From mboxrd@z Thu Jan 1 00:00:00 1970 From: Dan Carpenter Date: Fri, 25 Nov 2016 11:01:32 +0000 Subject: [patch] sparc64: move dereference after check for NULL Message-Id: <20161125105853.GB5938@mwanda> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: kernel-janitors@vger.kernel.org We shouldn't dereference "iommu" until after we have checked that it is non-NULL. Fixes: f08978b0fdbf ("sparc64: Enable sun4v dma ops to use IOMMU v2 APIs") Signed-off-by: Dan Carpenter --- Applies to sparc.git diff --git a/arch/sparc/kernel/pci_sun4v.c b/arch/sparc/kernel/pci_sun4v.c index 06981cc7..cabb609 100644 --- a/arch/sparc/kernel/pci_sun4v.c +++ b/arch/sparc/kernel/pci_sun4v.c @@ -478,11 +478,10 @@ static int dma_4v_map_sg(struct device *dev, struct scatterlist *sglist, BUG_ON(direction = DMA_NONE); iommu = dev->archdata.iommu; - atu = iommu->atu; - if (nelems = 0 || !iommu) return 0; - + atu = iommu->atu; + prot = HV_PCI_MAP_ATTR_READ; if (direction != DMA_TO_DEVICE) prot |= HV_PCI_MAP_ATTR_WRITE;