[PATCH 09/12] net: hinic: fix null pointer dereference on pointer hwdev

[Ike Panhc]

From: Colin Ian King <colin.king at canonical.com>

BugLink: https://bugs.launchpad.net/bugs/1820187

Pointer hwdev is being dereferenced when declaring hwif , however, later
on hwdev is being null checked, hence we have dereference before null
check error. Fix this by assigning hwif and pdef only once hwdev has
been null checked.

Detected by CoverityScan, CID#1485581 ("Dereference before null check")

Fixes: 4a61abb100c8 ("net-next/hinic:add rx checksum offload for HiNIC")
Signed-off-by: Colin Ian King <colin.king at canonical.com>
Signed-off-by: David S. Miller <davem at davemloft.net>
(cherry picked from commit e159e592872edc0536f55ec242dbc5b70a593265)
Signed-off-by: Ike Panhc <ike.pan at canonical.com>
---
 drivers/net/ethernet/huawei/hinic/hinic_port.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/net/ethernet/huawei/hinic/hinic_port.c b/drivers/net/ethernet/huawei/hinic/hinic_port.c
index e9f76e904610..122c93597268 100644
--- a/drivers/net/ethernet/huawei/hinic/hinic_port.c
+++ b/drivers/net/ethernet/huawei/hinic/hinic_port.c
@@ -414,14 +414,16 @@ int hinic_set_rx_csum_offload(struct hinic_dev *nic_dev, u32 en)
 {
 	struct hinic_checksum_offload rx_csum_cfg = {0};
 	struct hinic_hwdev *hwdev = nic_dev->hwdev;
-	struct hinic_hwif *hwif = hwdev->hwif;
-	struct pci_dev *pdev = hwif->pdev;
+	struct hinic_hwif *hwif;
+	struct pci_dev *pdev;
 	u16 out_size;
 	int err;
 
 	if (!hwdev)
 		return -EINVAL;
 
+	hwif = hwdev->hwif;
+	pdev = hwif->pdev;
 	rx_csum_cfg.func_id = HINIC_HWIF_FUNC_IDX(hwif);
 	rx_csum_cfg.rx_csum_offload = en;
 
-- 
2.17.1