4.9-stable review patch. If anyone has any objections, please let me know.
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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 @@ -1547,13 +1547,15 @@ static int arm_smmu_domain_finalise(stru 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)