ipv4: ensure rcu_read_lock() in cipso_v4_error()

ipv4: ensure rcu_read_lock() in cipso_v4_error()

commit 2ba57e414a722f62d2c86f73f8e79d47f54af488 upstream.

Similarly to commit ff95da02b598 ("ipv4: ensure rcu_read_lock() in
ipv4_link_failure()"), __ip_options_compile() must be called under rcu
protection.

Fixes: 51a0bb5d9767 ("net: avoid use IPCB in cipso_v4_error")
Suggested-by: Guillaume Nault <gnault@redhat.com>
Signed-off-by: Matteo Croce <mcroce@redhat.com>
Acked-by: Paul Moore <paul@paul-moore.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>