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>
Cc: "David S. Miller" <da...@davemloft.net>
Cc: Jakub Kicinski <k...@kernel.org>
Cc: net...@vger.kernel.org
---
drivers/net/hyperv/netvsc.c | 27 ++++++++++++++++++++++++---
1 file changed, 24 insertions(+), 3 deletions(-)
diff --git a/drivers/net/hyperv/netvsc.c b/drivers/net/hyperv/netvsc.c
index 1510a236aa341..afd92b4aa21fe 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())
+
init_packet->msg.v2_msg.send_ndis_config.capability.sriov = 1;
+ else
+ netdev_info(ndev, "SR-IOV not advertised by guests on
the host supporting isolation\n");
/* Teaming bit is needed to receive link speed updates */
init_packet->msg.v2_msg.send_ndis_config.capability.teaming = 1;
@@ -563,6 +567,13 @@ static int negotiate_nvsp_ver(struct hv_device *device,
return ret;
}
+static bool nvsp_is_valid_version(u32 version)
+{
+ if (hv_is_isolation_supported())
+ return version >= NVSP_PROTOCOL_VERSION_61;
+ return true;
+}
+
static int netvsc_connect_vsp(struct hv_device *device,
struct netvsc_device *net_device,
const struct netvsc_device_info *device_info)
@@ -579,12 +590,19 @@ static int netvsc_connect_vsp(struct hv_device *device,
init_packet = &net_device->channel_init_pkt;
/* Negotiate the latest NVSP protocol supported */
- for (i = ARRAY_SIZE(ver_list) - 1; i >= 0; i--)
+ for (i = ARRAY_SIZE(ver_list) - 1; i >= 0; i--) {
if (negotiate_nvsp_ver(device, net_device, init_packet,
ver_list[i]) == 0) {
+ if (!nvsp_is_valid_version(ver_list[i])) {
+ netdev_err(ndev, "Invalid NVSP version 0x%x
(expected >= 0x%x) from the host with isolation supported\n",
+ ver_list[i],
NVSP_PROTOCOL_VERSION_61);
+ ret = -EPROTO;
+ goto cleanup;
+ }
net_device->nvsp_version = ver_list[i];
break;
}
+ }
if (i < 0) {
ret = -EPROTO;
@@ -1357,7 +1375,10 @@ 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())
+ netvsc_send_vf(ndev, nvmsg, msglen);
+ else
+ netdev_err(ndev, "Ignore VF_ASSOCIATION msg from the
host supporting isolation\n");
break;
}
}
--
2.25.1
