[PATCH net 5/6] net: hns3: fix the exception when query imp info

[Guangbin Huang]

From: Jiaran Zhang <zhangjiaran@xxxxxxxxxx>

When the command for querying imp info is issued to the firmware,
if the firmware does not support the command, the returned value
of bd num is 0.
Add protection mechanism before alloc memory to prevent apply for
0-length memory.

Fixes: 0b198b0d80ea ("net: hns3: refactor dump m7 info of debugfs")
Signed-off-by: Jiaran Zhang <zhangjiaran@xxxxxxxxxx>
Signed-off-by: Guangbin Huang <huangguangbin2@xxxxxxxxxx>
---
 drivers/net/ethernet/hisilicon/hns3/hns3pf/hclge_debugfs.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/drivers/net/ethernet/hisilicon/hns3/hns3pf/hclge_debugfs.c b/drivers/net/ethernet/hisilicon/hns3/hns3pf/hclge_debugfs.c
index 68ed1715ac52..87d96f82c318 100644
--- a/drivers/net/ethernet/hisilicon/hns3/hns3pf/hclge_debugfs.c
+++ b/drivers/net/ethernet/hisilicon/hns3/hns3pf/hclge_debugfs.c
@@ -1724,6 +1724,10 @@ hclge_dbg_get_imp_stats_info(struct hclge_dev *hdev, char *buf, int len)
 	}
 
 	bd_num = le32_to_cpu(req->bd_num);
+	if (!bd_num) {
+		dev_err(&hdev->pdev->dev, "imp statistics bd number is 0!\n");
+		return -EINVAL;
+	}
 
 	desc_src = kcalloc(bd_num, sizeof(struct hclge_desc), GFP_KERNEL);
 	if (!desc_src)
-- 
2.33.0