[PATCH 5.10 249/452] hv_netvsc: Fix potential dereference of NULL pointer

[Greg Kroah-Hartman]

From: Yongzhi Liu <lyz_cs@xxxxxxxxxx>

[ Upstream commit eb4c0788964730d12e8dd520bd8f5217ca48321c ]

The return value of netvsc_devinfo_get()
needs to be checked to avoid use of NULL
pointer in case of an allocation failure.

Fixes: 0efeea5fb153 ("hv_netvsc: Add the support of hibernation")
Signed-off-by: Yongzhi Liu <lyz_cs@xxxxxxxxxx>
Reviewed-by: Haiyang Zhang <haiyangz@xxxxxxxxxxxxx>
Link: https://lore.kernel.org/r/1652962188-129281-1-git-send-email-lyz_cs@xxxxxxxxxx
Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
 drivers/net/hyperv/netvsc_drv.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/drivers/net/hyperv/netvsc_drv.c b/drivers/net/hyperv/netvsc_drv.c
index e3676386d0ee..18484370da0d 100644
--- a/drivers/net/hyperv/netvsc_drv.c
+++ b/drivers/net/hyperv/netvsc_drv.c
@@ -2629,7 +2629,10 @@ static int netvsc_suspend(struct hv_device *dev)
 
 	/* Save the current config info */
 	ndev_ctx->saved_netvsc_dev_info = netvsc_devinfo_get(nvdev);
-
+	if (!ndev_ctx->saved_netvsc_dev_info) {
+		ret = -ENOMEM;
+		goto out;
+	}
 	ret = netvsc_detach(net, nvdev);
 out:
 	rtnl_unlock();
-- 
2.35.1