[PATCH net-next 6/9] net: hns3: fix vf id check issue when add flow director rule

[Peng Li]

From: Jian Shen <shenjian15@xxxxxxxxxx>

When add flow director fule for vf, the vf id is used as array
subscript before valid checking, which may cause memory overflow.

Fixes: dd74f815dd41 ("net: hns3: Add support for rule add/delete for flow director")
Signed-off-by: Jian Shen <shenjian15@xxxxxxxxxx>
Signed-off-by: Peng Li <lipeng321@xxxxxxxxxx>
---
 drivers/net/ethernet/hisilicon/hns3/hns3pf/hclge_main.c | 14 +++++++-------
 1 file changed, 7 insertions(+), 7 deletions(-)

diff --git a/drivers/net/ethernet/hisilicon/hns3/hns3pf/hclge_main.c b/drivers/net/ethernet/hisilicon/hns3/hns3pf/hclge_main.c
index 98ae282..9f89858 100644
--- a/drivers/net/ethernet/hisilicon/hns3/hns3pf/hclge_main.c
+++ b/drivers/net/ethernet/hisilicon/hns3/hns3pf/hclge_main.c
@@ -4677,6 +4677,13 @@ static int hclge_add_fd_entry(struct hnae3_handle *handle,
 		u8 vf = ethtool_get_flow_spec_ring_vf(fs->ring_cookie);
 		u16 tqps;
 
+		if (vf > hdev->num_req_vfs) {
+			dev_err(&hdev->pdev->dev,
+				"Error: vf id (%d) > max vf num (%d)\n",
+				vf, hdev->num_req_vfs);
+			return -EINVAL;
+		}
+
 		dst_vport_id = vf ? hdev->vport[vf].vport_id : vport->vport_id;
 		tqps = vf ? hdev->vport[vf].alloc_tqps : vport->alloc_tqps;
 
@@ -4687,13 +4694,6 @@ static int hclge_add_fd_entry(struct hnae3_handle *handle,
 			return -EINVAL;
 		}
 
-		if (vf > hdev->num_req_vfs) {
-			dev_err(&hdev->pdev->dev,
-				"Error: vf id (%d) > max vf num (%d)\n",
-				vf, hdev->num_req_vfs);
-			return -EINVAL;
-		}
-
 		action = HCLGE_FD_ACTION_ACCEPT_PACKET;
 		q_index = ring;
 	}
-- 
1.9.1