From e562078a19226660299eeaf40a50752672214f11 Mon Sep 17 00:00:00 2001 From: Ben Greear Date: Wed, 12 Jun 2013 14:08:44 -0700 Subject: [PATCH] mac80211: Ensure tid_start_tx is protected by sta->lock All accesses of the tid_start_tx lock should be protected by sta->lock if there is any chance that another thread could still be accessing the sta object. Signed-off-by: Ben Greear Signed-off-by: Johannes Berg --- net/mac80211/ht.c | 4 +++- net/mac80211/sta_info.h | 1 + 2 files changed, 4 insertions(+), 1 deletion(-) diff --git a/net/mac80211/ht.c b/net/mac80211/ht.c index 75dff338f581..f83534f6a2ee 100644 --- a/net/mac80211/ht.c +++ b/net/mac80211/ht.c @@ -281,13 +281,14 @@ void ieee80211_ba_session_work(struct work_struct *work) sta, tid, WLAN_BACK_RECIPIENT, WLAN_REASON_UNSPECIFIED, true); + spin_lock_bh(&sta->lock); + tid_tx = sta->ampdu_mlme.tid_start_tx[tid]; if (tid_tx) { /* * Assign it over to the normal tid_tx array * where it "goes live". */ - spin_lock_bh(&sta->lock); sta->ampdu_mlme.tid_start_tx[tid] = NULL; /* could there be a race? */ @@ -300,6 +301,7 @@ void ieee80211_ba_session_work(struct work_struct *work) ieee80211_tx_ba_session_handle_start(sta, tid); continue; } + spin_unlock_bh(&sta->lock); tid_tx = rcu_dereference_protected_tid_tx(sta, tid); if (tid_tx && test_and_clear_bit(HT_AGG_STATE_WANT_STOP, diff --git a/net/mac80211/sta_info.h b/net/mac80211/sta_info.h index bd12fc54266c..4208dbd5861f 100644 --- a/net/mac80211/sta_info.h +++ b/net/mac80211/sta_info.h @@ -203,6 +203,7 @@ struct tid_ampdu_rx { * driver requested to close until the work for it runs * @mtx: mutex to protect all TX data (except non-NULL assignments * to tid_tx[idx], which are protected by the sta spinlock) + * tid_start_tx is also protected by sta->lock. */ struct sta_ampdu_mlme { struct mutex mtx; -- 2.20.1