mac80211: fix double-start of remain-on-channel

When a remain-on-channel item is deleted, we remove it
from the list and then start the next item. However,
if it wasn't actually the first item then calling
ieee80211_start_next_roc() is wrong as it will start
the first item -- even if that was already started.

Fix the two places that do this and add a warning to
prevent the problem from reoccurring.

Reported-by: Eliad Peller <eliad@wizery.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

1 files changed, 2 insertions, 1 deletions

diff --git a/net/mac80211/cfg.c b/net/mac80211/cfg.c
index a6abcd473434..03aff23c70fd 100644
--- a/net/mac80211/cfg.c
+++ b/net/mac80211/cfg.c
@@ -2362,7 +2362,8 @@ static int ieee80211_cancel_roc(struct ieee80211_local *local,
 
                 list_del(&found->list);
 
-                ieee80211_start_next_roc(local);
+                if (found->started)
+                        ieee80211_start_next_roc(local);
                 mutex_unlock(&local->mtx);
 
                 ieee80211_roc_notify_destroy(found);