[PATCH 3.18 104/145] vxlan: correctly validate VXLAN ID against VXLAN_N_VID

Greg Kroah-Hartman
2017-04-16T10:56:26Z

From: Matthias Schiffer <mschiffer@universe-factory.net>

commit 4e37d6911f36545b286d15073f6f2222f840e81c upstream.

The incorrect check caused an off-by-one error: the maximum VID 0xffffff
was unusable.

Fixes: d342894c5d2f ("vxlan: virtual extensible lan")
Signed-off-by: Matthias Schiffer <mschiffer@universe-factory.net>
Acked-by: Jiri Benc <jbenc@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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

--- a/drivers/net/vxlan.c
+++ b/drivers/net/vxlan.c
@@ -2260,7 +2260,7 @@ static int vxlan_validate(struct nlattr

if (data[IFLA_VXLAN_ID]) {
__u32 id = nla_get_u32(data[IFLA_VXLAN_ID]);
- if (id >= VXLAN_VID_MASK)
+ if (id >= VXLAN_N_VID)
return -ERANGE;
}