vxlan: check return value of gro_cells_init()

stable inclusion
from linux-4.19.114
commit facf9c7ecc2f0d8e8c65e4d532f690dc5e7aa659

--------------------------------

[ Upstream commit 384d91c2 ]

gro_cells_init() returns error if memory allocation is failed.
But the vxlan module doesn't check the return value of gro_cells_init().

Fixes: 58ce31cc ("vxlan: GRO support at tunnel layer")`
Signed-off-by: NTaehee Yoo <ap420073@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: NYang Yingliang <yangyingliang@huawei.com>
Signed-off-by: NLi Aichun <liaichun@huawei.com>
Reviewed-by: Nguodeqing <geffrey.guo@huawei.com>
Signed-off-by: NYang Yingliang <yangyingliang@huawei.com>

drivers/net/vxlan.c

@@ -2449,10 +2449,19 @@ static void vxlan_vs_add_dev(struct vxlan_sock *vs, struct vxlan_dev *vxlan,
 /* Setup stats when device is created */
 static int vxlan_init(struct net_device *dev)
 {
+	struct vxlan_dev *vxlan = netdev_priv(dev);
+	int err;
+
 	dev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats);
 	if (!dev->tstats)
 		return -ENOMEM;
 
+	err = gro_cells_init(&vxlan->gro_cells, dev);
+	if (err) {
+		free_percpu(dev->tstats);
+		return err;
+	}
+
 	return 0;
 }
 
@@ -2710,8 +2719,6 @@ static void vxlan_setup(struct net_device *dev)
 
 	vxlan->dev = dev;
 
-	gro_cells_init(&vxlan->gro_cells, dev);
-
 	for (h = 0; h < FDB_HASH_SIZE; ++h)
 		INIT_HLIST_HEAD(&vxlan->fdb_head[h]);
 }