From f89e07d4cf2660a2956bc350a201398dda85284e Mon Sep 17 00:00:00 2001 From: Johannes Berg Date: Wed, 6 Jul 2016 14:44:14 +0200 Subject: [PATCH] mac80211: agg-rx: refuse ADDBA Request with timeout update The current implementation of handling ADDBA Request while a session is already active with the peer is wrong - in case the peer is using the existing session's dialog token this should be treated as update to the session, which can update the timeout value. We don't really have a good way of supporting that, so reject, but implement the required behaviour in the spec of "Even if the updated ADDBA Request frame is not accepted, the original Block ACK setup remains active." (802.11-2012 10.5.4) Signed-off-by: Johannes Berg --- net/mac80211/agg-rx.c | 18 ++++++++++++++++++ 1 file changed, 18 insertions(+) diff --git a/net/mac80211/agg-rx.c b/net/mac80211/agg-rx.c index 3a8f881b22f1..a9aff6079c42 100644 --- a/net/mac80211/agg-rx.c +++ b/net/mac80211/agg-rx.c @@ -306,6 +306,24 @@ void __ieee80211_start_rx_ba_session(struct sta_info *sta, mutex_lock(&sta->ampdu_mlme.mtx); if (test_bit(tid, sta->ampdu_mlme.agg_session_valid)) { + tid_agg_rx = rcu_dereference_protected( + sta->ampdu_mlme.tid_rx[tid], + lockdep_is_held(&sta->ampdu_mlme.mtx)); + + if (tid_agg_rx->dialog_token == dialog_token) { + ht_dbg_ratelimited(sta->sdata, + "updated AddBA Req from %pM on tid %u\n", + sta->sta.addr, tid); + /* We have no API to update the timeout value in the + * driver so reject the timeout update. + */ + status = WLAN_STATUS_REQUEST_DECLINED; + ieee80211_send_addba_resp(sta->sdata, sta->sta.addr, + tid, dialog_token, status, + 1, buf_size, timeout); + goto end; + } + ht_dbg_ratelimited(sta->sdata, "unexpected AddBA Req from %pM on tid %u\n", sta->sta.addr, tid); -- 2.20.1