mac80211: fix two remote exploits

Lennert Buytenhek noticed a remotely triggerable problem
in mac80211, which is due to some code shuffling I did
that ended up changing the order in which things were
done -- this was in

  commit d75636ef9c
  Author: Johannes Berg <johannes@sipsolutions.net>
  Date:   Tue Feb 10 21:25:53 2009 +0100

    mac80211: RX aggregation: clean up stop session

The problem is that the BUG_ON moved before the various
checks, and as such can be triggered.

As the comment indicates, the BUG_ON can be removed since
the ampdu_action callback must already exist when the
state is OPERATIONAL.

A similar code path leads to a WARN_ON in
ieee80211_stop_tx_ba_session, which can also be removed.

Cc: stable@kernel.org [2.6.29+]
Cc: Lennert Buytenhek <buytenh@marvell.com>
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
This commit is contained in:
Johannes Berg 2009-11-20 09:15:51 +01:00 committed by John W. Linville
parent 3e9848403a
commit 4253119acf
2 changed files with 1 additions and 5 deletions

View file

@ -85,10 +85,6 @@ void ieee80211_sta_stop_rx_ba_session(struct ieee80211_sub_if_data *sdata, u8 *r
struct ieee80211_local *local = sdata->local;
struct sta_info *sta;
/* stop HW Rx aggregation. ampdu_action existence
* already verified in session init so we add the BUG_ON */
BUG_ON(!local->ops->ampdu_action);
rcu_read_lock();
sta = sta_info_get(local, ra);

View file

@ -545,7 +545,7 @@ int ieee80211_stop_tx_ba_session(struct ieee80211_hw *hw,
struct sta_info *sta;
int ret = 0;
if (WARN_ON(!local->ops->ampdu_action))
if (!local->ops->ampdu_action)
return -EINVAL;
if (tid >= STA_TID_NUM)