[PATCH v3 2/6] net/nfb: fix bad pointer access in queue stats

[spinler at cesnet.cz]

From: Martin Spinler <spinler at cesnet.cz>

The driver code has dereferenced the dev->data->rx_queues pointer
without checking for its validity.
Pointer invalidation can occur when the eth_dev_rx_queue_config
is called with set to 0, for example.

Moreover, an array of pointers (to a structure) was used like array
of structures (which worked with early dereference just for one queue).

Fixes: 6435f9a0ac22 ("net/nfb: add new netcope driver")
Cc: stable at dpdk.org

Signed-off-by: Martin Spinler <spinler at cesnet.cz>
---
 drivers/net/nfb/nfb_stats.c | 46 ++++++++++++++++++-------------------
 1 file changed, 23 insertions(+), 23 deletions(-)

diff --git a/drivers/net/nfb/nfb_stats.c b/drivers/net/nfb/nfb_stats.c
index 4ea6b7be21..27a01c3160 100644
--- a/drivers/net/nfb/nfb_stats.c
+++ b/drivers/net/nfb/nfb_stats.c
@@ -20,28 +20,28 @@ nfb_eth_stats_get(struct rte_eth_dev *dev, struct rte_eth_stats *stats,
 	uint64_t rx_total_bytes = 0;
 	uint64_t tx_total_bytes = 0;
 
-	struct ndp_rx_queue *rx_queue = *((struct ndp_rx_queue **)
-		dev->data->rx_queues);
-	struct ndp_tx_queue *tx_queue = *((struct ndp_tx_queue **)
-		dev->data->tx_queues);
+	struct ndp_rx_queue *rx_queue;
+	struct ndp_tx_queue *tx_queue;
 
 	for (i = 0; i < nb_rx; i++) {
+		rx_queue = dev->data->rx_queues[i];
 		if (qstats && i < RTE_ETHDEV_QUEUE_STAT_CNTRS) {
-			qstats->q_ipackets[i] = rx_queue[i].rx_pkts;
-			qstats->q_ibytes[i] = rx_queue[i].rx_bytes;
+			qstats->q_ipackets[i] = rx_queue->rx_pkts;
+			qstats->q_ibytes[i] = rx_queue->rx_bytes;
 		}
-		rx_total += rx_queue[i].rx_pkts;
-		rx_total_bytes += rx_queue[i].rx_bytes;
+		rx_total += rx_queue->rx_pkts;
+		rx_total_bytes += rx_queue->rx_bytes;
 	}
 
 	for (i = 0; i < nb_tx; i++) {
+		tx_queue = dev->data->tx_queues[i];
 		if (qstats && i < RTE_ETHDEV_QUEUE_STAT_CNTRS) {
-			qstats->q_opackets[i] = tx_queue[i].tx_pkts;
-			qstats->q_obytes[i] = tx_queue[i].tx_bytes;
+			qstats->q_opackets[i] = tx_queue->tx_pkts;
+			qstats->q_obytes[i] = tx_queue->tx_bytes;
 		}
-		tx_total += tx_queue[i].tx_pkts;
-		tx_total_bytes += tx_queue[i].tx_bytes;
-		tx_err_total += tx_queue[i].err_pkts;
+		tx_total += tx_queue->tx_pkts;
+		tx_total_bytes += tx_queue->tx_bytes;
+		tx_err_total += tx_queue->err_pkts;
 	}
 
 	stats->ipackets = rx_total;
@@ -59,20 +59,20 @@ nfb_eth_stats_reset(struct rte_eth_dev *dev)
 	uint16_t nb_rx = dev->data->nb_rx_queues;
 	uint16_t nb_tx = dev->data->nb_tx_queues;
 
-	struct ndp_rx_queue *rx_queue = *((struct ndp_rx_queue **)
-		dev->data->rx_queues);
-	struct ndp_tx_queue *tx_queue = *((struct ndp_tx_queue **)
-		dev->data->tx_queues);
+	struct ndp_rx_queue *rx_queue;
+	struct ndp_tx_queue *tx_queue;
 
 	for (i = 0; i < nb_rx; i++) {
-		rx_queue[i].rx_pkts = 0;
-		rx_queue[i].rx_bytes = 0;
-		rx_queue[i].err_pkts = 0;
+		rx_queue = dev->data->rx_queues[i];
+		rx_queue->rx_pkts = 0;
+		rx_queue->rx_bytes = 0;
+		rx_queue->err_pkts = 0;
 	}
 	for (i = 0; i < nb_tx; i++) {
-		tx_queue[i].tx_pkts = 0;
-		tx_queue[i].tx_bytes = 0;
-		tx_queue[i].err_pkts = 0;
+		tx_queue = dev->data->tx_queues[i];
+		tx_queue->tx_pkts = 0;
+		tx_queue->tx_bytes = 0;
+		tx_queue->err_pkts = 0;
 	}
 
 	return 0;
-- 
2.52.0