vhost-net: Always access vq->private_data under vq mutex

Signed-off-by: Asias He <asias@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

diff --git a/drivers/vhost/net.c b/drivers/vhost/net.c
index 027be91..99f8d63 100644 (file)
--- a/drivers/vhost/net.c
+++ b/drivers/vhost/net.c
@@ -346,12 +346,11 @@ static void handle_tx(struct vhost_net *net)
        struct vhost_net_ubuf_ref *uninitialized_var(ubufs);
        bool zcopy, zcopy_used;
 
-       /* TODO: check that we are running from vhost_worker? */
-       sock = rcu_dereference_check(vq->private_data, 1);
+       mutex_lock(&vq->mutex);
+       sock = vq->private_data;
        if (!sock)
-               return;
+               goto out;
 
-       mutex_lock(&vq->mutex);
        vhost_disable_notify(&net->dev, vq);
 
        hdr_size = nvq->vhost_hlen;
@@ -461,7 +460,7 @@ static void handle_tx(struct vhost_net *net)
                        break;
                }
        }
-
+out:
        mutex_unlock(&vq->mutex);
 }
 
@@ -570,14 +569,14 @@ static void handle_rx(struct vhost_net *net)
        s16 headcount;
        size_t vhost_hlen, sock_hlen;
        size_t vhost_len, sock_len;
-       /* TODO: check that we are running from vhost_worker? */
-       struct socket *sock = rcu_dereference_check(vq->private_data, 1);
-
-       if (!sock)
-               return;
+       struct socket *sock;
 
        mutex_lock(&vq->mutex);
+       sock = vq->private_data;
+       if (!sock)
+               goto out;
        vhost_disable_notify(&net->dev, vq);
+
        vhost_hlen = nvq->vhost_hlen;
        sock_hlen = nvq->sock_hlen;
 
@@ -652,7 +651,7 @@ static void handle_rx(struct vhost_net *net)
                        break;
                }
        }
-
+out:
        mutex_unlock(&vq->mutex);
 }