[PATCH 4.14 18/26] vfio: avoid possible overflow in vfio_iommu_type1_pin_pages

[Greg Kroah-Hartman]

From: Yan Zhao <yan.y.zhao@xxxxxxxxx>

commit 0ea971f8dcd6dee78a9a30ea70227cf305f11ff7 upstream.

add parentheses to avoid possible vaddr overflow.

Fixes: a54eb55045ae ("vfio iommu type1: Add support for mediated devices")
Signed-off-by: Yan Zhao <yan.y.zhao@xxxxxxxxx>
Signed-off-by: Alex Williamson <alex.williamson@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
 drivers/vfio/vfio_iommu_type1.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/drivers/vfio/vfio_iommu_type1.c
+++ b/drivers/vfio/vfio_iommu_type1.c
@@ -591,7 +591,7 @@ static int vfio_iommu_type1_pin_pages(vo
 			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)