[PATCH 4.9 090/108] vhost/vsock: handle vhost_vq_init_access() error

From: Greg Kroah-Hartman
Date: Thu Jun 15 2017 - 14:07:44 EST


4.9-stable review patch. If anyone has any objections, please let me know.

------------------

From: Stefan Hajnoczi <stefanha@xxxxxxxxxx>


[ Upstream commit 0516ffd88fa0d006ee80389ce14a9ca5ae45e845 ]

Propagate the error when vhost_vq_init_access() fails and set
vq->private_data to NULL.

Signed-off-by: Stefan Hajnoczi <stefanha@xxxxxxxxxx>
Signed-off-by: Michael S. Tsirkin <mst@xxxxxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/vhost/vsock.c | 13 +++++++++----
1 file changed, 9 insertions(+), 4 deletions(-)

--- a/drivers/vhost/vsock.c
+++ b/drivers/vhost/vsock.c
@@ -368,6 +368,7 @@ static void vhost_vsock_handle_rx_kick(s

static int vhost_vsock_start(struct vhost_vsock *vsock)
{
+ struct vhost_virtqueue *vq;
size_t i;
int ret;

@@ -378,19 +379,20 @@ static int vhost_vsock_start(struct vhos
goto err;

for (i = 0; i < ARRAY_SIZE(vsock->vqs); i++) {
- struct vhost_virtqueue *vq = &vsock->vqs[i];
+ vq = &vsock->vqs[i];

mutex_lock(&vq->mutex);

if (!vhost_vq_access_ok(vq)) {
ret = -EFAULT;
- mutex_unlock(&vq->mutex);
goto err_vq;
}

if (!vq->private_data) {
vq->private_data = vsock;
- vhost_vq_init_access(vq);
+ ret = vhost_vq_init_access(vq);
+ if (ret)
+ goto err_vq;
}

mutex_unlock(&vq->mutex);
@@ -400,8 +402,11 @@ static int vhost_vsock_start(struct vhos
return 0;

err_vq:
+ vq->private_data = NULL;
+ mutex_unlock(&vq->mutex);
+
for (i = 0; i < ARRAY_SIZE(vsock->vqs); i++) {
- struct vhost_virtqueue *vq = &vsock->vqs[i];
+ vq = &vsock->vqs[i];

mutex_lock(&vq->mutex);
vq->private_data = NULL;