Virtualization - Mar 2022 - [PATCH v3] vsock: each transport cycles only on its own sockets

On Thu, Mar 10, 2022 at 10:50:11PM +0900, Jiyong Park
wrote:
>When iterating over sockets using vsock_for_each_connected_socket, make
>sure that a transport filters out sockets that don't belong to the
>transport.
>
>There actually was an issue caused by this; in a nested VM
>configuration, destroying the nested VM (which often involves the
>closing of /dev/vhost-vsock if there was h2g connections to the nested
>VM) kills not only the h2g connections, but also all existing g2h
>connections to the (outmost) host which are totally unrelated.
>
>Tested: Executed the following steps on Cuttlefish (Android running on a
>VM) [1]: (1) Enter into an `adb shell` session - to have a g2h
>connection inside the VM, (2) open and then close /dev/vhost-vsock by
>`exec 3< /dev/vhost-vsock && exec 3<&-`, (3) observe that
the adb
>session is not reset.
>
>[1] https://android.googlesource.com/device/google/cuttlefish/
>
>Fixes: c0cfa2d8a788 ("vsock: add multi-transports support")
>Signed-off-by: Jiyong Park <jiyong at google.com>
>---
>Changes in v3:
>  - Fixed the build error in vmci_transport.c
>Changes in v2:
>  - Squashed into a single patch
>
> drivers/vhost/vsock.c            | 3 ++-
> include/net/af_vsock.h           | 3 ++-
> net/vmw_vsock/af_vsock.c         | 9 +++++++--
> net/vmw_vsock/virtio_transport.c | 7 +++++--
> net/vmw_vsock/vmci_transport.c   | 5 ++++-
> 5 files changed, 20 insertions(+), 7 deletions(-)
It seems okay now, I ran my test suite and everything seems to be fine:

Reviewed-by: Stefano Garzarella <sgarzare at redhat.com>

Thanks,
Stefano

On Thu, Mar 10, 2022 at 03:14:20PM +0100, Stefano Garzarella
wrote:
> On Thu, Mar 10, 2022 at 10:50:11PM +0900, Jiyong Park wrote:
> > When iterating over sockets using vsock_for_each_connected_socket,
make
> > sure that a transport filters out sockets that don't belong to the
> > transport.
> > 
> > There actually was an issue caused by this; in a nested VM
> > configuration, destroying the nested VM (which often involves the
> > closing of /dev/vhost-vsock if there was h2g connections to the nested
> > VM) kills not only the h2g connections, but also all existing g2h
> > connections to the (outmost) host which are totally unrelated.
> > 
> > Tested: Executed the following steps on Cuttlefish (Android running on
a
> > VM) [1]: (1) Enter into an `adb shell` session - to have a g2h
> > connection inside the VM, (2) open and then close /dev/vhost-vsock by
> > `exec 3< /dev/vhost-vsock && exec 3<&-`, (3) observe
that the adb
> > session is not reset.
> > 
> > [1] https://android.googlesource.com/device/google/cuttlefish/
> > 
> > Fixes: c0cfa2d8a788 ("vsock: add multi-transports support")
> > Signed-off-by: Jiyong Park <jiyong at google.com>
> > ---
> > Changes in v3:
> >  - Fixed the build error in vmci_transport.c
> > Changes in v2:
> >  - Squashed into a single patch
> > 
> > drivers/vhost/vsock.c            | 3 ++-
> > include/net/af_vsock.h           | 3 ++-
> > net/vmw_vsock/af_vsock.c         | 9 +++++++--
> > net/vmw_vsock/virtio_transport.c | 7 +++++--
> > net/vmw_vsock/vmci_transport.c   | 5 ++++-
> > 5 files changed, 20 insertions(+), 7 deletions(-)
> 
> It seems okay now, I ran my test suite and everything seems to be fine:
> 
> Reviewed-by: Stefano Garzarella <sgarzare at redhat.com>
> 
> Thanks,
> Stefanoc
Thanks!
Acked-by: Michael S. Tsirkin <mst at redhat.com>

Not a new regression so I think we should take this in the next cycle,
let's be careful here especially since previous version was not even
build-tested by the contributor.

-- 
MST