[dpdk-stable] [PATCH 2/2] vhost: fix async enqueue accessing uninitialized variables

[Xia, Chenbo]

> -----Original Message-----
> From: Liu, Yong <yong.liu at intel.com>
> Sent: Wednesday, April 7, 2021 11:25 AM
> To: maxime.coquelin at redhat.com; Xia, Chenbo <chenbo.xia at intel.com>
> Cc: dev at dpdk.org; Liu, Yong <yong.liu at intel.com>; stable at dpdk.org
> Subject: [PATCH 2/2] vhost: fix async enqueue accessing uninitialized
> variables
> 
> This patch fixs coverity issue in async enqueue function by adding
> initialization step before using temporary virtio header.
> 
> Coverity issue: 366123
> Fixes: cd6760da1076 ("vhost: introduce async enqueue for split ring")
> Cc: stable at dpdk.org
> 
> Signed-off-by: Marvin Liu <yong.liu at intel.com>
> 
> diff --git a/lib/librte_vhost/virtio_net.c b/lib/librte_vhost/virtio_net.c
> index 48b013a9b4..ff39878609 100644
> --- a/lib/librte_vhost/virtio_net.c
> +++ b/lib/librte_vhost/virtio_net.c
> @@ -986,9 +986,10 @@ async_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",
> --
> 2.17.1

Reviewed-by: Chenbo Xia <chenbo.xia at intel.com>