From: Hao Chen <chenhao288@hisilicon.com>
Date: Sat, 26 Mar 2022 17:51:04 +0800
Subject: net: hns3: add NULL pointer check for hns3_set/get_ringparam()
Patch-mainline: v5.18-rc1
Git-commit: 4d07c5936c2508ddd1cfd49b0a91d94cb4d1f0e8
References: git-fixes

When pci devices init failed and haven't reinit, priv->ring is
NULL and hns3_set/get_ringparam() will access priv->ring. it
causes call trace.

So, add NULL pointer check for hns3_set/get_ringparam() to
avoid this situation.

Fixes: 5668abda0931 ("net: hns3: add support for set_ringparam")
Signed-off-by: Hao Chen <chenhao288@hisilicon.com>
Signed-off-by: Guangbin Huang <huangguangbin2@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Acked-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
 drivers/net/ethernet/hisilicon/hns3/hns3_ethtool.c |   11 ++++++++---
 1 file changed, 8 insertions(+), 3 deletions(-)

--- a/drivers/net/ethernet/hisilicon/hns3/hns3_ethtool.c
+++ b/drivers/net/ethernet/hisilicon/hns3/hns3_ethtool.c
@@ -649,8 +649,8 @@ static void hns3_get_ringparam(struct ne
 	struct hnae3_handle *h = priv->ae_handle;
 	int queue_num = h->kinfo.num_tqps;
 
-	if (hns3_nic_resetting(netdev)) {
-		netdev_err(netdev, "dev resetting!");
+	if (hns3_nic_resetting(netdev) || !priv->ring) {
+		netdev_err(netdev, "failed to get ringparam value, due to dev resetting or uninited\n");
 		return;
 	}
 
@@ -1066,8 +1066,13 @@ static struct hns3_enet_ring *hns3_backu
 static int hns3_check_ringparam(struct net_device *ndev,
 				struct ethtool_ringparam *param)
 {
-	if (hns3_nic_resetting(ndev))
+	struct hns3_nic_priv *priv = netdev_priv(ndev);
+
+	if (hns3_nic_resetting(ndev) || !priv->ring) {
+		netdev_err(ndev, "failed to set ringparam value, due to dev resetting or uninited\n");
 		return -EBUSY;
+	}
+
 
 	if (param->rx_mini_pending || param->rx_jumbo_pending)
 		return -EINVAL;