From mboxrd@z Thu Jan 1 00:00:00 1970 From: will.deacon@arm.com (Will Deacon) Date: Fri, 15 Nov 2013 12:53:16 +0000 Subject: [PATCH -next] iommu/arm-smmu: fix potential NULL pointer dereference in arm_smmu_map() In-Reply-To: References: Message-ID: <20131115125315.GD19468@mudshark.cambridge.arm.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Fri, Nov 15, 2013 at 09:45:03AM +0000, Wei Yongjun wrote: > From: Wei Yongjun > > The dereference should be moved below the NULL test. > > Signed-off-by: Wei Yongjun > --- > drivers/iommu/arm-smmu.c | 3 +-- > 1 file changed, 1 insertion(+), 2 deletions(-) > > diff --git a/drivers/iommu/arm-smmu.c b/drivers/iommu/arm-smmu.c > index 2349d62..a0cc0a5 100644 > --- a/drivers/iommu/arm-smmu.c > +++ b/drivers/iommu/arm-smmu.c > @@ -1420,9 +1420,8 @@ static int arm_smmu_map(struct iommu_domain *domain, unsigned long iova, > phys_addr_t paddr, size_t size, int flags) > { > struct arm_smmu_domain *smmu_domain = domain->priv; > - struct arm_smmu_device *smmu = smmu_domain->leaf_smmu; > > - if (!smmu_domain || !smmu) > + if (!smmu_domain || !smmu_domain->leaf_smmu) > return -ENODEV; > > /* Check for silent address truncation up the SMMU chain. */ I already have a patch for this, but actually, we can remove that check altogether. I'll fix it in my tree. Will