cfg80211: Fix radar event during another phy CAC

[ Upstream commit 26ec17a1dc5ecdd8d91aba63ead6f8b5ad5dea0d ]

In case a radar event of CAC_FINISHED or RADAR_DETECTED
happens during another phy is during CAC we might need
to cancel that CAC.

If we got a radar in a channel that another phy is now
doing CAC on then the CAC should be canceled there.

If, for example, 2 phys doing CAC on the same channels,
or on comptable channels, once on of them will finish his
CAC the other might need to cancel his CAC, since it is no
longer relevant.

To fix that the commit adds an callback and implement it in
mac80211 to end CAC.
This commit also adds a call to said callback if after a radar
event we see the CAC is no longer relevant

Signed-off-by: Orr Mazor <Orr.Mazor@tandemg.com>
Reviewed-by: Sergey Matyukevich <sergey.matyukevich.os@quantenna.com>
Link: https://lore.kernel.org/r/20191222145449.15792-1-Orr.Mazor@tandemg.com
[slightly reformat/reword commit message]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/include/net/cfg80211.h b/include/net/cfg80211.h
index 1fa2e72ff7a6ae2c8402491f641f169745ea639c..ae936cd5567e0bcf124e13f7fa75c7e1c4201f4c 100644 (file)
--- a/include/net/cfg80211.h
+++ b/include/net/cfg80211.h
@@ -3050,6 +3050,9 @@ struct cfg80211_external_auth_params {
  *
  * @start_radar_detection: Start radar detection in the driver.
  *
+ * @end_cac: End running CAC, probably because a related CAC
+ *     was finished on another phy.
+ *
  * @update_ft_ies: Provide updated Fast BSS Transition information to the
  *     driver. If the SME is in the driver/firmware, this information can be
  *     used in building Authentication and Reassociation Request frames.
@@ -3364,6 +3367,8 @@ struct cfg80211_ops {
                                         struct net_device *dev,
                                         struct cfg80211_chan_def *chandef,
                                         u32 cac_time_ms);
+       void    (*end_cac)(struct wiphy *wiphy,
+                               struct net_device *dev);
        int     (*update_ft_ies)(struct wiphy *wiphy, struct net_device *dev,
                                 struct cfg80211_update_ft_ies_params *ftie);
        int     (*crit_proto_start)(struct wiphy *wiphy,

diff --git a/net/mac80211/cfg.c b/net/mac80211/cfg.c
index e46944500cfa1cadb0e1319616c4d89560aa9f74..cb7076d9a76986456b805519216c3d112227c285 100644 (file)
--- a/net/mac80211/cfg.c
+++ b/net/mac80211/cfg.c
@@ -2825,6 +2825,28 @@ static int ieee80211_start_radar_detection(struct wiphy *wiphy,
        return err;
 }
 
+static void ieee80211_end_cac(struct wiphy *wiphy,
+                             struct net_device *dev)
+{
+       struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
+       struct ieee80211_local *local = sdata->local;
+
+       mutex_lock(&local->mtx);
+       list_for_each_entry(sdata, &local->interfaces, list) {
+               /* it might be waiting for the local->mtx, but then
+                * by the time it gets it, sdata->wdev.cac_started
+                * will no longer be true
+                */
+               cancel_delayed_work(&sdata->dfs_cac_timer_work);
+
+               if (sdata->wdev.cac_started) {
+                       ieee80211_vif_release_channel(sdata);
+                       sdata->wdev.cac_started = false;
+               }
+       }
+       mutex_unlock(&local->mtx);
+}
+
 static struct cfg80211_beacon_data *
 cfg80211_beacon_dup(struct cfg80211_beacon_data *beacon)
 {
@@ -3848,6 +3870,7 @@ const struct cfg80211_ops mac80211_config_ops = {
 #endif
        .get_channel = ieee80211_cfg_get_channel,
        .start_radar_detection = ieee80211_start_radar_detection,
+       .end_cac = ieee80211_end_cac,
        .channel_switch = ieee80211_channel_switch,
        .set_qos_map = ieee80211_set_qos_map,
        .set_ap_chanwidth = ieee80211_set_ap_chanwidth,

diff --git a/net/wireless/rdev-ops.h b/net/wireless/rdev-ops.h
index 4cff76f33d45f6047f785b258f3fb75e5288ba88..a8c58aeb9dde9404cdbd86858baa65955879d1e3 100644 (file)
--- a/net/wireless/rdev-ops.h
+++ b/net/wireless/rdev-ops.h
@@ -1170,6 +1170,16 @@ rdev_start_radar_detection(struct cfg80211_registered_device *rdev,
        return ret;
 }
 
+static inline void
+rdev_end_cac(struct cfg80211_registered_device *rdev,
+            struct net_device *dev)
+{
+       trace_rdev_end_cac(&rdev->wiphy, dev);
+       if (rdev->ops->end_cac)
+               rdev->ops->end_cac(&rdev->wiphy, dev);
+       trace_rdev_return_void(&rdev->wiphy);
+}
+
 static inline int
 rdev_set_mcast_rate(struct cfg80211_registered_device *rdev,
                    struct net_device *dev,

diff --git a/net/wireless/reg.c b/net/wireless/reg.c
index 4c3c8a1c116da32635cb354694ebc0ffb3027b0c..018c60be153a763cbebecd601df51057aee7d17c 100644 (file)
--- a/net/wireless/reg.c
+++ b/net/wireless/reg.c
@@ -3840,6 +3840,25 @@ bool regulatory_pre_cac_allowed(struct wiphy *wiphy)
        return pre_cac_allowed;
 }
 
+static void cfg80211_check_and_end_cac(struct cfg80211_registered_device *rdev)
+{
+       struct wireless_dev *wdev;
+       /* If we finished CAC or received radar, we should end any
+        * CAC running on the same channels.
+        * the check !cfg80211_chandef_dfs_usable contain 2 options:
+        * either all channels are available - those the CAC_FINISHED
+        * event has effected another wdev state, or there is a channel
+        * in unavailable state in wdev chandef - those the RADAR_DETECTED
+        * event has effected another wdev state.
+        * In both cases we should end the CAC on the wdev.
+        */
+       list_for_each_entry(wdev, &rdev->wiphy.wdev_list, list) {
+               if (wdev->cac_started &&
+                   !cfg80211_chandef_dfs_usable(&rdev->wiphy, &wdev->chandef))
+                       rdev_end_cac(rdev, wdev->netdev);
+       }
+}
+
 void regulatory_propagate_dfs_state(struct wiphy *wiphy,
                                    struct cfg80211_chan_def *chandef,
                                    enum nl80211_dfs_state dfs_state,
@@ -3866,8 +3885,10 @@ void regulatory_propagate_dfs_state(struct wiphy *wiphy,
                cfg80211_set_dfs_state(&rdev->wiphy, chandef, dfs_state);
 
                if (event == NL80211_RADAR_DETECTED ||
-                   event == NL80211_RADAR_CAC_FINISHED)
+                   event == NL80211_RADAR_CAC_FINISHED) {
                        cfg80211_sched_dfs_chan_update(rdev);
+                       cfg80211_check_and_end_cac(rdev);
+               }
 
                nl80211_radar_notify(rdev, chandef, event, NULL, GFP_KERNEL);
        }

diff --git a/net/wireless/trace.h b/net/wireless/trace.h
index 7c73510b161f3b84ce3d7d24dd3b9aa3b472823e..54b0bb344cf93811c96b36ddd21709b889741123 100644 (file)
--- a/net/wireless/trace.h
+++ b/net/wireless/trace.h
@@ -607,6 +607,11 @@ DEFINE_EVENT(wiphy_netdev_evt, rdev_flush_pmksa,
        TP_ARGS(wiphy, netdev)
 );
 
+DEFINE_EVENT(wiphy_netdev_evt, rdev_end_cac,
+            TP_PROTO(struct wiphy *wiphy, struct net_device *netdev),
+            TP_ARGS(wiphy, netdev)
+);
+
 DECLARE_EVENT_CLASS(station_add_change,
        TP_PROTO(struct wiphy *wiphy, struct net_device *netdev, u8 *mac,
                 struct station_parameters *params),