net/bnxt: check VF representor pointer before access

[ upstream commit f306225 ]

The PF or trusted VF Rx handler could invoke the VF representor's
Rx function without knowledge of the application cleaning up the
representor ports. Check if the vfr_bp pointer is valid before
accessing it.

Fixes: 6dc8323 ("net/bnxt: support port representor data path")

Signed-off-by: Ajit Khaparde <ajit.khaparde@broadcom.com>
Reviewed-by: Kalesh AP <kalesh-anakkur.purayil@broadcom.com>
Reviewed-by: Somnath Kotur <somnath.kotur@broadcom.com>

drivers/net/bnxt/bnxt_reps.c

@@ -35,16 +35,20 @@ static const struct eth_dev_ops bnxt_rep_dev_ops = {
 uint16_t
 bnxt_vfr_recv(uint16_t port_id, uint16_t queue_id, struct rte_mbuf *mbuf)
 {
-	struct rte_mbuf **prod_rx_buf;
+	struct bnxt_representor *vfr_bp = NULL;
 	struct bnxt_rx_ring_info *rep_rxr;
-	struct bnxt_rx_queue *rep_rxq;
 	struct rte_eth_dev *vfr_eth_dev;
-	struct bnxt_representor *vfr_bp;
+	struct rte_mbuf **prod_rx_buf;
+	struct bnxt_rx_queue *rep_rxq;
 	uint16_t mask;
 	uint8_t que;
 
 	vfr_eth_dev = &rte_eth_devices[port_id];
-	vfr_bp = vfr_eth_dev->data->dev_private;
+	vfr_bp = vfr_eth_dev ? vfr_eth_dev->data->dev_private : NULL;
+
+	if (unlikely(vfr_bp == NULL))
+		return 1;
+
 	/* If rxq_id happens to be > nr_rings, use ring 0 */
 	que = queue_id < vfr_bp->rx_nr_rings ? queue_id : 0;
 	rep_rxq = vfr_bp->rx_queues[que];