Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67;
From:   Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To:     linux-kernel@vger.kernel.org
Cc:     Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        stable@vger.kernel.org,
        Mordechay Goodstein <mordechay.goodstein@intel.com>,
        Luca Coelho <luciano.coelho@intel.com>,
        Sasha Levin <sashal@kernel.org>
Subject: [PATCH 4.19 148/639] iwlwifi: mvm: avoid possible access out of array.
Date:   Fri, 24 Jan 2020 10:25:18 +0100
Message-Id: <20200124093105.760522533@linuxfoundation.org>
In-Reply-To: <20200124093047.008739095@linuxfoundation.org>
References: <20200124093047.008739095@linuxfoundation.org>
User-Agent: quilt/0.66
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

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 e850aa504b608..69057701641e0 100644
--- a/drivers/net/wireless/intel/iwlwifi/mvm/sta.c
+++ b/drivers/net/wireless/intel/iwlwifi/mvm/sta.c
@@ -2462,7 +2462,7 @@ 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))
@@ -2506,17 +2506,24 @@ 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