[PATCH AUTOSEL 4.14 067/371] iwlwifi: mvm: avoid possible access out of array.

Sasha Levin
2020-01-16T18:36:10Z

From: Mordechay Goodstein <mordechay.goodstein@intel.com>

[ Upstream commit b0d795a9ae558209656b18930c2b4def5f8fdfb8 ]

The value in txq_id can be out of array scope,
validate it before accessing the array.

Signed-off-by: Mordechay Goodstein <mordechay.goodstein@intel.com>
Fixes: cf961e16620f ("iwlwifi: mvm: support dqa-mode agg on non-shared queue")
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/net/wireless/intel/iwlwifi/mvm/sta.c | 19 +++++++++++++------
1 file changed, 13 insertions(+), 6 deletions(-)

diff --git a/drivers/net/wireless/intel/iwlwifi/mvm/sta.c b/drivers/net/wireless/intel/iwlwifi/mvm/sta.c
index 0cfdbaa2af3a..684c0f65a052 100644
--- a/drivers/net/wireless/intel/iwlwifi/mvm/sta.c
+++ b/drivers/net/wireless/intel/iwlwifi/mvm/sta.c
@@ -2417,7 +2417,7 @@ int iwl_mvm_sta_tx_agg_start(struct iwl_mvm *mvm, struct ieee80211_vif *vif,
struct iwl_mvm_sta *mvmsta = iwl_mvm_sta_from_mac80211(sta);
struct iwl_mvm_tid_data *tid_data;
u16 normalized_ssn;
- int txq_id;
+ u16 txq_id;
int ret;

if (WARN_ON_ONCE(tid >= IWL_MAX_TID_COUNT))
@@ -2452,17 +2452,24 @@ int iwl_mvm_sta_tx_agg_start(struct iwl_mvm *mvm, struct ieee80211_vif *vif,
*/
txq_id = mvmsta->tid_data[tid].txq_id;
if (txq_id == IWL_MVM_INVALID_QUEUE) {
- txq_id = iwl_mvm_find_free_queue(mvm, mvmsta->sta_id,
- IWL_MVM_DQA_MIN_DATA_QUEUE,
- IWL_MVM_DQA_MAX_DATA_QUEUE);
- if (txq_id < 0) {
- ret = txq_id;
+ ret = iwl_mvm_find_free_queue(mvm, mvmsta->sta_id,
+ IWL_MVM_DQA_MIN_DATA_QUEUE,
+ IWL_MVM_DQA_MAX_DATA_QUEUE);
+ if (ret < 0) {
IWL_ERR(mvm, "Failed to allocate agg queue\n");
goto release_locks;
}

+ txq_id = ret;
+
/* TXQ hasn't yet been enabled, so mark it only as reserved */
mvm->queue_info[txq_id].status = IWL_MVM_QUEUE_RESERVED;
+ } else if (WARN_ON(txq_id >= IWL_MAX_HW_QUEUES)) {
+ ret = -ENXIO;
+ IWL_ERR(mvm, "tid_id %d out of range (0, %d)!\n",
+ tid, IWL_MAX_HW_QUEUES - 1);
+ goto out;
+
} else if (unlikely(mvm->queue_info[txq_id].status ==
IWL_MVM_QUEUE_SHARED)) {
ret = -ENXIO;
--
2.20.1