Hi,
On Sun, Jan 07, 2018 at 08:35:02AM +0000, gregkh@linuxfoundation.org wrote:
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@vger.kernel.org.
Please consider applying the updated backport for 4.4-stable, below.
Thanks, Jean
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From 36a792dfdaff7fafeb7b870cc0f86a339df9ea25 Mon Sep 17 00:00:00 2001
From: Jean-Philippe Brucker jean-philippe.brucker@arm.com Date: Thu, 14 Dec 2017 11:03:01 +0000 Subject: [PATCH] iommu/arm-smmu-v3: Don't free page table ops twice
commit 57d72e159b60456c8bb281736c02ddd3164037aa upstream.
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.
Fixes: 48ec83bcbcf5 ("iommu/arm-smmu: Add initial driver support for ARM SMMUv3 devices") Signed-off-by: Jean-Philippe Brucker jean-philippe.brucker@arm.com --- drivers/iommu/arm-smmu-v3.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-)
diff --git a/drivers/iommu/arm-smmu-v3.c b/drivers/iommu/arm-smmu-v3.c index 64f1eb8fdcbc..347aaaa5a7ea 100644 --- a/drivers/iommu/arm-smmu-v3.c +++ b/drivers/iommu/arm-smmu-v3.c @@ -1541,13 +1541,15 @@ static int arm_smmu_domain_finalise(struct iommu_domain *domain) return -ENOMEM;
arm_smmu_ops.pgsize_bitmap = pgtbl_cfg.pgsize_bitmap; - smmu_domain->pgtbl_ops = pgtbl_ops;
ret = finalise_stage_fn(smmu_domain, &pgtbl_cfg); - if (IS_ERR_VALUE(ret)) + if (IS_ERR_VALUE(ret)) { free_io_pgtable_ops(pgtbl_ops); + return ret; + }
- return ret; + smmu_domain->pgtbl_ops = pgtbl_ops; + return 0; }
static struct arm_smmu_group *arm_smmu_group_get(struct device *dev) -- 2.15.1