virtio: fix the index issue

Type: fix

Fixes: 587f9130424fd451e4ba823240d02f655fb197d1

Change-Id: I230993a54c84e22e324de2a8defeda83c517d733
Signed-off-by: Mohsin Kazmi <sykazmi@cisco.com>

diff --git a/src/vnet/devices/virtio/device.c b/src/vnet/devices/virtio/device.c
index cba13f9..add82b7 100644 (file)
--- a/src/vnet/devices/virtio/device.c
+++ b/src/vnet/devices/virtio/device.c
@@ -707,13 +707,19 @@ retry:
 
   if (vif->type == VIRTIO_IF_TYPE_TAP)
     n_left = virtio_interface_tx_inline (vm, node, vif, vring,
-                                        VIRTIO_IF_TYPE_TAP, buffers, n_left);
+                                        VIRTIO_IF_TYPE_TAP,
+                                        &buffers[frame->n_vectors - n_left],
+                                        n_left);
   else if (vif->type == VIRTIO_IF_TYPE_PCI)
     n_left = virtio_interface_tx_inline (vm, node, vif, vring,
-                                        VIRTIO_IF_TYPE_PCI, buffers, n_left);
+                                        VIRTIO_IF_TYPE_PCI,
+                                        &buffers[frame->n_vectors - n_left],
+                                        n_left);
   else if (vif->type == VIRTIO_IF_TYPE_TUN)
     n_left = virtio_interface_tx_inline (vm, node, vif, vring,
-                                        VIRTIO_IF_TYPE_TUN, buffers, n_left);
+                                        VIRTIO_IF_TYPE_TUN,
+                                        &buffers[frame->n_vectors - n_left],
+                                        n_left);
   else
     ASSERT (0);
 
@@ -722,15 +728,17 @@ retry:
 
   if (vif->packet_buffering && n_left)
     {
-      u16 n_buffered =
-       virtio_vring_buffering_store_packets (vring->buffering, buffers,
-                                             n_left);
+      u16 n_buffered = virtio_vring_buffering_store_packets (vring->buffering,
+                                                            &buffers
+                                                            [frame->n_vectors
+                                                             - n_left],
+                                                            n_left);
       buffers += n_buffered;
       n_left -= n_buffered;
     }
   if (n_left)
     virtio_interface_drop_inline (vm, node->node_index,
-                                 buffers + frame->n_vectors - n_left, n_left,
+                                 &buffers[frame->n_vectors - n_left], n_left,
                                  VIRTIO_TX_ERROR_NO_FREE_SLOTS);
 
   clib_spinlock_unlock_if_init (&vring->lockp);