1 files changed, 19 insertions, 6 deletions

diff --git a/drivers/vhost/net.c b/drivers/vhost/net.c
index df5b6b971f26..d219070fed3d 100644
--- a/drivers/vhost/net.c
+++ b/drivers/vhost/net.c
@@ -98,7 +98,8 @@ static void tx_poll_start(struct vhost_net *net, struct socket *sock)
 static void handle_tx(struct vhost_net *net)
 {
         struct vhost_virtqueue *vq = &net->dev.vqs[VHOST_NET_VQ_TX];
-        unsigned head, out, in, s;
+        unsigned out, in, s;
+        int head;
         struct msghdr msg = {
                 .msg_name = NULL,
                 .msg_namelen = 0,
@@ -135,6 +136,9 @@ static void handle_tx(struct vhost_net *net)
                                          ARRAY_SIZE(vq->iov),
                                          &out, &in,
                                          NULL, NULL);
+                /* On error, stop handling until the next kick. */
+                if (unlikely(head < 0))
+                        break;
                 /* Nothing new?  Wait for eventfd to tell us they refilled. */
                 if (head == vq->num) {
                         wmem = atomic_read(&sock->sk->sk_wmem_alloc);
@@ -173,8 +177,8 @@ static void handle_tx(struct vhost_net *net)
                         break;
                 }
                 if (err != len)
-                        pr_err("Truncated TX packet: "
-                               " len %d != %zd\n", err, len);
+                        pr_debug("Truncated TX packet: "
+                                 " len %d != %zd\n", err, len);
                 vhost_add_used_and_signal(&net->dev, vq, head, 0);
                 total_len += len;
                 if (unlikely(total_len >= VHOST_NET_WEIGHT)) {
@@ -192,7 +196,8 @@ static void handle_tx(struct vhost_net *net)
 static void handle_rx(struct vhost_net *net)
 {
         struct vhost_virtqueue *vq = &net->dev.vqs[VHOST_NET_VQ_RX];
-        unsigned head, out, in, log, s;
+        unsigned out, in, log, s;
+        int head;
         struct vhost_log *vq_log;
         struct msghdr msg = {
                 .msg_name = NULL,
@@ -228,6 +233,9 @@ static void handle_rx(struct vhost_net *net)
                                          ARRAY_SIZE(vq->iov),
                                          &out, &in,
                                          vq_log, &log);
+                /* On error, stop handling until the next kick. */
+                if (unlikely(head < 0))
+                        break;
                 /* OK, now we need to know about added descriptors. */
                 if (head == vq->num) {
                         if (unlikely(vhost_enable_notify(vq))) {
@@ -267,8 +275,8 @@ static void handle_rx(struct vhost_net *net)
                 }
                 /* TODO: Should check and handle checksum. */
                 if (err > len) {
-                        pr_err("Discarded truncated rx packet: "
-                               " len %d > %zd\n", err, len);
+                        pr_debug("Discarded truncated rx packet: "
+                                 " len %d > %zd\n", err, len);
                         vhost_discard_vq_desc(vq);
                         continue;
                 }
@@ -526,11 +534,16 @@ static long vhost_net_set_backend(struct vhost_net *n, unsigned index, int fd)
         rcu_assign_pointer(vq->private_data, sock);
         vhost_net_enable_vq(n, vq);
 done:
+        mutex_unlock(&vq->mutex);
+
         if (oldsock) {
                 vhost_net_flush_vq(n, index);
                 fput(oldsock->file);
         }
 
+        mutex_unlock(&n->dev.mutex);
+        return 0;
+
 err_vq:
         mutex_unlock(&vq->mutex);
 err: