nfp: refuse offloading filters that redirects to upper devices

Previously we did not ensure that a netdev is a representative netdev
before dereferencing its private data. This can occur when an upper netdev
is created on a representative netdev. This patch corrects this by first
ensuring that the netdev is a representative netdev before using it.
Checking only switchdev_port_same_parent_id is not sufficient to ensure
that we can safely use the netdev. Failing to check that the netdev is also
a representative netdev would result in incorrect dereferencing.

Fixes: 1a1e586f54bf ("nfp: add basic action capabilities to flower offloads")
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Pieter Jansen van Vuuren <pieter.jansenvanvuuren@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/ethernet/netronome/nfp/flower/action.c b/drivers/net/ethernet/netronome/nfp/flower/action.c
index db9750695dc7f63cf8d9861026995098aa9cbcf0..8ea9320014ee78141f71f883452bb81926e208c6 100644 (file)
--- a/drivers/net/ethernet/netronome/nfp/flower/action.c
+++ b/drivers/net/ethernet/netronome/nfp/flower/action.c
@@ -110,6 +110,8 @@ nfp_fl_output(struct nfp_fl_output *output, const struct tc_action *action,
         */
        if (!switchdev_port_same_parent_id(in_dev, out_dev))
                return -EOPNOTSUPP;
+       if (!nfp_netdev_is_nfp_repr(out_dev))
+               return -EOPNOTSUPP;
 
        output->port = cpu_to_be32(nfp_repr_get_port_id(out_dev));
        if (!output->port)