[dpdk-stable] [PATCH] net/ena: fix false indication of bad L4 Rx csums

[Michal Krawczyk <mk@semihalf.com>]

Add checking of l4_csum_checked and frag flags before checking the
l4_csum_error flag.

In case of IP fragment/unchecked L4 csum - add PKT_RX_L4_CKSUM_UNKNOWN
flag to the indicated mbuf.

Fixes: 1173fca25af9 ("ena: add polling-mode driver")
Cc: stable@dpdk.org

Signed-off-by: Igor Chauskin <igorch@amazon.com>
Reviewed-by: Maciej Bielski <mba@semihalf.com>
Reviewed-by: Michal Krawczyk <mk@semihalf.com>
---
 drivers/net/ena/ena_ethdev.c | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/drivers/net/ena/ena_ethdev.c b/drivers/net/ena/ena_ethdev.c
index aa84fabc5..55b4982da 100644
--- a/drivers/net/ena/ena_ethdev.c
+++ b/drivers/net/ena/ena_ethdev.c
@@ -272,9 +272,14 @@ static inline void ena_rx_mbuf_prepare(struct rte_mbuf *mbuf,
 	else if (ena_rx_ctx->l3_proto == ENA_ETH_IO_L3_PROTO_IPV6)
 		packet_type |= RTE_PTYPE_L3_IPV6;
 
-	if (unlikely(ena_rx_ctx->l4_csum_err))
-		ol_flags |= PKT_RX_L4_CKSUM_BAD;
+	if (!ena_rx_ctx->l4_csum_checked)
+		ol_flags |= PKT_RX_L4_CKSUM_UNKNOWN;
+	else
+		if (unlikely(ena_rx_ctx->l4_csum_err) && !ena_rx_ctx->frag)
+			ol_flags |= PKT_RX_L4_CKSUM_BAD;
+		else
+			ol_flags |= PKT_RX_L4_CKSUM_UNKNOWN;
+
 	if (unlikely(ena_rx_ctx->l3_csum_err))
 		ol_flags |= PKT_RX_IP_CKSUM_BAD;
 
-- 
2.20.1