *rdev;
9007	9029	struct wireless_dev *wdev;
	9030	+ struct cfg80211_beacon_registration reg, tmp;
9008	9031
9009	9032	if (state != NETLINK_URELEASE)
9010	9033	return NOTIFY_DONE;
...	...	@@ -9014,8 +9037,17 @@
9014	9037	list_for_each_entry_rcu(rdev, &cfg80211_rdev_list, list) {
9015	9038	list_for_each_entry_rcu(wdev, &rdev->wdev_list, list)
9016	9039	cfg80211_mlme_unregister_socket(wdev, notify->portid);
9017		- if (rdev->ap_beacons_nlportid == notify->portid)
9018		- rdev->ap_beacons_nlportid = 0;
	9040	+
	9041	+ spin_lock_bh(&rdev->beacon_registrations_lock);
	9042	+ list_for_each_entry_safe(reg, tmp, &rdev->beacon_registrations,
	9043	+ list) {
	9044	+ if (reg->nlportid == notify->portid) {
	9045	+ list_del(&reg->list);
	9046	+ kfree(reg);
	9047	+ break;
	9048	+ }
	9049	+ }
	9050	+ spin_unlock_bh(&rdev->beacon_registrations_lock);
9019	9051	}
9020	9052
9021	9053	rcu_read_unlock();