[PATCH] Staging: net/ethernet/broadcom: Add error pointer check in bcmsysport.c

[Dipendra Khadka <kdipendra88@gmail.com>]

Smatch reported following:
'''
drivers/net/ethernet/broadcom/bcmsysport.c:2343 bcm_sysport_map_queues() error: 'dp' dereferencing possible ERR_PTR()
drivers/net/ethernet/broadcom/bcmsysport.c:2395 bcm_sysport_unmap_queues() error: 'dp' dereferencing possible ERR_PTR()
'''

Adding error pointer check before dereferencing 'dp'.

Signed-off-by: Dipendra Khadka <kdipendra88@gmail.com>
---
 drivers/net/ethernet/broadcom/bcmsysport.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/drivers/net/ethernet/broadcom/bcmsysport.c b/drivers/net/ethernet/broadcom/bcmsysport.c
index c9faa8540859..b849c11e2bb6 100644
--- a/drivers/net/ethernet/broadcom/bcmsysport.c
+++ b/drivers/net/ethernet/broadcom/bcmsysport.c
@@ -2337,6 +2337,9 @@ static int bcm_sysport_map_queues(struct net_device *dev,
 	unsigned int num_tx_queues;
 	unsigned int q, qp, port;
 
+	if (IS_ERR(dp))
+		return PTR_ERR(dp);
+
 	/* We can't be setting up queue inspection for non directly attached
 	 * switches
 	 */
@@ -2392,6 +2395,9 @@ static int bcm_sysport_unmap_queues(struct net_device *dev,
 	unsigned int num_tx_queues;
 	unsigned int q, qp, port;
 
+	if (IS_ERR(dp))
+		return PTR_ERR(dp);
+
 	port = dp->index;
 
 	num_tx_queues = slave_dev->real_num_tx_queues;
-- 
2.43.0