mac80211: fix tid_agg_rx NULL dereference

On drivers setting the SUPPORTS_REORDERING_BUFFER hardware flag,
we crash when the peer sends an AddBA request while we already
have a session open on the seame TID; this is because on those
drivers, the tid_agg_rx is left NULL even though the session is
valid, and the agg_session_valid bit is set.

To fix this, store the dialog tokens outside the tid_agg_rx to
be able to compare them to the received AddBA request.

Fixes: f89e07d4cf ("mac80211: agg-rx: refuse ADDBA Request with timeout update")
Reported-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
This commit is contained in:
Johannes Berg
2016-10-18 23:12:08 +03:00
parent a1264c3d6c
commit 1c3d185a9a
3 changed files with 5 additions and 9 deletions

View File

@@ -184,7 +184,6 @@ struct tid_ampdu_tx {
* @ssn: Starting Sequence Number expected to be aggregated.
* @buf_size: buffer size for incoming A-MPDUs
* @timeout: reset timer value (in TUs).
* @dialog_token: dialog token for aggregation session
* @rcu_head: RCU head used for freeing this struct
* @reorder_lock: serializes access to reorder buffer, see below.
* @auto_seq: used for offloaded BA sessions to automatically pick head_seq_and
@@ -213,7 +212,6 @@ struct tid_ampdu_rx {
u16 ssn;
u16 buf_size;
u16 timeout;
u8 dialog_token;
bool auto_seq;
bool removed;
};
@@ -225,6 +223,7 @@ struct tid_ampdu_rx {
* to tid_tx[idx], which are protected by the sta spinlock)
* tid_start_tx is also protected by sta->lock.
* @tid_rx: aggregation info for Rx per TID -- RCU protected
* @tid_rx_token: dialog tokens for valid aggregation sessions
* @tid_rx_timer_expired: bitmap indicating on which TIDs the
* RX timer expired until the work for it runs
* @tid_rx_stop_requested: bitmap indicating which BA sessions per TID the
@@ -243,6 +242,7 @@ struct sta_ampdu_mlme {
struct mutex mtx;
/* rx */
struct tid_ampdu_rx __rcu *tid_rx[IEEE80211_NUM_TIDS];
u8 tid_rx_token[IEEE80211_NUM_TIDS];
unsigned long tid_rx_timer_expired[BITS_TO_LONGS(IEEE80211_NUM_TIDS)];
unsigned long tid_rx_stop_requested[BITS_TO_LONGS(IEEE80211_NUM_TIDS)];
unsigned long agg_session_valid[BITS_TO_LONGS(IEEE80211_NUM_TIDS)];