[PATCH 5.4 84/86] net: dsa: b53: fix an off by one in checking "vlan->vid"

[Greg Kroah-Hartman]

From: Dan Carpenter <dan.carpenter@xxxxxxxxxx>

commit 8e4052c32d6b4b39c1e13c652c7e33748d447409 upstream.

The > comparison should be >= to prevent accessing one element beyond
the end of the dev->vlans[] array in the caller function, b53_vlan_add().
The "dev->vlans" array is allocated in the b53_switch_init() function
and it has "dev->num_vlans" elements.

Fixes: a2482d2ce349 ("net: dsa: b53: Plug in VLAN support")
Signed-off-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
Acked-by: Florian Fainelli <f.fainelli@xxxxxxxxx>
Link: https://lore.kernel.org/r/YAbxI97Dl/pmBy5V@mwanda
Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
 drivers/net/dsa/b53/b53_common.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/drivers/net/dsa/b53/b53_common.c
+++ b/drivers/net/dsa/b53/b53_common.c
@@ -1330,7 +1330,7 @@ int b53_vlan_prepare(struct dsa_switch *
 	if ((is5325(dev) || is5365(dev)) && vlan->vid_begin == 0)
 		return -EOPNOTSUPP;
 
-	if (vlan->vid_end > dev->num_vlans)
+	if (vlan->vid_end >= dev->num_vlans)
 		return -ERANGE;
 
 	b53_enable_vlan(dev, true, ds->vlan_filtering);