cfg80211/mac80211/ath6kl: acquire wdev lock outside ch_switch_notify

The channel switch notification should be sent under the
wdev/sdata-lock, preferably in the same moment as the channel change
happens, to avoid races by other callers (e.g. start/stop_ap).
This also adds the previously missing sdata_lock protection in
csa_finalize_work.

Reported-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
This commit is contained in:
Simon Wunderlich 2013-11-21 18:19:51 +01:00 committed by Johannes Berg
parent 7ca133bc7f
commit e487eaeb07
4 changed files with 22 additions and 13 deletions

View File

@ -1109,7 +1109,9 @@ void ath6kl_cfg80211_ch_switch_notify(struct ath6kl_vif *vif, int freq,
(mode == WMI_11G_HT20) ?
NL80211_CHAN_HT20 : NL80211_CHAN_NO_HT);
mutex_lock(&vif->wdev.mtx);
cfg80211_ch_switch_notify(vif->ndev, &chandef);
mutex_unlock(&vif->wdev.mtx);
}
static int ath6kl_cfg80211_add_key(struct wiphy *wiphy, struct net_device *ndev,

View File

@ -4286,7 +4286,8 @@ bool cfg80211_reg_can_beacon(struct wiphy *wiphy,
* @dev: the device which switched channels
* @chandef: the new channel definition
*
* Acquires wdev_lock, so must only be called from sleepable driver context!
* Caller must acquire wdev_lock, therefore must only be called from sleepable
* driver context!
*/
void cfg80211_ch_switch_notify(struct net_device *dev,
struct cfg80211_chan_def *chandef);

View File

@ -2988,13 +2988,18 @@ void ieee80211_csa_finalize_work(struct work_struct *work)
struct ieee80211_local *local = sdata->local;
int err, changed = 0;
sdata_lock(sdata);
/* AP might have been stopped while waiting for the lock. */
if (!sdata->vif.csa_active)
goto unlock;
if (!ieee80211_sdata_running(sdata))
return;
goto unlock;
sdata->radar_required = sdata->csa_radar_required;
err = ieee80211_vif_change_channel(sdata, &changed);
if (WARN_ON(err < 0))
return;
goto unlock;
if (!local->use_chanctx) {
local->_oper_chandef = sdata->csa_chandef;
@ -3003,11 +3008,13 @@ void ieee80211_csa_finalize_work(struct work_struct *work)
ieee80211_bss_info_change_notify(sdata, changed);
sdata->vif.csa_active = false;
switch (sdata->vif.type) {
case NL80211_IFTYPE_AP:
err = ieee80211_assign_beacon(sdata, sdata->u.ap.next_beacon);
if (err < 0)
return;
goto unlock;
changed |= err;
kfree(sdata->u.ap.next_beacon);
sdata->u.ap.next_beacon = NULL;
@ -3021,20 +3028,22 @@ void ieee80211_csa_finalize_work(struct work_struct *work)
case NL80211_IFTYPE_MESH_POINT:
err = ieee80211_mesh_finish_csa(sdata);
if (err < 0)
return;
goto unlock;
break;
#endif
default:
WARN_ON(1);
return;
goto unlock;
}
sdata->vif.csa_active = false;
ieee80211_wake_queues_by_reason(&sdata->local->hw,
IEEE80211_MAX_QUEUE_MAP,
IEEE80211_QUEUE_STOP_REASON_CSA);
cfg80211_ch_switch_notify(sdata->dev, &sdata->csa_chandef);
unlock:
sdata_unlock(sdata);
}
static int ieee80211_channel_switch(struct wiphy *wiphy, struct net_device *dev,

View File

@ -10821,21 +10821,18 @@ void cfg80211_ch_switch_notify(struct net_device *dev,
struct wiphy *wiphy = wdev->wiphy;
struct cfg80211_registered_device *rdev = wiphy_to_dev(wiphy);
trace_cfg80211_ch_switch_notify(dev, chandef);
ASSERT_WDEV_LOCK(wdev);
wdev_lock(wdev);
trace_cfg80211_ch_switch_notify(dev, chandef);
if (WARN_ON(wdev->iftype != NL80211_IFTYPE_AP &&
wdev->iftype != NL80211_IFTYPE_P2P_GO &&
wdev->iftype != NL80211_IFTYPE_ADHOC &&
wdev->iftype != NL80211_IFTYPE_MESH_POINT))
goto out;
return;
wdev->channel = chandef->chan;
nl80211_ch_switch_notify(rdev, dev, chandef, GFP_KERNEL);
out:
wdev_unlock(wdev);
return;
}
EXPORT_SYMBOL(cfg80211_ch_switch_notify);