The patch below does not apply to the 4.4-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <stable@xxxxxxxxxxxxxxx>. thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From 57d72e159b60456c8bb281736c02ddd3164037aa Mon Sep 17 00:00:00 2001 From: Jean-Philippe Brucker <jean-philippe.brucker@xxxxxxx> Date: Thu, 14 Dec 2017 11:03:01 +0000 Subject: [PATCH] iommu/arm-smmu-v3: Don't free page table ops twice Kasan reports a double free when finalise_stage_fn fails: the io_pgtable ops are freed by arm_smmu_domain_finalise and then again by arm_smmu_domain_free. Prevent this by leaving pgtbl_ops empty on failure. Cc: <stable@xxxxxxxxxxxxxxx> Fixes: 48ec83bcbcf5 ("iommu/arm-smmu: Add initial driver support for ARM SMMUv3 devices") Reviewed-by: Robin Murphy <robin.murphy@xxxxxxx> Signed-off-by: Jean-Philippe Brucker <jean-philippe.brucker@xxxxxxx> Signed-off-by: Will Deacon <will.deacon@xxxxxxx> diff --git a/drivers/iommu/arm-smmu-v3.c b/drivers/iommu/arm-smmu-v3.c index f122071688fd..db4281d0e269 100644 --- a/drivers/iommu/arm-smmu-v3.c +++ b/drivers/iommu/arm-smmu-v3.c @@ -1698,13 +1698,15 @@ static int arm_smmu_domain_finalise(struct iommu_domain *domain) domain->pgsize_bitmap = pgtbl_cfg.pgsize_bitmap; domain->geometry.aperture_end = (1UL << ias) - 1; domain->geometry.force_aperture = true; - smmu_domain->pgtbl_ops = pgtbl_ops; ret = finalise_stage_fn(smmu_domain, &pgtbl_cfg); - if (ret < 0) + if (ret < 0) { free_io_pgtable_ops(pgtbl_ops); + return ret; + } - return ret; + smmu_domain->pgtbl_ops = pgtbl_ops; + return 0; } static __le64 *arm_smmu_get_step_for_sid(struct arm_smmu_device *smmu, u32 sid)