Commit d4e50c59 authored by Michal Kazior's avatar Michal Kazior Committed by Johannes Berg
Browse files

cfg80211: add channel checking for iface combinations 



.connect cannot be handled since the driver scans
and connects on its own. It is up to the driver
then to refuse a connection (with -EBUSY for
example).

Non-fixed channel IBSSes always take a single
channel resource. For example two non-fixed
channel IBSSes always take up 2
num_different_channels, even if they operate on
the same channel at a given point of time.

Signed-off-by: default avatarMichal Kazior <michal.kazior@tieto.com>
Signed-off-by: default avatarJohannes Berg <johannes.berg@intel.com>
parent 2e165b81

net/wireless/core.c

+8 −0
Original line number Diff line number Diff line
@@ -373,6 +373,14 @@ static int wiphy_verify_combinations(struct wiphy *wiphy) 
		if (WARN_ON(!c->num_different_channels))

			return -EINVAL;



		/*

		 * Put a sane limit on maximum number of different

		 * channels to simplify channel accounting code.

		 */

		if (WARN_ON(c->num_different_channels >

				CFG80211_MAX_NUM_DIFFERENT_CHANNELS))

			return -EINVAL;



		if (WARN_ON(!c->n_limits))

			return -EINVAL;

net/wireless/core.h

+26 −3
Original line number Diff line number Diff line
@@ -428,9 +428,20 @@ int cfg80211_change_iface(struct cfg80211_registered_device *rdev, 
			  u32 *flags, struct vif_params *params);

void cfg80211_process_rdev_events(struct cfg80211_registered_device *rdev);



int cfg80211_can_change_interface(struct cfg80211_registered_device *rdev,

int cfg80211_can_use_iftype_chan(struct cfg80211_registered_device *rdev,

				 struct wireless_dev *wdev,

				  enum nl80211_iftype iftype);

				 enum nl80211_iftype iftype,

				 struct ieee80211_channel *chan,

				 enum cfg80211_chan_mode chanmode);



static inline int

cfg80211_can_change_interface(struct cfg80211_registered_device *rdev,

			      struct wireless_dev *wdev,

			      enum nl80211_iftype iftype)

{

	return cfg80211_can_use_iftype_chan(rdev, wdev, iftype, NULL,

					    CHAN_MODE_UNDEFINED);

}



static inline int

cfg80211_can_add_interface(struct cfg80211_registered_device *rdev,
@@ -439,6 +450,16 @@ cfg80211_can_add_interface(struct cfg80211_registered_device *rdev, 
	return cfg80211_can_change_interface(rdev, NULL, iftype);

}



static inline int

cfg80211_can_use_chan(struct cfg80211_registered_device *rdev,

		      struct wireless_dev *wdev,

		      struct ieee80211_channel *chan,

		      enum cfg80211_chan_mode chanmode)

{

	return cfg80211_can_use_iftype_chan(rdev, wdev, wdev->iftype,

					    chan, chanmode);

}



void

cfg80211_get_chan_state(struct cfg80211_registered_device *rdev,

		        struct wireless_dev *wdev,
@@ -461,6 +482,8 @@ int cfg80211_validate_beacon_int(struct cfg80211_registered_device *rdev, 
void cfg80211_update_iface_num(struct cfg80211_registered_device *rdev,

			       enum nl80211_iftype iftype, int num);



#define CFG80211_MAX_NUM_DIFFERENT_CHANNELS 10



#ifdef CONFIG_CFG80211_DEVELOPER_WARNINGS

#define CFG80211_DEV_WARN_ON(cond)	WARN_ON(cond)

#else

net/wireless/util.c

+54 −5
Original line number Diff line number Diff line
@@ -938,13 +938,20 @@ int cfg80211_validate_beacon_int(struct cfg80211_registered_device *rdev, 
	return res;

}



int cfg80211_can_change_interface(struct cfg80211_registered_device *rdev,

int cfg80211_can_use_iftype_chan(struct cfg80211_registered_device *rdev,

				 struct wireless_dev *wdev,

				  enum nl80211_iftype iftype)

				 enum nl80211_iftype iftype,

				 struct ieee80211_channel *chan,

				 enum cfg80211_chan_mode chanmode)

{

	struct wireless_dev *wdev_iter;

	u32 used_iftypes = BIT(iftype);

	int num[NUM_NL80211_IFTYPES];

	struct ieee80211_channel

			*used_channels[CFG80211_MAX_NUM_DIFFERENT_CHANNELS];

	struct ieee80211_channel *ch;

	enum cfg80211_chan_mode chmode;

	int num_different_channels = 0;

	int total = 1;

	int i, j;
@@ -955,9 +962,23 @@ int cfg80211_can_change_interface(struct cfg80211_registered_device *rdev, 
		return 0;



	memset(num, 0, sizeof(num));

	memset(used_channels, 0, sizeof(used_channels));



	num[iftype] = 1;



	switch (chanmode) {

	case CHAN_MODE_UNDEFINED:

		break;

	case CHAN_MODE_SHARED:

		WARN_ON(!chan);

		used_channels[0] = chan;

		num_different_channels++;

		break;

	case CHAN_MODE_EXCLUSIVE:

		num_different_channels++;

		break;

	}



	mutex_lock(&rdev->devlist_mtx);

	list_for_each_entry(wdev_iter, &rdev->netdev_list, list) {

		if (wdev_iter == wdev)
@@ -968,6 +989,31 @@ int cfg80211_can_change_interface(struct cfg80211_registered_device *rdev, 
		if (rdev->wiphy.software_iftypes & BIT(wdev_iter->iftype))

			continue;



		cfg80211_get_chan_state(rdev, wdev_iter, &ch, &chmode);



		switch (chmode) {

		case CHAN_MODE_UNDEFINED:

			break;

		case CHAN_MODE_SHARED:

			for (i = 0; i < CFG80211_MAX_NUM_DIFFERENT_CHANNELS; i++)

				if (!used_channels[i] || used_channels[i] == ch)

					break;



			if (i == CFG80211_MAX_NUM_DIFFERENT_CHANNELS) {

				mutex_unlock(&rdev->devlist_mtx);

				return -EBUSY;

			}



			if (used_channels[i] == NULL) {

				used_channels[i] = ch;

				num_different_channels++;

			}

			break;

		case CHAN_MODE_EXCLUSIVE:

			num_different_channels++;

			break;

		}



		num[wdev_iter->iftype]++;

		total++;

		used_iftypes |= BIT(wdev_iter->iftype);
@@ -984,12 +1030,15 @@ int cfg80211_can_change_interface(struct cfg80211_registered_device *rdev, 


		c = &rdev->wiphy.iface_combinations[i];



		if (total > c->max_interfaces)

			continue;

		if (num_different_channels > c->num_different_channels)

			continue;



		limits = kmemdup(c->limits, sizeof(limits[0]) * c->n_limits,

				 GFP_KERNEL);

		if (!limits)

			return -ENOMEM;

		if (total > c->max_interfaces)

			goto cont;



		for (iftype = 0; iftype < NUM_NL80211_IFTYPES; iftype++) {

			if (rdev->wiphy.software_iftypes & BIT(iftype))

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