[dpdk-dev] [PATCH v3 09/10] vmxnet3: add check for jumbo segment

[Stephen Hemminger <stephen@networkplumber.org>]

From: Stephen Hemminger <shemming@brocade.com>

It is possible that some rogue application might pass a segment
larger than 16K to the vmxnet3 transmit routine. In which case
just drop it and increment counter.

Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
---
 lib/librte_pmd_vmxnet3/vmxnet3_ring.h |  1 +
 lib/librte_pmd_vmxnet3/vmxnet3_rxtx.c | 18 ++++++++++++++++++
 2 files changed, 19 insertions(+)

diff --git a/lib/librte_pmd_vmxnet3/vmxnet3_ring.h b/lib/librte_pmd_vmxnet3/vmxnet3_ring.h
index 55ceadf..5cdcb23 100644
--- a/lib/librte_pmd_vmxnet3/vmxnet3_ring.h
+++ b/lib/librte_pmd_vmxnet3/vmxnet3_ring.h
@@ -126,6 +126,7 @@ struct vmxnet3_txq_stats {
 				     * different reasons
 				     */
 	uint64_t	drop_too_many_segs;
+	uint64_t	drop_too_big;
 	uint64_t	drop_tso;
 	uint64_t	tx_ring_full;
 };
diff --git a/lib/librte_pmd_vmxnet3/vmxnet3_rxtx.c b/lib/librte_pmd_vmxnet3/vmxnet3_rxtx.c
index 3bd13ef..f6c3452 100644
--- a/lib/librte_pmd_vmxnet3/vmxnet3_rxtx.c
+++ b/lib/librte_pmd_vmxnet3/vmxnet3_rxtx.c
@@ -327,6 +327,17 @@ vmxnet3_tq_tx_complete(vmxnet3_tx_queue_t *txq)
 	PMD_TX_LOG(DEBUG, "Processed %d tx comps & command descs.", completed);
 }
 
+static inline int
+vmxnet3_seg_too_big(const struct rte_mbuf *m)
+{
+	do {
+		if (m->data_len > VMXNET3_MAX_TX_BUF_SIZE)
+			return 1;
+	} while  ((m = m->next) != NULL);
+
+	return 0;
+}
+
 uint16_t
 vmxnet3_xmit_pkts(void *tx_queue, struct rte_mbuf **tx_pkts,
 		  uint16_t nb_pkts)
@@ -353,6 +364,13 @@ vmxnet3_xmit_pkts(void *tx_queue, struct rte_mbuf **tx_pkts,
 		/* Is this packet execessively fragmented, then drop */
 		if (unlikely(txm->nb_segs > VMXNET3_MAX_TXD_PER_PKT)) {
 			++txq->stats.drop_too_many_segs;
+			goto drop;
+		}
+
+		/* Check for case of monster segment */
+		if (unlikely(vmxnet3_seg_too_big(txm))) {
+			++txq->stats.drop_too_big;
+		drop:
 			++txq->stats.drop_total;
 			rte_pktmbuf_free(txm);
 			++nb_tx;
-- 
2.1.4