[dpdk-dev] [PATCH 3/3] virtio: fix possible NULL dereference

[Stephen Hemminger]

Found by Coverity. In virtio_dev_queue_release if the queue pointer is
NULL, then driver is dereferencing it to get hw pointer.
Also, don't do useless assignment

Signed-off-by: Stephen Hemminger <stephen at networkplumber.org>
---
 drivers/net/virtio/virtio_ethdev.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/net/virtio/virtio_ethdev.c 
b/drivers/net/virtio/virtio_ethdev.c
index 338d891..914c73d 100644
--- a/drivers/net/virtio/virtio_ethdev.c
+++ b/drivers/net/virtio/virtio_ethdev.c
@@ -239,15 +239,15 @@ virtio_set_multiple_queues(struct rte_eth_dev *dev, 
uint16_t nb_queues)

 void
 virtio_dev_queue_release(struct virtqueue *vq) {
-       struct virtio_hw *hw = vq->hw;

        if (vq) {
+               struct virtio_hw *hw = vq->hw;
+
                /* Select and deactivate the queue */
                VIRTIO_WRITE_REG_2(hw, VIRTIO_PCI_QUEUE_SEL, vq->queue_id);
                VIRTIO_WRITE_REG_4(hw, VIRTIO_PCI_QUEUE_PFN, 0);

                rte_free(vq);
-               vq = NULL;
        }
 }

-- 
2.1.4