2022-10-04 12:17:13

by Niklas Schnelle

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

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 <[email protected]>
Reviewed-by: Matthew Rosato <[email protected]>
Signed-off-by: Niklas Schnelle <[email protected]>
---
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