This is a note to let you know that I've just added the patch titled

iommu/arm-smmu-v3: Don't free page table ops twice

to the 4.4-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git%3Ba=su...

The filename of the patch is: iommu-arm-smmu-v3-don-t-free-page-table-ops-twice.patch and it can be found in the queue-4.4 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let stable@vger.kernel.org know about it.

From 57d72e159b60456c8bb281736c02ddd3164037aa 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: iommu/arm-smmu-v3: Don't free page table ops twice

From: Jean-Philippe Brucker jean-philippe.brucker@arm.com

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") Reviewed-by: Robin Murphy robin.murphy@arm.com Signed-off-by: Jean-Philippe Brucker jean-philippe.brucker@arm.com Signed-off-by: Will Deacon will.deacon@arm.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org

--- drivers/iommu/arm-smmu-v3.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-)

--- a/drivers/iommu/arm-smmu-v3.c +++ b/drivers/iommu/arm-smmu-v3.c @@ -1541,13 +1541,15 @@ static int arm_smmu_domain_finalise(stru 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)

Patches currently in stable-queue which might be from jean-philippe.brucker@arm.com are

queue-4.4/iommu-arm-smmu-v3-don-t-free-page-table-ops-twice.patch