Linux Virtualization - Dec 2014 - [PATCH net-next V2] virtio-net: don't do header check for dodgy gso packets

There's no need to do header check for virtio-net since:

- Host sets dodgy for all gso packets from guest and check the header.
- Host should be prepared for all kinds of evil packets from guest, since
  malicious guest can send any kinds of packet.

So this patch sets NETIF_F_GSO_ROBUST for virtio-net to skip the check.

Cc: Rusty Russell <rusty at rustcorp.com.au>
Cc: Michael S. Tsirkin <mst at redhat.com>
Acked-by: Michael S. Tsirkin <mst at redhat.com>
Signed-off-by: Jason Wang <jasowang at redhat.com>
---
Changes from V1:
- typo fixes
---
 drivers/net/virtio_net.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
index b8bd719..45c6ce2 100644
--- a/drivers/net/virtio_net.c
+++ b/drivers/net/virtio_net.c
@@ -1761,6 +1761,8 @@ static int virtnet_probe(struct virtio_device *vdev)
 		if (virtio_has_feature(vdev, VIRTIO_NET_F_HOST_ECN))
 			dev->hw_features |= NETIF_F_TSO_ECN;
 
+		dev->features |= NETIF_F_GSO_ROBUST;
+
 		if (gso)
 			dev->features |= dev->hw_features & NETIF_F_ALL_TSO;
 		/* (!csum && gso) case will be fixed by register_netdev() */
-- 
1.9.1

From: Jason Wang <jasowang at redhat.com>
Date: Wed, 24 Dec 2014 11:03:52 +0800
> There's no need to do header check for virtio-net since:
> 
> - Host sets dodgy for all gso packets from guest and check the header.
> - Host should be prepared for all kinds of evil packets from guest, since
>   malicious guest can send any kinds of packet.
> 
> So this patch sets NETIF_F_GSO_ROBUST for virtio-net to skip the check.
> 
> Cc: Rusty Russell <rusty at rustcorp.com.au>
> Cc: Michael S. Tsirkin <mst at redhat.com>
> Acked-by: Michael S. Tsirkin <mst at redhat.com>
> Signed-off-by: Jason Wang <jasowang at redhat.com>
> ---
> Changes from V1:
> - typo fixes
Applied.