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>

1 files changed, 10 insertions, 11 deletions

diff --git a/drivers/vhost/net.c b/drivers/vhost/net.c
index 027be91db139..99f8d63491aa 100644
--- 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);
 }