commit: d72308bff5c2fa207949a5925b020bce74495e33 From: Stanislaw Gruszka <[email protected]> Date: Mon, 19 Mar 2012 16:00:26 +0100 Subject: mac80211: fix possible tid_rx->reorder_timer use after free
Is possible that we will arm the tid_rx->reorder_timer after del_timer_sync() in ___ieee80211_stop_rx_ba_session(). We need to stop timer after RCU grace period finish, so move it to ieee80211_free_tid_rx(). Timer will not be armed again, as rcu_dereference(sta->ampdu_mlme.tid_rx[tid]) will return NULL. Debug object detected problem with the following warning: ODEBUG: free active (active state 0) object type: timer_list hint: sta_rx_agg_reorder_timer_expired+0x0/0xf0 [mac80211] Bug report (with all warning messages): https://bugzilla.redhat.com/show_bug.cgi?id=804007 Reported-by: "jan p. springer" <[email protected]> Cc: [email protected] Signed-off-by: Stanislaw Gruszka <[email protected]> Signed-off-by: John W. Linville <[email protected]> --- net/mac80211/agg-rx.c | 3 ++- 1 files changed, 2 insertions(+), 1 deletions(-) diff --git a/net/mac80211/agg-rx.c b/net/mac80211/agg-rx.c index 1068f66..64d3ce5 100644 --- a/net/mac80211/agg-rx.c +++ b/net/mac80211/agg-rx.c @@ -49,6 +49,8 @@ static void ieee80211_free_tid_rx(struct rcu_head *h) container_of(h, struct tid_ampdu_rx, rcu_head); int i; + del_timer_sync(&tid_rx->reorder_timer); + for (i = 0; i < tid_rx->buf_size; i++) dev_kfree_skb(tid_rx->reorder_buf[i]); kfree(tid_rx->reorder_buf); @@ -91,7 +93,6 @@ void ___ieee80211_stop_rx_ba_session(struct sta_info *sta, u16 tid, tid, WLAN_BACK_RECIPIENT, reason); del_timer_sync(&tid_rx->session_timer); - del_timer_sync(&tid_rx->reorder_timer); call_rcu(&tid_rx->rcu_head, ieee80211_free_tid_rx); } -- 1.7.3.4 -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
