mac80211: allow interface settings changes only when down

We currently allow monitor flags changes and mesh ID changes when
the interface is up, which can lead to trouble. Change it to only
allow when down.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

diff --git a/net/mac80211/cfg.c b/net/mac80211/cfg.c
index a8501f14b1676a130732ddf8534a2a79769875d7..89a183c2327ad0938fa6d30f346bceef5ac2152f 100644 (file)
--- a/net/mac80211/cfg.c
+++ b/net/mac80211/cfg.c
@@ -100,6 +100,9 @@ static int ieee80211_change_iface(struct wiphy *wiphy, int ifindex,
        if (ret)
                return ret;
 
+       if (netif_running(sdata->dev))
+               return -EBUSY;
+
        if (ieee80211_vif_is_mesh(&sdata->vif) && params->mesh_id_len)
                ieee80211_sdata_set_mesh_id(sdata,
                                            params->mesh_id_len,