vdpa: Protect vdpa reset with cf_mutex

Call reset using the wrapper function vdpa_reset() to make sure the
operation is serialized with cf_mutex.

This comes to protect from the following possible scenario:

vhost_vdpa_set_status() could call the reset op. Since the call is not
protected by cf_mutex, a netlink thread calling vdpa_dev_config_fill
could get passed the VIRTIO_CONFIG_S_FEATURES_OK check in
vdpa_dev_config_fill() and end up reporting wrong features.

Fixes: 5f6e85953d8f ("vdpa: Read device configuration only if FEATURES_OK")
Signed-off-by: Eli Cohen <elic@nvidia.com>
Link: https://lore.kernel.org/r/20220111183400.38418-3-elic@nvidia.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Si-Wei Liu<si-wei.liu@oracle.com>
Acked-by: Jason Wang <jasowang@redhat.com>

diff --git a/drivers/vhost/vdpa.c b/drivers/vhost/vdpa.c
index 0ed6cba..8515398 100644 (file)
--- a/drivers/vhost/vdpa.c
+++ b/drivers/vhost/vdpa.c
@@ -178,7 +178,7 @@ static long vhost_vdpa_set_status(struct vhost_vdpa *v, u8 __user *statusp)
                        vhost_vdpa_unsetup_vq_irq(v, i);
 
        if (status == 0) {
-               ret = ops->reset(vdpa);
+               ret = vdpa_reset(vdpa);
                if (ret)
                        return ret;
        } else