Commit 0256317a authored by Jakub Kicinski's avatar Jakub Kicinski
Browse files

Merge tag 'mac80211-next-for-net-next-2021-02-02' of... 

Merge tag 'mac80211-next-for-net-next-2021-02-02' of git://git.kernel.org/pub/scm/linux/kernel/git/jberg/mac80211-next

Johannes Berg says:

====================
This time, only RTNL locking reduction fallout.
 - cfg80211_dev_rename() requires RTNL
 - cfg80211_change_iface() and cfg80211_set_encryption()
   require wiphy mutex (was missing in wireless extensions)
 - cfg80211_destroy_ifaces() requires wiphy mutex
 - netdev registration can fail due to notifiers, and then
   notifiers are "unrolled", need to handle this properly

* tag 'mac80211-next-for-net-next-2021-02-02' of git://git.kernel.org/pub/scm/linux/kernel/git/jberg/mac80211-next:
  cfg80211: fix netdev registration deadlock
  cfg80211: call cfg80211_destroy_ifaces() with wiphy lock held
  wext: call cfg80211_set_encryption() with wiphy lock held
  wext: call cfg80211_change_iface() with wiphy lock held
  nl80211: call cfg80211_dev_rename() under RTNL
====================

Link: https://lore.kernel.org/r/20210202144106.38207-1-johannes@sipsolutions.net


Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
parents 390d9b56 40c575d1

include/net/cfg80211.h

+3 −1
Original line number Diff line number Diff line
@@ -5299,6 +5299,8 @@ static inline void wiphy_unlock(struct wiphy *wiphy) 
 * @wiphy: pointer to hardware description

 * @iftype: interface type

 * @registered: is this wdev already registered with cfg80211

 * @registering: indicates we're doing registration under wiphy lock

 *	for the notifier

 * @list: (private) Used to collect the interfaces

 * @netdev: (private) Used to reference back to the netdev, may be %NULL

 * @identifier: (private) Identifier used in nl80211 to identify this
@@ -5382,7 +5384,7 @@ struct wireless_dev { 


	struct mutex mtx;



	bool use_4addr, is_running, registered;

	bool use_4addr, is_running, registered, registering;



	u8 address[ETH_ALEN] __aligned(sizeof(u16));

net/wireless/core.c

+6 −1
Original line number Diff line number Diff line
@@ -334,6 +334,7 @@ void cfg80211_destroy_ifaces(struct cfg80211_registered_device *rdev) 
	struct wireless_dev *wdev, *tmp;



	ASSERT_RTNL();

	lockdep_assert_wiphy(&rdev->wiphy);



	list_for_each_entry_safe(wdev, tmp, &rdev->wiphy.wdev_list, list) {

		if (wdev->nl_owner_dead)
@@ -349,7 +350,9 @@ static void cfg80211_destroy_iface_wk(struct work_struct *work) 
			    destroy_work);



	rtnl_lock();

	wiphy_lock(&rdev->wiphy);

	cfg80211_destroy_ifaces(rdev);

	wiphy_unlock(&rdev->wiphy);

	rtnl_unlock();

}
@@ -1343,6 +1346,7 @@ int cfg80211_register_netdevice(struct net_device *dev) 


	/* we'll take care of this */

	wdev->registered = true;

	wdev->registering = true;

	ret = register_netdevice(dev);

	if (ret)

		goto out;
@@ -1358,6 +1362,7 @@ int cfg80211_register_netdevice(struct net_device *dev) 
	cfg80211_register_wdev(rdev, wdev);

	ret = 0;

out:

	wdev->registering = false;

	if (ret)

		wdev->registered = false;

	return ret;
@@ -1400,7 +1405,7 @@ static int cfg80211_netdev_notifier_call(struct notifier_block *nb, 
		 * It is possible to get NETDEV_UNREGISTER multiple times,

		 * so check wdev->registered.

		 */

		if (wdev->registered) {

		if (wdev->registered && !wdev->registering) {

			wiphy_lock(&rdev->wiphy);

			_cfg80211_unregister_wdev(wdev, false);

			wiphy_unlock(&rdev->wiphy);

net/wireless/nl80211.c

+1 −1
Original line number Diff line number Diff line
@@ -3220,7 +3220,6 @@ static int nl80211_set_wiphy(struct sk_buff *skb, struct genl_info *info) 
		wdev = netdev->ieee80211_ptr;



	wiphy_lock(&rdev->wiphy);

	rtnl_unlock();



	/*

	 * end workaround code, by now the rdev is available
@@ -3230,6 +3229,7 @@ static int nl80211_set_wiphy(struct sk_buff *skb, struct genl_info *info) 
	if (info->attrs[NL80211_ATTR_WIPHY_NAME])

		result = cfg80211_dev_rename(

			rdev, nla_data(info->attrs[NL80211_ATTR_WIPHY_NAME]));

	rtnl_unlock();



	if (result)

		goto out;

net/wireless/wext-compat.c

+12 −2
Original line number Diff line number Diff line
@@ -39,6 +39,7 @@ int cfg80211_wext_siwmode(struct net_device *dev, struct iw_request_info *info, 
	struct cfg80211_registered_device *rdev;

	struct vif_params vifparams;

	enum nl80211_iftype type;

	int ret;



	rdev = wiphy_to_rdev(wdev->wiphy);
@@ -61,7 +62,11 @@ int cfg80211_wext_siwmode(struct net_device *dev, struct iw_request_info *info, 


	memset(&vifparams, 0, sizeof(vifparams));



	return cfg80211_change_iface(rdev, dev, type, &vifparams);

	wiphy_lock(wdev->wiphy);

	ret = cfg80211_change_iface(rdev, dev, type, &vifparams);

	wiphy_unlock(wdev->wiphy);



	return ret;

}

EXPORT_WEXT_HANDLER(cfg80211_wext_siwmode);
@@ -650,6 +655,7 @@ static int cfg80211_wext_siwencodeext(struct net_device *dev, 
	bool remove = false;

	struct key_params params;

	u32 cipher;

	int ret;



	if (wdev->iftype != NL80211_IFTYPE_STATION &&

	    wdev->iftype != NL80211_IFTYPE_ADHOC)
@@ -721,12 +727,16 @@ static int cfg80211_wext_siwencodeext(struct net_device *dev, 
		params.seq_len = 6;

	}



	return cfg80211_set_encryption(

	wiphy_lock(wdev->wiphy);

	ret = cfg80211_set_encryption(

			rdev, dev,

			!(ext->ext_flags & IW_ENCODE_EXT_GROUP_KEY),

			addr, remove,

			ext->ext_flags & IW_ENCODE_EXT_SET_TX_KEY,

			idx, &params);

	wiphy_unlock(wdev->wiphy);



	return ret;

}



static int cfg80211_wext_giwencode(struct net_device *dev,