Commit d4c4a9a1 authored by Alan Jenkins's avatar Alan Jenkins Committed by John W. Linville
Browse files

mac80211: fix modprobe deadlock by not calling wep_init under rtnl_lock 



- ieee80211_wep_init(), which is called with rtnl_lock held, blocks in
   request_module() [waiting for modprobe to load a crypto module].

 - modprobe blocks in a call to flush_workqueue(), when it closes a TTY
   [presumably when it exits].

 - The workqueue item linkwatch_event() blocks on rtnl_lock.

There's no reason for wep_init() to be called with rtnl_lock held, so
just move it outside the critical section.

Signed-off-by: default avatarAlan Jenkins <alan-jenkins@tuffmail.co.uk>
Signed-off-by: default avatarJohn W. Linville <linville@tuxdriver.com>
parent b7fcb5c4

net/mac80211/main.c

+9 −10
Original line number Diff line number Diff line
@@ -909,6 +909,13 @@ int ieee80211_register_hw(struct ieee80211_hw *hw) 
	if (result < 0)

		goto fail_sta_info;



	result = ieee80211_wep_init(local);

	if (result < 0) {

		printk(KERN_DEBUG "%s: Failed to initialize wep: %d\n",

		       wiphy_name(local->hw.wiphy), result);

		goto fail_wep;

	}



	rtnl_lock();

	result = dev_alloc_name(local->mdev, local->mdev->name);

	if (result < 0)
@@ -930,14 +937,6 @@ int ieee80211_register_hw(struct ieee80211_hw *hw) 
		goto fail_rate;

	}



	result = ieee80211_wep_init(local);



	if (result < 0) {

		printk(KERN_DEBUG "%s: Failed to initialize wep: %d\n",

		       wiphy_name(local->hw.wiphy), result);

		goto fail_wep;

	}



	/* add one default STA interface if supported */

	if (local->hw.wiphy->interface_modes & BIT(NL80211_IFTYPE_STATION)) {

		result = ieee80211_if_add(local, "wlan%d", NULL,
@@ -967,13 +966,13 @@ int ieee80211_register_hw(struct ieee80211_hw *hw) 


	return 0;



fail_wep:

	rate_control_deinitialize(local);

fail_rate:

	unregister_netdevice(local->mdev);

	local->mdev = NULL;

fail_dev:

	rtnl_unlock();

	ieee80211_wep_free(local);

fail_wep:

	sta_info_stop(local);

fail_sta_info:

	debugfs_hw_del(local);

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