mac80211: reestablish mis-configured existing Rx BA sessions

When forming a Rx BA session, sometimes the ADDBA response gets lost.
This leads to a situation where the session is configured locally, but
doesn't exist on the remote side. Subsequent ADDBA requests are declined
by mac80211.

Fix this by assuming the session state of the initiator is the correct
one. When receiving an unexpected ADDBA request on a TID with an active
Rx BA session, delete the existing one and establish a new session.

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

diff --git a/net/mac80211/agg-rx.c b/net/mac80211/agg-rx.c
index 89b0b2ca6db673978057ae8754e3a6f0af10963b..ebadb9ac9a7eaf674cf283938448baf8381d0294 100644 (file)
--- a/net/mac80211/agg-rx.c
+++ b/net/mac80211/agg-rx.c
@@ -262,7 +262,11 @@ void ieee80211_process_addba_request(struct ieee80211_local *local,
                                "%pM on tid %u\n",
                                mgmt->sa, tid);
 #endif /* CONFIG_MAC80211_HT_DEBUG */
-               goto end;
+
+               /* delete existing Rx BA session on the same tid */
+               ___ieee80211_stop_rx_ba_session(sta, tid, WLAN_BACK_RECIPIENT,
+                                               WLAN_STATUS_UNSPECIFIED_QOS,
+                                               false);
        }
 
        /* prepare A-MPDU MLME for Rx aggregation */