Commit 23736995 authored by Miquel Raynal's avatar Miquel Raynal
Browse files

mac802154: Avoid new associations while disassociating 



While disassociating from a PAN ourselves, let's set the maximum number
of associations temporarily to zero to be sure no new device tries to
associate with us.

Signed-off-by: default avatarMiquel Raynal <miquel.raynal@bootlin.com>
Acked-by: default avatarStefan Schmidt <stefan@datenfreihafen.org>
Acked-by: default avatarAlexander Aring <aahringo@redhat.com>
Link: https://lore.kernel.org/linux-wpan/20231128111655.507479-6-miquel.raynal@bootlin.com
parent b720383a

include/net/cfg802154.h

+3 −1
Original line number Diff line number Diff line
@@ -589,8 +589,10 @@ cfg802154_device_is_child(struct wpan_dev *wpan_dev, 
 * cfg802154_set_max_associations - Limit the number of future associations

 * @wpan_dev: the wpan device

 * @max: the maximum number of devices we accept to associate

 * @return: the old maximum value

 */

void cfg802154_set_max_associations(struct wpan_dev *wpan_dev, unsigned int max);

unsigned int cfg802154_set_max_associations(struct wpan_dev *wpan_dev,

					    unsigned int max);



/**

 * cfg802154_get_free_short_addr - Get a free address among the known devices

net/ieee802154/pan.c

+7 −1
Original line number Diff line number Diff line
@@ -94,10 +94,16 @@ __le16 cfg802154_get_free_short_addr(struct wpan_dev *wpan_dev) 
}

EXPORT_SYMBOL_GPL(cfg802154_get_free_short_addr);



void cfg802154_set_max_associations(struct wpan_dev *wpan_dev, unsigned int max)

unsigned int cfg802154_set_max_associations(struct wpan_dev *wpan_dev,

					    unsigned int max)

{

	unsigned int old_max;



	lockdep_assert_held(&wpan_dev->association_lock);



	old_max = wpan_dev->max_associations;

	wpan_dev->max_associations = max;



	return old_max;

}

EXPORT_SYMBOL_GPL(cfg802154_set_max_associations);

net/mac802154/cfg.c

+8 −3
Original line number Diff line number Diff line
@@ -389,6 +389,7 @@ static int mac802154_disassociate_from_parent(struct wpan_phy *wpan_phy, 
	struct ieee802154_local *local = wpan_phy_priv(wpan_phy);

	struct ieee802154_pan_device *child, *tmp;

	struct ieee802154_sub_if_data *sdata;

	unsigned int max_assoc;

	u64 eaddr;

	int ret;
@@ -397,6 +398,7 @@ static int mac802154_disassociate_from_parent(struct wpan_phy *wpan_phy, 
	/* Start by disassociating all the children and preventing new ones to

	 * attempt associations.

	 */

	max_assoc = cfg802154_set_max_associations(wpan_dev, 0);

	list_for_each_entry_safe(child, tmp, &wpan_dev->children, node) {

		ret = mac802154_send_disassociation_notif(sdata, child,

							  IEEE802154_COORD_WISHES_DEVICE_TO_LEAVE);
@@ -429,14 +431,17 @@ static int mac802154_disassociate_from_parent(struct wpan_phy *wpan_phy, 
	if (local->hw.flags & IEEE802154_HW_AFILT) {

		ret = drv_set_pan_id(local, wpan_dev->pan_id);

		if (ret < 0)

			return ret;

			goto reset_mac_assoc;



		ret = drv_set_short_addr(local, wpan_dev->short_addr);

		if (ret < 0)

			return ret;

			goto reset_mac_assoc;

	}



	return 0;

reset_mac_assoc:

	cfg802154_set_max_associations(wpan_dev, max_assoc);



	return ret;

}



static int mac802154_disassociate_child(struct wpan_phy *wpan_phy,