Re: [PATCH] vhost_net: initialize rx_ring in vhost_net_open()

[Eric Dumazet <eric.dumazet@gmail.com>]

On 03/08/2018 05:37 AM, Alexander Potapenko wrote:
> KMSAN reported a use of uninit memory in vhost_net_buf_unproduce()
> while trying to access n->vqs[VHOST_NET_VQ_TX].rx_ring:
> 
> 
> ==================================================================
> 
> Signed-off-by: Alexander Potapenko <glider@google.com>

Please identify bug origin with a Fixes: tag

This will tremendously help stable teams that are struggling with many 
backports these days.

Thanks.

> ---
>   drivers/vhost/net.c | 1 +
>   1 file changed, 1 insertion(+)
> 
> diff --git a/drivers/vhost/net.c b/drivers/vhost/net.c
> index 610cba276d47..60f1080bffc7 100644
> --- a/drivers/vhost/net.c
> +++ b/drivers/vhost/net.c
> @@ -948,6 +948,7 @@ static int vhost_net_open(struct inode *inode, struct file *f)
>   		n->vqs[i].done_idx = 0;
>   		n->vqs[i].vhost_hlen = 0;
>   		n->vqs[i].sock_hlen = 0;
> +		n->vqs[i].rx_ring = NULL;
>   		vhost_net_buf_init(&n->vqs[i].rxq);
>   	}
>   	vhost_dev_init(dev, vqs, VHOST_NET_VQ_MAX);
>