From 133d40f9a22bdfd2617a446f1e3209537c5415ec Mon Sep 17 00:00:00 2001 From: Stanislaw Gruszka Date: Wed, 28 Mar 2012 16:01:19 +0200 Subject: [PATCH] mac80211: do not scan and monitor connection in parallel Before we send probes in connection monitoring we check if scan is not pending. But we do that check without locking. Fix that and also do not start scan if connection monitoring is in progress. Signed-off-by: Stanislaw Gruszka Signed-off-by: John W. Linville --- net/mac80211/ieee80211_i.h | 1 + net/mac80211/mlme.c | 35 +++++++++++++++++++++++------------ net/mac80211/scan.c | 29 ++++++++++++++++++++++++++++- net/mac80211/work.c | 7 +------ 4 files changed, 53 insertions(+), 19 deletions(-) diff --git a/net/mac80211/ieee80211_i.h b/net/mac80211/ieee80211_i.h index 4be11ea3dfc4..1fd8cb26b3ff 100644 --- a/net/mac80211/ieee80211_i.h +++ b/net/mac80211/ieee80211_i.h @@ -1260,6 +1260,7 @@ int ieee80211_request_internal_scan(struct ieee80211_sub_if_data *sdata, int ieee80211_request_scan(struct ieee80211_sub_if_data *sdata, struct cfg80211_scan_request *req); void ieee80211_scan_cancel(struct ieee80211_local *local); +void ieee80211_run_deferred_scan(struct ieee80211_local *local); ieee80211_rx_result ieee80211_scan_rx(struct ieee80211_sub_if_data *sdata, struct sk_buff *skb); diff --git a/net/mac80211/mlme.c b/net/mac80211/mlme.c index bbf1100d90d6..c8836fa7d627 100644 --- a/net/mac80211/mlme.c +++ b/net/mac80211/mlme.c @@ -1447,19 +1447,24 @@ void ieee80211_sta_rx_notify(struct ieee80211_sub_if_data *sdata, static void ieee80211_reset_ap_probe(struct ieee80211_sub_if_data *sdata) { struct ieee80211_if_managed *ifmgd = &sdata->u.mgd; + struct ieee80211_local *local = sdata->local; + mutex_lock(&local->mtx); if (!(ifmgd->flags & (IEEE80211_STA_BEACON_POLL | - IEEE80211_STA_CONNECTION_POLL))) - return; + IEEE80211_STA_CONNECTION_POLL))) { + mutex_unlock(&local->mtx); + return; + } ifmgd->flags &= ~(IEEE80211_STA_CONNECTION_POLL | IEEE80211_STA_BEACON_POLL); - mutex_lock(&sdata->local->iflist_mtx); - ieee80211_recalc_ps(sdata->local, -1); - mutex_unlock(&sdata->local->iflist_mtx); + + mutex_lock(&local->iflist_mtx); + ieee80211_recalc_ps(local, -1); + mutex_unlock(&local->iflist_mtx); if (sdata->local->hw.flags & IEEE80211_HW_CONNECTION_MONITOR) - return; + goto out; /* * We've received a probe response, but are not sure whether @@ -1471,6 +1476,9 @@ static void ieee80211_reset_ap_probe(struct ieee80211_sub_if_data *sdata) mod_timer(&ifmgd->conn_mon_timer, round_jiffies_up(jiffies + IEEE80211_CONNECTION_IDLE_TIME)); +out: + ieee80211_run_deferred_scan(local); + mutex_unlock(&local->mtx); } void ieee80211_sta_tx_notify(struct ieee80211_sub_if_data *sdata, @@ -1546,17 +1554,18 @@ static void ieee80211_mgd_probe_ap(struct ieee80211_sub_if_data *sdata, if (!ieee80211_sdata_running(sdata)) return; - if (sdata->local->scanning) - return; - - if (sdata->local->tmp_channel) - return; - mutex_lock(&ifmgd->mtx); if (!ifmgd->associated) goto out; + mutex_lock(&sdata->local->mtx); + + if (sdata->local->tmp_channel || sdata->local->scanning) { + mutex_unlock(&sdata->local->mtx); + goto out; + } + #ifdef CONFIG_MAC80211_VERBOSE_DEBUG if (beacon && net_ratelimit()) printk(KERN_DEBUG "%s: detected beacon loss from AP " @@ -1583,6 +1592,8 @@ static void ieee80211_mgd_probe_ap(struct ieee80211_sub_if_data *sdata, else ifmgd->flags |= IEEE80211_STA_CONNECTION_POLL; + mutex_unlock(&sdata->local->mtx); + if (already) goto out; diff --git a/net/mac80211/scan.c b/net/mac80211/scan.c index c70e17677135..56175933c28f 100644 --- a/net/mac80211/scan.c +++ b/net/mac80211/scan.c @@ -387,6 +387,33 @@ static int ieee80211_start_sw_scan(struct ieee80211_local *local) return 0; } +static bool ieee80211_can_scan(struct ieee80211_local *local, + struct ieee80211_sub_if_data *sdata) +{ + if (!list_empty(&local->work_list)) + return false; + + if (sdata->vif.type == NL80211_IFTYPE_STATION && + sdata->u.mgd.flags & (IEEE80211_STA_BEACON_POLL | + IEEE80211_STA_CONNECTION_POLL)) + return false; + + return true; +} + +void ieee80211_run_deferred_scan(struct ieee80211_local *local) +{ + lockdep_assert_held(&local->mtx); + + if (!local->scan_req || local->scanning) + return; + + if (!ieee80211_can_scan(local, local->scan_sdata)) + return; + + ieee80211_queue_delayed_work(&local->hw, &local->scan_work, + round_jiffies_relative(0)); +} static int __ieee80211_start_scan(struct ieee80211_sub_if_data *sdata, struct cfg80211_scan_request *req) @@ -399,7 +426,7 @@ static int __ieee80211_start_scan(struct ieee80211_sub_if_data *sdata, if (local->scan_req) return -EBUSY; - if (!list_empty(&local->work_list)) { + if (!ieee80211_can_scan(local, sdata)) { /* wait for the work to finish/time out */ local->scan_req = req; local->scan_sdata = sdata; diff --git a/net/mac80211/work.c b/net/mac80211/work.c index c6e230efa049..1f74af33901b 100644 --- a/net/mac80211/work.c +++ b/net/mac80211/work.c @@ -226,13 +226,8 @@ static void ieee80211_work_work(struct work_struct *work) run_again(local, jiffies + HZ/2); } - if (list_empty(&local->work_list) && local->scan_req && - !local->scanning) - ieee80211_queue_delayed_work(&local->hw, - &local->scan_work, - round_jiffies_relative(0)); - ieee80211_recalc_idle(local); + ieee80211_run_deferred_scan(local); mutex_unlock(&local->mtx); -- 2.20.1