nl80211: Stop scheduled scan if netlink client disappears

An attribute NL80211_ATTR_SOCKET_OWNER can be set by the scan initiator.
If present, the attribute will cause the scan to be stopped if the client
dies.

Signed-off-by: Jukka Rissanen <jukka.rissanen@linux.intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

diff --git a/include/net/cfg80211.h b/include/net/cfg80211.h
index 45d4d72..bd672ea 100644 (file)
--- a/include/net/cfg80211.h
+++ b/include/net/cfg80211.h
@@ -1517,6 +1517,8 @@ struct cfg80211_match_set {
  *     are 0 in the mask should be randomised, bits that are 1 should
  *     be taken from the @mac_addr
  * @rcu_head: RCU callback used to free the struct
+ * @owner_nlportid: netlink portid of owner (if this should is a request
+ *     owned by a particular socket)
  */
 struct cfg80211_sched_scan_request {
        struct cfg80211_ssid *ssids;
@@ -1539,6 +1541,7 @@ struct cfg80211_sched_scan_request {
        struct net_device *dev;
        unsigned long scan_start;
        struct rcu_head rcu_head;
+       u32 owner_nlportid;
 
        /* keep last */
        struct ieee80211_channel *channels[0];

diff --git a/include/uapi/linux/nl80211.h b/include/uapi/linux/nl80211.h
index b3ada0b..c0383e9 100644 (file)
--- a/include/uapi/linux/nl80211.h
+++ b/include/uapi/linux/nl80211.h
@@ -1672,6 +1672,9 @@ enum nl80211_commands {
  * @NL80211_ATTR_SOCKET_OWNER: Flag attribute, if set during interface
  *     creation then the new interface will be owned by the netlink socket
  *     that created it and will be destroyed when the socket is closed.
+ *     If set during scheduled scan start then the new scan req will be
+ *     owned by the netlink socket that created it and the scheduled scan will
+ *     be stopped when the socket is closed.
  *
  * @NL80211_ATTR_TDLS_INITIATOR: flag attribute indicating the current end is
  *     the TDLS link initiator.

diff --git a/net/wireless/core.c b/net/wireless/core.c
index 0743449..456e4c3 100644 (file)
--- a/net/wireless/core.c
+++ b/net/wireless/core.c
@@ -321,6 +321,20 @@ static void cfg80211_destroy_iface_wk(struct work_struct *work)
        rtnl_unlock();
 }
 
+static void cfg80211_sched_scan_stop_wk(struct work_struct *work)
+{
+       struct cfg80211_registered_device *rdev;
+
+       rdev = container_of(work, struct cfg80211_registered_device,
+                          sched_scan_stop_wk);
+
+       rtnl_lock();
+
+       __cfg80211_stop_sched_scan(rdev, false);
+
+       rtnl_unlock();
+}
+
 /* exported functions */
 
 struct wiphy *wiphy_new_nm(const struct cfg80211_ops *ops, int sizeof_priv,
@@ -407,6 +421,7 @@ use_default_name:
        INIT_LIST_HEAD(&rdev->destroy_list);
        spin_lock_init(&rdev->destroy_list_lock);
        INIT_WORK(&rdev->destroy_work, cfg80211_destroy_iface_wk);
+       INIT_WORK(&rdev->sched_scan_stop_wk, cfg80211_sched_scan_stop_wk);
 
 #ifdef CONFIG_CFG80211_DEFAULT_PS
        rdev->wiphy.flags |= WIPHY_FLAG_PS_ON_BY_DEFAULT;
@@ -787,6 +802,7 @@ void wiphy_unregister(struct wiphy *wiphy)
        flush_work(&rdev->event_work);
        cancel_delayed_work_sync(&rdev->dfs_update_channels_wk);
        flush_work(&rdev->destroy_work);
+       flush_work(&rdev->sched_scan_stop_wk);
 
 #ifdef CONFIG_PM
        if (rdev->wiphy.wowlan_config && rdev->ops->set_wakeup)

diff --git a/net/wireless/core.h b/net/wireless/core.h
index e82030c..801cd49 100644 (file)
--- a/net/wireless/core.h
+++ b/net/wireless/core.h
@@ -91,6 +91,8 @@ struct cfg80211_registered_device {
        struct list_head destroy_list;
        struct work_struct destroy_work;
 
+       struct work_struct sched_scan_stop_wk;
+
        /* must be last because of the way we do wiphy_priv(),
         * and it should at least be aligned to NETDEV_ALIGN */
        struct wiphy wiphy __aligned(NETDEV_ALIGN);

diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c
index bacdf22..7029201 100644 (file)
--- a/net/wireless/nl80211.c
+++ b/net/wireless/nl80211.c
@@ -6214,6 +6214,9 @@ static int nl80211_start_sched_scan(struct sk_buff *skb,
        sched_scan_req->dev = dev;
        sched_scan_req->wiphy = &rdev->wiphy;
 
+       if (info->attrs[NL80211_ATTR_SOCKET_OWNER])
+               sched_scan_req->owner_nlportid = info->snd_portid;
+
        rcu_assign_pointer(rdev->sched_scan_req, sched_scan_req);
 
        nl80211_send_sched_scan(rdev, dev,
@@ -12618,6 +12621,13 @@ static int nl80211_netlink_notify(struct notifier_block * nb,
 
        list_for_each_entry_rcu(rdev, &cfg80211_rdev_list, list) {
                bool schedule_destroy_work = false;
+               bool schedule_scan_stop = false;
+               struct cfg80211_sched_scan_request *sched_scan_req =
+                       rcu_dereference(rdev->sched_scan_req);
+
+               if (sched_scan_req && notify->portid &&
+                   sched_scan_req->owner_nlportid == notify->portid)
+                       schedule_scan_stop = true;
 
                list_for_each_entry_rcu(wdev, &rdev->wdev_list, list) {
                        cfg80211_mlme_unregister_socket(wdev, notify->portid);
@@ -12648,6 +12658,12 @@ static int nl80211_netlink_notify(struct notifier_block * nb,
                                spin_unlock(&rdev->destroy_list_lock);
                                schedule_work(&rdev->destroy_work);
                        }
+               } else if (schedule_scan_stop) {
+                       sched_scan_req->owner_nlportid = 0;
+
+                       if (rdev->ops->sched_scan_stop &&
+                           rdev->wiphy.flags & WIPHY_FLAG_SUPPORTS_SCHED_SCAN)
+                               schedule_work(&rdev->sched_scan_stop_wk);
                }
        }