From: Andrea Parri (Microsoft) <parri.and...@gmail.com> Sent: Monday, February
1, 2021 6:48 AM
>
> Restrict the NVSP protocol version(s) that will be negotiated with the
> host to be NVSP_PROTOCOL_VERSION_61 or greater if the guest is running
> isolated. Moreover, do not advertise the SR-IOV capability and ignore
> NVSP_MSG_4_TYPE_SEND_VF_ASSOCIATION messages in isolated guests, which
> are not supposed to support SR-IOV. This reduces the footprint of the
> code that will be exercised by Confidential VMs and hence the exposure
> to bugs and vulnerabilities.
>
> Signed-off-by: Andrea Parri (Microsoft) <parri.and...@gmail.com>
> Acked-by: Jakub Kicinski <k...@kernel.org>
> Reviewed-by: Haiyang Zhang <haiya...@microsoft.com>
> Cc: "David S. Miller" <da...@davemloft.net>
> Cc: Jakub Kicinski <k...@kernel.org>
> Cc: net...@vger.kernel.org
> ---
> drivers/net/hyperv/netvsc.c | 18 ++++++++++++++++--
> 1 file changed, 16 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/net/hyperv/netvsc.c b/drivers/net/hyperv/netvsc.c
> index 1510a236aa341..51005f2d4a821 100644
> --- a/drivers/net/hyperv/netvsc.c
> +++ b/drivers/net/hyperv/netvsc.c
> @@ -22,6 +22,7 @@
> #include <linux/prefetch.h>
>
> #include <asm/sync_bitops.h>
> +#include <asm/mshyperv.h>
>
> #include "hyperv_net.h"
> #include "netvsc_trace.h"
> @@ -544,7 +545,10 @@ static int negotiate_nvsp_ver(struct hv_device *device,
> init_packet->msg.v2_msg.send_ndis_config.capability.ieee8021q = 1;
>
> if (nvsp_ver >= NVSP_PROTOCOL_VERSION_5) {
> - init_packet->msg.v2_msg.send_ndis_config.capability.sriov = 1;
> + if (hv_is_isolation_supported())
> + netdev_info(ndev, "SR-IOV not advertised by guests on
> the host supporting isolation\n");
> + else
> +
> init_packet->msg.v2_msg.send_ndis_config.capability.sriov = 1;
>
> /* Teaming bit is needed to receive link speed updates */
> init_packet->msg.v2_msg.send_ndis_config.capability.teaming = 1;
> @@ -591,6 +595,13 @@ static int netvsc_connect_vsp(struct hv_device *device,
> goto cleanup;
> }
>
> + if (hv_is_isolation_supported() && net_device->nvsp_version <
> NVSP_PROTOCOL_VERSION_61) {
> + netdev_err(ndev, "Invalid NVSP version 0x%x (expected >= 0x%x)
> from the host supporting isolation\n",
> + net_device->nvsp_version, NVSP_PROTOCOL_VERSION_61);
> + ret = -EPROTO;
> + goto cleanup;
> + }
> +
> pr_debug("Negotiated NVSP version:%x\n", net_device->nvsp_version);
>
> /* Send the ndis version */
> @@ -1357,7 +1368,10 @@ static void netvsc_receive_inband(struct net_device
> *ndev,
> break;
>
> case NVSP_MSG4_TYPE_SEND_VF_ASSOCIATION:
> - netvsc_send_vf(ndev, nvmsg, msglen);
> + if (hv_is_isolation_supported())
> + netdev_err(ndev, "Ignore VF_ASSOCIATION msg from the
> host supporting isolation\n");
> + else
> + netvsc_send_vf(ndev, nvmsg, msglen);
> break;
> }
> }
> --
> 2.25.1
Reviewed-by: Michael Kelley <mikel...@microsoft.com>
