Re: [PATCH hyperv-next] Drivers: hv: vmbus: Copy packets sent by Hyper-V out of the ring buffer

[Wei Liu]

On Thu, Apr 08, 2021 at 06:14:39PM +0200, Andrea Parri (Microsoft) wrote:
> From: Andres Beltran <lkmlabelt@xxxxxxxxx>
> 
> Pointers to ring-buffer packets sent by Hyper-V are used within the
> guest VM. Hyper-V can send packets with erroneous values or modify
> packet fields after they are processed by the guest. To defend
> against these scenarios, return a copy of the incoming VMBus packet
> after validating its length and offset fields in hv_pkt_iter_first().
> In this way, the packet can no longer be modified by the host.
> 
> Signed-off-by: Andres Beltran <lkmlabelt@xxxxxxxxx>
> Co-developed-by: Andrea Parri (Microsoft) <parri.andrea@xxxxxxxxx>
> Signed-off-by: Andrea Parri (Microsoft) <parri.andrea@xxxxxxxxx>
> ---
>  drivers/hv/channel.c              |  9 ++--
>  drivers/hv/hv_fcopy.c             |  1 +
>  drivers/hv/hv_kvp.c               |  1 +
>  drivers/hv/hyperv_vmbus.h         |  2 +-
>  drivers/hv/ring_buffer.c          | 82 ++++++++++++++++++++++++++-----
>  drivers/net/hyperv/hyperv_net.h   |  7 +++
>  drivers/net/hyperv/netvsc.c       |  2 +
>  drivers/net/hyperv/rndis_filter.c |  2 +
>  drivers/scsi/storvsc_drv.c        | 10 ++++
>  include/linux/hyperv.h            | 48 +++++++++++++++---
>  net/vmw_vsock/hyperv_transport.c  |  4 +-
>  11 files changed, 143 insertions(+), 25 deletions(-)

In theory this patch needs acks from network and scsi maintainers, but
the changes are so small and specific to Hyper-V drivers. In the
interest of making progress, I will be picking up this patch shortly
unless I hear objections.


Wei.