vhost: fix initialization of temporary header

This patch fixs coverity issue by adding initialization step before
using temporary virtio header.

Coverity issue: 366181
Fixes: fb3815cc614d ("vhost: handle virtually non-contiguous buffers in Rx-mrg")
Cc: stable@dpdk.org
Signed-off-by: Marvin Liu <yong.liu@intel.com>
Reviewed-by: Maxime Coquelin <maxime.coquelin@redhat.com>

diff --git a/lib/librte_vhost/virtio_net.c b/lib/librte_vhost/virtio_net.c
index 7f621fb..48b013a 100644 (file)
--- a/lib/librte_vhost/virtio_net.c
+++ b/lib/librte_vhost/virtio_net.c
@@ -812,9 +812,10 @@ copy_mbuf_to_desc(struct virtio_net *dev, struct vhost_virtqueue *vq,
 
        hdr_mbuf = m;
        hdr_addr = buf_addr;
-       if (unlikely(buf_len < dev->vhost_hlen))
+       if (unlikely(buf_len < dev->vhost_hlen)) {
+               memset(&tmp_hdr, 0, sizeof(struct virtio_net_hdr_mrg_rxbuf));
                hdr = &tmp_hdr;
-       else
+       } else
                hdr = (struct virtio_net_hdr_mrg_rxbuf *)(uintptr_t)hdr_addr;
 
        VHOST_LOG_DATA(DEBUG, "(%d) RX: num merge buffers %d\n",