mac80211: fix possible tid_rx->reorder_timer use after free
commit26122d741decf22de810c1f6e7ef614db97ba1ad
authorStanislaw Gruszka <sgruszka@redhat.com>
Mon, 19 Mar 2012 15:00:26 +0000 (19 16:00 +0100)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Fri, 13 Apr 2012 16:13:52 +0000 (13 09:13 -0700)
tree3720378d9bc3617f6a4f59b6f94f75280c64a5cb
parentd89e8755daca2a1e2b1608d0a0dfc3d5990bb50e
mac80211: fix possible tid_rx->reorder_timer use after free

commit d72308bff5c2fa207949a5925b020bce74495e33 upstream.

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" <jsd@igroup.org>
Signed-off-by: Stanislaw Gruszka <sgruszka@redhat.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
net/mac80211/agg-rx.c