From b019223d0ac1b9b3c078892edb3a57e199ecde9b Mon Sep 17 00:00:00 2001
From: Hao Chen <chenhao288@hisilicon.com>
Date: Sat, 26 Mar 2022 17:51:03 +0800
Subject: [PATCH 04/19] net: hns3: add netdev reset check for
 hns3_set_tunable()
Git-commit: f5cd60169f981ca737c9e49c446506dfafc90a35
Patch-mainline: v5.18-rc1
References: git-fixes

When pci device reset failed, it does uninit operation and priv->ring
is NULL, it causes accessing NULL pointer error.

Add netdev reset check for hns3_set_tunable() to fix it.

Fixes: 99f6b5fb5f63 ("net: hns3: use bounce buffer when rx page can not be reused")
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>
Signed-off-by: Denis Kirjanov <denis.kirjanov@suse.com>
---
 drivers/net/ethernet/hisilicon/hns3/hns3_ethtool.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/drivers/net/ethernet/hisilicon/hns3/hns3_ethtool.c b/drivers/net/ethernet/hisilicon/hns3/hns3_ethtool.c
index 0a81bcc7d61c..759d2949c7d7 100644
--- a/drivers/net/ethernet/hisilicon/hns3/hns3_ethtool.c
+++ b/drivers/net/ethernet/hisilicon/hns3/hns3_ethtool.c
@@ -1730,6 +1730,11 @@ static int hns3_set_tunable(struct net_device *netdev,
 	struct hnae3_handle *h = priv->ae_handle;
 	int i, ret = 0;
 
+	if (hns3_nic_resetting(netdev) || !priv->ring) {
+		netdev_err(netdev, "failed to set tunable value, dev resetting!");
+		return -EBUSY;
+	}
+
 	switch (tuna->id) {
 	case ETHTOOL_TX_COPYBREAK:
 		priv->tx_copybreak = *(u32 *)data;
-- 
2.16.4