From: Breno Leitao <leitao@xxxxxxxxxx>
[ Upstream commit 984ecdd68de0fa1f63ce205d6c19ef5a7bc67b40 ]
The tbl pointer is being derefenced by IOMMU_PAGE_SIZE prior the check
if it is not NULL.
Just moving the dereference code to after the check, where there will
be guarantee that 'tbl' will not be NULL.
Signed-off-by: Breno Leitao <leitao@xxxxxxxxxx>
Signed-off-by: Michael Ellerman <mpe@xxxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
arch/powerpc/kernel/iommu.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/arch/powerpc/kernel/iommu.c b/arch/powerpc/kernel/iommu.c
index 19b4c628f3bec..f0dc680e659af 100644
--- a/arch/powerpc/kernel/iommu.c
+++ b/arch/powerpc/kernel/iommu.c
@@ -785,9 +785,9 @@ dma_addr_t iommu_map_page(struct device *dev, struct iommu_table *tbl,
vaddr = page_address(page) + offset;
uaddr = (unsigned long)vaddr;
- npages = iommu_num_pages(uaddr, size, IOMMU_PAGE_SIZE(tbl));
if (tbl) {
+ npages = iommu_num_pages(uaddr, size, IOMMU_PAGE_SIZE(tbl));
align = 0;
if (tbl->it_page_shift < PAGE_SHIFT && size >= PAGE_SIZE &&
((unsigned long)vaddr & ~PAGE_MASK) == 0)
--
2.20.1
