| Message ID | E1ZJhWe-00043f-KS@rmk-PC.arm.linux.org.uk (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
diff --git a/drivers/iommu/tegra-smmu.c b/drivers/iommu/tegra-smmu.c index c1f2e521dc52..083354903a1a 100644 --- a/drivers/iommu/tegra-smmu.c +++ b/drivers/iommu/tegra-smmu.c @@ -592,6 +592,9 @@ static phys_addr_t tegra_smmu_iova_to_phys(struct iommu_domain *domain, u32 *pte; pte = as_get_pte(as, iova, &page); + if (!pte || !*pte) + return 0; + pfn = *pte & as->smmu->pfn_mask; return PFN_PHYS(pfn);
iova_to_phys() has several problems: (a) iova_to_phys() is supposed to return 0 if there is no entry present for the iova. (b) if as_get_pte() fails, we oops the kernel by dereferencing a NULL pointer. Really, we should not even be trying to allocate a page table at all, but should only be returning the presence of the 2nd level page table. This will be fixed in a subsequent patch. Treat both of these conditions as "no mapping" conditions. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> --- drivers/iommu/tegra-smmu.c | 3 +++ 1 file changed, 3 insertions(+)