4.4-stable review patch. If anyone has any objections, please let me know.
------------------ From: Jean-Philippe Brucker <[email protected]> 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 <[email protected]> Signed-off-by: Jean-Philippe Brucker <[email protected]> Signed-off-by: Will Deacon <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> --- 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)
