[ Upstream commit 5dbd5068 ]

There is a hole in struct ip6_tnl_parm2, so we have to
zero the struct on stack before copying it to user-space.

Cc: David S. Miller <davem@davemloft.net>
Signed-off-by: Cong Wang <amwang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>