vfio: avoid possible overflow in vfio_iommu_type1_pin_pages

commit 0ea971f8 upstream.

add parentheses to avoid possible vaddr overflow.

Fixes: a54eb550 ("vfio iommu type1: Add support for mediated devices")
Signed-off-by: NYan Zhao <yan.y.zhao@intel.com>
Signed-off-by: NAlex Williamson <alex.williamson@redhat.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: NYang Yingliang <yangyingliang@huawei.com>

drivers/vfio/vfio_iommu_type1.c

@@ -602,7 +602,7 @@ static int vfio_iommu_type1_pin_pages(void *iommu_data,
 			continue;
 		}
 
-		remote_vaddr = dma->vaddr + iova - dma->iova;
+		remote_vaddr = dma->vaddr + (iova - dma->iova);
 		ret = vfio_pin_page_external(dma, remote_vaddr, &phys_pfn[i],
 					     do_accounting);
 		if (ret)