ip_tunnel: Fix off-by-one error in forming dev name.

As Ben pointed out following patch fixes bug in checking device
name length limits while forming tunnel device name.

CC: Ben Hutchings <bhutchings@solarflare.com>
Signed-off-by: Pravin B Shelar <pshelar@nicira.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/net/ipv4/ip_tunnel.c b/net/ipv4/ip_tunnel.c
index 9d96b6853f219e792b680319cc9d591db1f8fcf0..e4147ec1665a7af9c9661a12712babdf4bfd29ea 100644 (file)
--- a/net/ipv4/ip_tunnel.c
+++ b/net/ipv4/ip_tunnel.c
@@ -284,7 +284,7 @@ static struct net_device *__ip_tunnel_create(struct net *net,
        if (parms->name[0])
                strlcpy(name, parms->name, IFNAMSIZ);
        else {
        if (parms->name[0])
                strlcpy(name, parms->name, IFNAMSIZ);
        else {

-               if (strlen(ops->kind) + 3 >= IFNAMSIZ) {
+               if (strlen(ops->kind) > (IFNAMSIZ - 3)) {

                        err = -E2BIG;
                        goto failed;
                }
                        err = -E2BIG;
                        goto failed;
                }