[dpdk-dev] [PATCH v2] virtio: fix buffer leak on vlan insert

[Stephen Hemminger <stephen@networkplumber.org>]

The function rte_vlan_insert may allocate a new buffer for the
vlan header and return a different mbuf than originally passed.
In this case, the stored mbuf in txm[] array could point to wrong
buffer.

Fixes: dd856dfcb9e7 ("virtio: use any layout on Tx")
Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
---
v2 - catch a couple more places.
     The virtio code needs some refactoring to not have 3 copies of same
     loop...

 drivers/net/virtio/virtio_rxtx.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/drivers/net/virtio/virtio_rxtx.c b/drivers/net/virtio/virtio_rxtx.c
index e6f3706d6fe1..8c56f238f965 100644
--- a/drivers/net/virtio/virtio_rxtx.c
+++ b/drivers/net/virtio/virtio_rxtx.c
@@ -2003,6 +2003,8 @@ virtio_xmit_pkts_packed(void *tx_queue, struct rte_mbuf **tx_pkts,
 				rte_pktmbuf_free(txm);
 				continue;
 			}
+			/* vlan_insert may add a header mbuf */
+			tx_pkts[nb_tx] = txm;
 		}
 
 		/* optimize ring usage */
@@ -2090,6 +2092,8 @@ virtio_xmit_pkts(void *tx_queue, struct rte_mbuf **tx_pkts, uint16_t nb_pkts)
 				rte_pktmbuf_free(txm);
 				continue;
 			}
+			/* vlan_insert may add a header mbuf */
+			tx_pkts[nb_tx] = txm;
 		}
 
 		/* optimize ring usage */
@@ -2193,6 +2197,8 @@ virtio_xmit_pkts_inorder(void *tx_queue,
 				rte_pktmbuf_free(txm);
 				continue;
 			}
+			/* vlan_insert may add a header mbuf */
+			tx_pkts[nb_tx] = txm;
 		}
 
 		/* optimize ring usage */
-- 
2.17.1