[PATCH 4.19 160/267] net/mlx5e: IPoIB, Drop multicast packets that this interface sent

[Greg Kroah-Hartman]

From: Erez Shitrit <ere...@mellanox.com>

[ Upstream commit 8b46d424a743ddfef8056d5167f13ee7ebd1dcad ]

After enabled loopback packets for IPoIB, we need to drop these packets
that this HCA has replicated and came back to the same interface that
sent them.

Fixes: 4c6c615e3f30 ("net/mlx5e: IPoIB, Add PKEY child interface nic profile")
Signed-off-by: Erez Shitrit <ere...@mellanox.com>
Reviewed-by: Alex Vesker <va...@mellanox.com>
Signed-off-by: Saeed Mahameed <sae...@mellanox.com>
Signed-off-by: Sasha Levin <sas...@kernel.org>
---
 drivers/net/ethernet/mellanox/mlx5/core/en_rx.c | 15 ++++++++++++---
 1 file changed, 12 insertions(+), 3 deletions(-)

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_rx.c 
b/drivers/net/ethernet/mellanox/mlx5/core/en_rx.c
index 044687a1f27c..9d86e49a7f44 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/en_rx.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_rx.c
@@ -1314,6 +1314,7 @@ out:
 
 #ifdef CONFIG_MLX5_CORE_IPOIB
 
+#define MLX5_IB_GRH_SGID_OFFSET 8
 #define MLX5_IB_GRH_DGID_OFFSET 24
 #define MLX5_GID_SIZE           16
 
@@ -1327,6 +1328,7 @@ static inline void mlx5i_complete_rx_cqe(struct mlx5e_rq 
*rq,
        struct net_device *netdev;
        struct mlx5e_priv *priv;
        char *pseudo_header;
+       u32 flags_rqpn;
        u32 qpn;
        u8 *dgid;
        u8 g;
@@ -1347,7 +1349,8 @@ static inline void mlx5i_complete_rx_cqe(struct mlx5e_rq 
*rq,
        priv = mlx5i_epriv(netdev);
        tstamp = &priv->tstamp;
 
-       g = (be32_to_cpu(cqe->flags_rqpn) >> 28) & 3;
+       flags_rqpn = be32_to_cpu(cqe->flags_rqpn);
+       g = (flags_rqpn >> 28) & 3;
        dgid = skb->data + MLX5_IB_GRH_DGID_OFFSET;
        if ((!g) || dgid[0] != 0xff)
                skb->pkt_type = PACKET_HOST;
@@ -1356,9 +1359,15 @@ static inline void mlx5i_complete_rx_cqe(struct mlx5e_rq 
*rq,
        else
                skb->pkt_type = PACKET_MULTICAST;
 
-       /* TODO: IB/ipoib: Allow mcast packets from other VFs
-        * 68996a6e760e5c74654723eeb57bf65628ae87f4
+       /* Drop packets that this interface sent, ie multicast packets
+        * that the HCA has replicated.
         */
+       if (g && (qpn == (flags_rqpn & 0xffffff)) &&
+           (memcmp(netdev->dev_addr + 4, skb->data + MLX5_IB_GRH_SGID_OFFSET,
+                   MLX5_GID_SIZE) == 0)) {
+               skb->dev = NULL;
+               return;
+       }
 
        skb_pull(skb, MLX5_IB_GRH_BYTES);
 
-- 
2.25.1