iwlwifi: pcie: fix unused txq NULL pointer dereference

Before TVQM, all TX queues were allocated straight at init.
With TVQM, queues are allocated on demand and hence we need
to check if a queue exists before dereferencing it.

Fixes: 66128fa08806 ("iwlwifi: move to TVQM mode")
Signed-off-by: Mordechai Goodstein <mordechay.goodstein@intel.com>
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>

1 files changed, 3 insertions, 0 deletions

diff --git a/drivers/net/wireless/intel/iwlwifi/pcie/tx.c b/drivers/net/wireless/intel/iwlwifi/pcie/tx.c
index de50418adae5..034bdb4a0b06 100644
--- a/drivers/net/wireless/intel/iwlwifi/pcie/tx.c
+++ b/drivers/net/wireless/intel/iwlwifi/pcie/tx.c
@@ -298,6 +298,9 @@ void iwl_pcie_txq_check_wrptrs(struct iwl_trans *trans)
         for (i = 0; i < trans->cfg->base_params->num_of_queues; i++) {
                 struct iwl_txq *txq = trans_pcie->txq[i];
 
+                if (!test_bit(i, trans_pcie->queue_used))
+                        continue;
+
                 spin_lock_bh(&txq->lock);
                 if (txq->need_update) {
                         iwl_pcie_txq_inc_wr_ptr(trans, txq);