vxcan: enable local echo for sent CAN frames

[ Upstream commit 259bdba27e32368b4404f69d613b1c1014c07cbf ]

The vxcan driver provides a pair of virtual CAN interfaces to exchange
CAN traffic between different namespaces - analogue to veth.

In opposite to the vcan driver the local sent CAN traffic on this interface
is not echo'ed back but only sent to the remote peer. This is unusual and
can be easily fixed by removing IFF_ECHO from the netdevice flags that
are set for vxcan interfaces by default at startup.

Without IFF_ECHO set on driver level, the local sent CAN frames are echo'ed
in af_can.c in can_send(). This patch makes vxcan interfaces adopt the
same local echo behavior and procedures as known from the vcan interfaces.

Fixes: a8f820a380a2 ("can: add Virtual CAN Tunnel driver (vxcan)")
Link: https://lore.kernel.org/all/20220309120416.83514-5-socketcan@hartkopp.net
Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/drivers/net/can/vxcan.c b/drivers/net/can/vxcan.c
index 8861a7d875e7e538556f2aa6aff37a0b49130656..be5566168d0f3da88ec8555d8e1bcd6fddb8cc92 100644 (file)
--- a/drivers/net/can/vxcan.c
+++ b/drivers/net/can/vxcan.c
@@ -148,7 +148,7 @@ static void vxcan_setup(struct net_device *dev)
        dev->hard_header_len    = 0;
        dev->addr_len           = 0;
        dev->tx_queue_len       = 0;
-       dev->flags              = (IFF_NOARP|IFF_ECHO);
+       dev->flags              = IFF_NOARP;
        dev->netdev_ops         = &vxcan_netdev_ops;
        dev->needs_free_netdev  = true;