arm: dma-mapping: limit IOMMU mapping size

arm_iommu_create_mapping() has size parameter of size_t and
arm_setup_iommu_dma_ops() can take a value higher than that
when this is called from the OF code.  So limit the size to
SIZE_MAX.

Tested-by: Suravee Suthikulpanit <Suravee.Suthikulpanit@amd.com> (AMD Seattle)
Signed-off-by: Murali Karicheri <m-karicheri2@ti.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Will Deacon <will.deacon@arm.com>
CC: Joerg Roedel <joro@8bytes.org>
CC: Grant Likely <grant.likely@linaro.org>
CC: Rob Herring <robh+dt@kernel.org>
CC: Russell King <linux@arm.linux.org.uk>
CC: Arnd Bergmann <arnd@arndb.de>

diff --git a/arch/arm/mm/dma-mapping.c b/arch/arm/mm/dma-mapping.c
index 170a116d1b298c1befb81efdeaee49735362fd26..fc81a388994a4a947351e0114e1c19a706021aec 100644 (file)
--- a/arch/arm/mm/dma-mapping.c
+++ b/arch/arm/mm/dma-mapping.c
@@ -2027,6 +2027,13 @@ static bool arm_setup_iommu_dma_ops(struct device *dev, u64 dma_base, u64 size,
        if (!iommu)
                return false;
 
+       /*
+        * currently arm_iommu_create_mapping() takes a max of size_t
+        * for size param. So check this limit for now.
+        */
+       if (size > SIZE_MAX)
+               return false;
+
        mapping = arm_iommu_create_mapping(dev->bus, dma_base, size);
        if (IS_ERR(mapping)) {
                pr_warn("Failed to create %llu-byte IOMMU mapping for device %s\n",