From: Liang He <windhl@126.com>
Date: Wed, 15 Mar 2023 14:00:21 +0800
Subject: [PATCH] ethernet: sun: add check for the mdesc_grab()
References: bsc#1012628
Patch-mainline: 6.2.8
Git-commit: 90de546d9a0b3c771667af18bb3f80567eabb89b

[ Upstream commit 90de546d9a0b3c771667af18bb3f80567eabb89b ]

In vnet_port_probe() and vsw_port_probe(), we should
check the return value of mdesc_grab() as it may
return NULL which can caused NPD bugs.

Fixes: 5d01fa0c6bd8 ("ldmvsw: Add ldmvsw.c driver code")
Fixes: 43fdf27470b2 ("[SPARC64]: Abstract out mdesc accesses for better MD update handling.")
Signed-off-by: Liang He <windhl@126.com>
Reviewed-by: Piotr Raczynski <piotr.raczynski@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
---
 drivers/net/ethernet/sun/ldmvsw.c  | 3 +++
 drivers/net/ethernet/sun/sunvnet.c | 3 +++
 2 files changed, 6 insertions(+)

diff --git a/drivers/net/ethernet/sun/ldmvsw.c b/drivers/net/ethernet/sun/ldmvsw.c
index 8addee6d..734a817d 100644
--- a/drivers/net/ethernet/sun/ldmvsw.c
+++ b/drivers/net/ethernet/sun/ldmvsw.c
@@ -287,6 +287,9 @@ static int vsw_port_probe(struct vio_dev *vdev, const struct vio_device_id *id)
 
 	hp = mdesc_grab();
 
+	if (!hp)
+		return -ENODEV;
+
 	rmac = mdesc_get_property(hp, vdev->mp, remote_macaddr_prop, &len);
 	err = -ENODEV;
 	if (!rmac) {
diff --git a/drivers/net/ethernet/sun/sunvnet.c b/drivers/net/ethernet/sun/sunvnet.c
index fe86fbd5..e220620d 100644
--- a/drivers/net/ethernet/sun/sunvnet.c
+++ b/drivers/net/ethernet/sun/sunvnet.c
@@ -433,6 +433,9 @@ static int vnet_port_probe(struct vio_dev *vdev, const struct vio_device_id *id)
 
 	hp = mdesc_grab();
 
+	if (!hp)
+		return -ENODEV;
+
 	vp = vnet_find_parent(hp, vdev->mp, vdev);
 	if (IS_ERR(vp)) {
 		pr_err("Cannot find port parent vnet\n");
-- 
2.35.3