[PATCH v4 4/5] iommu/s390: Fix incorrect aperture check

[Niklas Schnelle]

The domain->geometry.aperture_end specifies the last valid address treat
it as such when checking if a DMA address is valid.

Reviewed-by: Pierre Morel <pmorel@xxxxxxxxxxxxx>
Reviewed-by: Matthew Rosato <mjrosato@xxxxxxxxxxxxx>
Signed-off-by: Niklas Schnelle <schnelle@xxxxxxxxxxxxx>
---
v3 -> v4:
- Make aperture check resistant against overflow (Jason)

 drivers/iommu/s390-iommu.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/iommu/s390-iommu.c b/drivers/iommu/s390-iommu.c
index 762dc55aea1e..94c444b909bd 100644
--- a/drivers/iommu/s390-iommu.c
+++ b/drivers/iommu/s390-iommu.c
@@ -200,7 +200,7 @@ static int s390_iommu_update_trans(struct s390_domain *s390_domain,
 	int rc = 0;
 
 	if (dma_addr < s390_domain->domain.geometry.aperture_start ||
-	    dma_addr + size > s390_domain->domain.geometry.aperture_end)
+	    (dma_addr + size - 1) > s390_domain->domain.geometry.aperture_end)
 		return -EINVAL;
 
 	nr_pages = PAGE_ALIGN(size) >> PAGE_SHIFT;
-- 
2.34.1