Add const attribute to filter argument to make clear it is no
longer modified.
Signed-off-by: NEric Dumazet <edumazet@google.com>
Acked-by: NDaniel Borkmann <dborkman@redhat.com>
Acked-by: NAlexei Starovoitov <ast@plumgrid.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>