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
