From: Ido Schimmel <idosch@mellanox.com>
Date: Thu, 17 Oct 2019 10:11:03 +0300
Subject: mlxsw: spectrum_trap: Push Ethernet header before reporting trap
Patch-mainline: v5.4-rc4
Git-commit: 2e978795bb4c14293bf6ecf32621d32529706aef
References: bsc#1154488

devlink maintains packets and bytes statistics for each trap. Since
eth_type_trans() was called to set the skb's protocol, the data pointer
no longer points to the start of the packet and the bytes accounting is
off by 14 bytes.

Fix this by pushing the skb's data pointer to the start of the packet.

Fixes: b5ce611fd96e ("mlxsw: spectrum: Add devlink-trap support")
Reported-by: Alex Kushnarov <alexanderk@mellanox.com>
Tested-by: Alex Kushnarov <alexanderk@mellanox.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Acked-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
 drivers/net/ethernet/mellanox/mlxsw/spectrum_trap.c |    1 +
 1 file changed, 1 insertion(+)

--- a/drivers/net/ethernet/mellanox/mlxsw/spectrum_trap.c
+++ b/drivers/net/ethernet/mellanox/mlxsw/spectrum_trap.c
@@ -99,6 +99,7 @@ static void mlxsw_sp_rx_drop_listener(st
 	devlink = priv_to_devlink(mlxsw_sp->core);
 	in_devlink_port = mlxsw_core_port_devlink_port_get(mlxsw_sp->core,
 							   local_port);
+	skb_push(skb, ETH_HLEN);
 	devlink_trap_report(devlink, skb, trap_ctx, in_devlink_port);
 	consume_skb(skb);
 }