VMCI transport provides both g2h and h2g behaviors in a single
transport.
We are able to set (or not) the g2h behavior, detecting if we
are in a VMware guest (or not), but the h2g feature is always set.
This prevents to load other h2g transports while we are in a
VMware guest.
This patch adds a new 'transport_hg' to handle this case, reducing
the priority of transports that provide both g2h and h2g
behaviors. A transport that has g2h and h2g features, can be
bypassed by a transport that has only the h2g feature.
Signed-off-by: Stefano Garzarella <sgarzare@xxxxxxxxxx>
---
net/vmw_vsock/af_vsock.c | 29 ++++++++++++++++++++++++-----
1 file changed, 24 insertions(+), 5 deletions(-)
diff --git a/net/vmw_vsock/af_vsock.c b/net/vmw_vsock/af_vsock.c
index c52203fe52c4..c5f46b8242ce 100644
--- a/net/vmw_vsock/af_vsock.c
+++ b/net/vmw_vsock/af_vsock.c
@@ -134,6 +134,8 @@ static struct proto vsock_proto = {
static const struct vsock_transport *transport_h2g;
/* Transport used for guest->host communication */
static const struct vsock_transport *transport_g2h;
+/* Transport used for both host->guest and guest->host communication */
+static const struct vsock_transport *transport_hg;
/* Transport used for DGRAM communication */
static const struct vsock_transport *transport_dgram;
static DEFINE_MUTEX(vsock_register_mutex);
@@ -402,10 +404,13 @@ int vsock_assign_transport(struct vsock_sock *vsk, struct vsock_sock *psk)
vsk->transport = transport_dgram;
break;
case SOCK_STREAM:
- if (vsk->remote_addr.svm_cid > VMADDR_CID_HOST)
+ if (vsk->remote_addr.svm_cid > VMADDR_CID_HOST) {
vsk->transport = transport_h2g;
- else
+ if (!vsk->transport)
+ vsk->transport = transport_hg;
+ } else {
vsk->transport = transport_g2h;
+ }
break;
default:
return -ESOCKTNOSUPPORT;
@@ -423,7 +428,7 @@ static bool vsock_find_cid(unsigned int cid)
if (transport_g2h && cid == transport_g2h->get_local_cid())
return true;
- if (transport_h2g && cid == VMADDR_CID_HOST)
+ if ((transport_h2g || transport_hg) && cid == VMADDR_CID_HOST)
return true;
return false;
@@ -1997,6 +2002,8 @@ static long vsock_dev_do_ioctl(struct file *filp,
cid = transport_g2h->get_local_cid();
else if (transport_h2g)
cid = transport_h2g->get_local_cid();
+ else if (transport_hg)
+ cid = transport_hg->get_local_cid();
if (put_user(cid, p) != 0)
retval = -EFAULT;
@@ -2093,13 +2100,14 @@ EXPORT_SYMBOL_GPL(vsock_core_get_transport);
int vsock_core_register(const struct vsock_transport *t)
{
- const struct vsock_transport *t_h2g, *t_g2h, *t_dgram;
+ const struct vsock_transport *t_h2g, *t_hg, *t_g2h, *t_dgram;
int err = mutex_lock_interruptible(&vsock_register_mutex);
if (err)
return err;
t_h2g = transport_h2g;
+ t_hg = transport_hg;
t_g2h = transport_g2h;
t_dgram = transport_dgram;
@@ -2107,7 +2115,14 @@ int vsock_core_register(const struct vsock_transport *t)
* same transport. We are able to set the G2H feature only if we are
* in a VMware guest, but we are not able to do the same for the host.
*/
- if (t->features & VSOCK_TRANSPORT_F_H2G) {
+ if ((t->features & VSOCK_TRANSPORT_F_H2G) &&
+ (t->features & VSOCK_TRANSPORT_F_G2H)) {
+ if (t_hg) {
+ err = -EBUSY;
+ goto err_busy;
+ }
+ t_hg = t;
+ } else if (t->features & VSOCK_TRANSPORT_F_H2G) {
if (t_h2g) {
err = -EBUSY;
goto err_busy;
@@ -2132,6 +2147,7 @@ int vsock_core_register(const struct vsock_transport *t)
}
transport_h2g = t_h2g;
+ transport_hg = t_hg;
transport_g2h = t_g2h;
transport_dgram = t_dgram;
@@ -2151,6 +2167,9 @@ void vsock_core_unregister(const struct vsock_transport *t)
if (transport_h2g == t)
transport_h2g = NULL;
+ if (transport_hg == t)
+ transport_hg = NULL;
+
if (transport_g2h == t)
transport_g2h = NULL;
--
2.21.0
