mac80211: handle failed scan requests in STA mode

If cfg80211 requests a scan it awaits either a return code != 0 from
the scan function or the cfg80211_scan_done to be called. In case of
a STA mac80211's scan function ever returns 0 and queues the scan request.
If ieee80211_sta_work is executed and ieee80211_start_scan fails for
some reason cfg80211_scan_done will never be called but cfg80211 still
thinks the scan was triggered successfully and will refuse any future
scan requests due to drv->scan_req not being cleaned up.

If a scan is triggered from within the MLME a similar problem appears. If
ieee80211_start_scan returns an error, local->scan_req will not be reset
and mac80211 will refuse any future scan requests.

Hence, in both cases call ieee80211_scan_failed (which notifies cfg80211
and resets local->scan_req) if ieee80211_start_scan returns an error.

Signed-off-by: Helmut Schaa <helmut.schaa@googlemail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 1 insertions, 0 deletions

diff --git a/net/mac80211/ieee80211_i.h b/net/mac80211/ieee80211_i.h
index ecbc8e0cb3e7..fbb91f1aebb2 100644
--- a/net/mac80211/ieee80211_i.h
+++ b/net/mac80211/ieee80211_i.h
@@ -972,6 +972,7 @@ int ieee80211_sta_set_extra_ie(struct ieee80211_sub_if_data *sdata,
                                char *ie, size_t len);
 
 void ieee80211_mlme_notify_scan_completed(struct ieee80211_local *local);
+void ieee80211_scan_failed(struct ieee80211_local *local);
 int ieee80211_start_scan(struct ieee80211_sub_if_data *scan_sdata,
                          struct cfg80211_scan_request *req);
 struct ieee80211_bss *