Re: [RFC PATCH] virtio-net: introduce a new macaddr control

Stefan Hajnoczi
2013-01-11T09:50:17Z

On Thu, Jan 10, 2013 at 10:51:57PM +0800, akong@redhat.com wrote:
> @@ -349,6 +351,13 @@ static int virtio_net_handle_mac(VirtIONet *n, uint8_t cmd,
> {
> struct virtio_net_ctrl_mac mac_data;
>
> + if (cmd == VIRTIO_NET_CTRL_MAC_ADDR_SET && elem->out_num == 2) {
> + /* Set MAC address */
> + memcpy(n->mac, elem->out_sg[1].iov_base, elem->out_sg[1].iov_len);

We cannot trust the guest's iov_len, it could overflow n->mac.