[dpdk-dev] [PATCH] net/enic: fix possible Rx corruption

[John Daley <johndale@cisco.com>]

Initialize the mbuf data offset to RTE_PKTMBUF_HEADROOM as the
enic takes ownership of them. If allocated mbufs had some offset
other than RTE_PKTMBUF_HEADROOM, the application would read mbuf
data starting at the wrong place and misinterpret the packet.

Fixes: 856d7ba7ed22 ("net/enic: support scattered Rx")

Reviewed-by: Nelson Escobar <neescoba@cisco.com>
Signed-off-by: John Daley <johndale@cisco.com>
---

Please include this patch in 16.07 since the bug found in late testing
can cause data corruption.

 drivers/net/enic/enic_main.c | 1 +
 drivers/net/enic/enic_rxtx.c | 1 +
 2 files changed, 2 insertions(+)

diff --git a/drivers/net/enic/enic_main.c b/drivers/net/enic/enic_main.c
index 542f095..b4ca371 100644
--- a/drivers/net/enic/enic_main.c
+++ b/drivers/net/enic/enic_main.c
@@ -317,6 +317,7 @@ enic_alloc_rx_queue_mbufs(struct enic *enic, struct vnic_rq *rq)
 			return -ENOMEM;
 		}
 
+		mb->data_off = RTE_PKTMBUF_HEADROOM;
 		dma_addr = (dma_addr_t)(mb->buf_physaddr
 			   + RTE_PKTMBUF_HEADROOM);
 		rq_enet_desc_enc(rqd, dma_addr,
diff --git a/drivers/net/enic/enic_rxtx.c b/drivers/net/enic/enic_rxtx.c
index 845a8e6..50f0b28 100644
--- a/drivers/net/enic/enic_rxtx.c
+++ b/drivers/net/enic/enic_rxtx.c
@@ -300,6 +300,7 @@ enic_recv_pkts(void *rx_queue, struct rte_mbuf **rx_pkts,
 			(struct cq_enet_rq_desc *)&cqd);
 
 		/* Push descriptor for newly allocated mbuf */
+		nmb->data_off = RTE_PKTMBUF_HEADROOM;
 		dma_addr = (dma_addr_t)(nmb->buf_physaddr +
 					RTE_PKTMBUF_HEADROOM);
 		rq_enet_desc_enc(rqd_ptr, dma_addr,
-- 
2.7.0