On Thu, Mar 10, 2022 at 09:54:24PM +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@xxxxxxxxxx> > --- > drivers/vhost/vsock.c | 4 ++++ > net/vmw_vsock/virtio_transport.c | 7 +++++++ > net/vmw_vsock/vmci_transport.c | 5 +++++ > 3 files changed, 16 insertions(+) > > diff --git a/drivers/vhost/vsock.c b/drivers/vhost/vsock.c > index 37f0b4274113..853ddac00d5b 100644 > --- a/drivers/vhost/vsock.c > +++ b/drivers/vhost/vsock.c > @@ -722,6 +722,10 @@ static void vhost_vsock_reset_orphans(struct sock *sk) > * executing. > */ > > + /* Only handle our own sockets */ > + if (vsk->transport != &vhost_transport.transport) > + return; > + > /* If the peer is still valid, no need to reset connection */ > if (vhost_vsock_get(vsk->remote_addr.svm_cid)) > return; We know this is incomplete though. So I think it's the wrong thing to do when you backport, too. If all you worry about is breaking a binary module interface, how about simply exporting a new function when you backport. Thus you will have downstream both: void vsock_for_each_connected_socket(void (*fn)(struct sock *sk)); void vsock_for_each_connected_socket_new(struct vsock_transport *transport, void (*fn)(struct sock *sk)); and then upstream we can squash these two patches. Hmm? > diff --git a/net/vmw_vsock/virtio_transport.c b/net/vmw_vsock/virtio_transport.c > index fb3302fff627..61b24eb31d4b 100644 > --- a/net/vmw_vsock/virtio_transport.c > +++ b/net/vmw_vsock/virtio_transport.c > @@ -24,6 +24,7 @@ > static struct workqueue_struct *virtio_vsock_workqueue; > static struct virtio_vsock __rcu *the_virtio_vsock; > static DEFINE_MUTEX(the_virtio_vsock_mutex); /* protects the_virtio_vsock */ > +static struct virtio_transport virtio_transport; /* forward declaration */ > > struct virtio_vsock { > struct virtio_device *vdev; > @@ -357,11 +358,17 @@ static void virtio_vsock_event_fill(struct virtio_vsock *vsock) > > static void virtio_vsock_reset_sock(struct sock *sk) > { > + struct vsock_sock *vsk = vsock_sk(sk); > + > /* vmci_transport.c doesn't take sk_lock here either. At least we're > * under vsock_table_lock so the sock cannot disappear while we're > * executing. > */ > > + /* Only handle our own sockets */ > + if (vsk->transport != &virtio_transport.transport) > + return; > + > sk->sk_state = TCP_CLOSE; > sk->sk_err = ECONNRESET; > sk_error_report(sk); > diff --git a/net/vmw_vsock/vmci_transport.c b/net/vmw_vsock/vmci_transport.c > index 7aef34e32bdf..cd2f01513fae 100644 > --- a/net/vmw_vsock/vmci_transport.c > +++ b/net/vmw_vsock/vmci_transport.c > @@ -803,6 +803,11 @@ static void vmci_transport_handle_detach(struct sock *sk) > struct vsock_sock *vsk; > > vsk = vsock_sk(sk); > + > + /* Only handle our own sockets */ > + if (vsk->transport != &vmci_transport) > + return; > + > if (!vmci_handle_is_invalid(vmci_trans(vsk)->qp_handle)) { > sock_set_flag(sk, SOCK_DONE); > > -- > 2.35.1.723.g4982287a31-goog
