iwlwifi: dvm: prevent an out of bounds access

commit 0b0f934e92a8eaed2e6c48a50eae6f84661f74f3 upstream.

iwlagn_check_ratid_empty takes the tid as a parameter, but
it doesn't check that it is not IWL_TID_NON_QOS.
Since IWL_TID_NON_QOS = 8 and iwl_priv::tid_data is an array
with 8 entries, accessing iwl_priv::tid_data[IWL_TID_NON_QOS]
is a bad idea.
This happened in iwlagn_rx_reply_tx. Since
iwlagn_check_ratid_empty is relevant only to check whether
we can open A-MPDU, this flow is irrelevant if tid is
IWL_TID_NON_QOS. Call iwlagn_check_ratid_empty only inside
the
	if (tid != IWL_TID_NON_QOS)

a few lines earlier in the function.

Reported-by: Seraphime Kirkovski <kirkseraph@gmail.com>
Tested-by: Seraphime Kirkovski <kirkseraph@gmail.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/net/wireless/intel/iwlwifi/dvm/tx.c b/drivers/net/wireless/intel/iwlwifi/dvm/tx.c
index 4b97371..838946d 100644 (file)
--- a/drivers/net/wireless/intel/iwlwifi/dvm/tx.c
+++ b/drivers/net/wireless/intel/iwlwifi/dvm/tx.c
@@ -1190,11 +1190,11 @@ void iwlagn_rx_reply_tx(struct iwl_priv *priv, struct iwl_rx_cmd_buffer *rxb)
                                next_reclaimed;
                        IWL_DEBUG_TX_REPLY(priv, "Next reclaimed packet:%d\n",
                                                  next_reclaimed);
+                       iwlagn_check_ratid_empty(priv, sta_id, tid);
                }
 
                iwl_trans_reclaim(priv->trans, txq_id, ssn, &skbs);
 
-               iwlagn_check_ratid_empty(priv, sta_id, tid);
                freed = 0;
 
                /* process frames */