From: Xie Yongji <xieyongji@xxxxxxxxxxxxx> commit a9d064524fc3cf463b3bb14fa63de78aafb40dab upstream. Protect vhost device iotlb by vhost_dev->mutex. Otherwise, it might cause corruption of the list and interval tree in struct vhost_iotlb if userspace sends the VHOST_IOTLB_MSG_V2 message concurrently. Fixes: 4c8cf318("vhost: introduce vDPA-based backend") Cc: stable@xxxxxxxxxxxxxxx Signed-off-by: Xie Yongji <xieyongji@xxxxxxxxxxxxx> Acked-by: Jason Wang <jasowang@xxxxxxxxxx> Reviewed-by: Stefano Garzarella <sgarzare@xxxxxxxxxx> Link: https://lore.kernel.org/r/20210412095512.178-1-xieyongji@xxxxxxxxxxxxx Signed-off-by: Michael S. Tsirkin <mst@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/vhost/vdpa.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) --- a/drivers/vhost/vdpa.c +++ b/drivers/vhost/vdpa.c @@ -745,9 +745,11 @@ static int vhost_vdpa_process_iotlb_msg( const struct vdpa_config_ops *ops = vdpa->config; int r = 0; + mutex_lock(&dev->mutex); + r = vhost_dev_check_owner(dev); if (r) - return r; + goto unlock; switch (msg->type) { case VHOST_IOTLB_UPDATE: @@ -768,6 +770,8 @@ static int vhost_vdpa_process_iotlb_msg( r = -EINVAL; break; } +unlock: + mutex_unlock(&dev->mutex); return r; }