Currently, during arm smmu probe, struct arm_smmu_device pointer is allocated. The pointer is reallocated to a new struct qcom_smmu in qcom_smmu_create() with devm_krealloc() which frees the smmu device after copying the data into the new pointer. The freed pointer is then passed again in devm_of_platform_populate() inside qcom_smmu_create() which causes a use-after-free issue. Fix the use-after-free issue by reassigning the old pointer to the new pointer where the struct was copied by devm_krealloc(). Signed-off-by: Pratyush Brahma <quic_pbrahma@xxxxxxxxxxx> --- drivers/iommu/arm/arm-smmu/arm-smmu-qcom.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/iommu/arm/arm-smmu/arm-smmu-qcom.c b/drivers/iommu/arm/arm-smmu/arm-smmu-qcom.c index ed5ed5da7740..49eaeed6a91c 100644 --- a/drivers/iommu/arm/arm-smmu/arm-smmu-qcom.c +++ b/drivers/iommu/arm/arm-smmu/arm-smmu-qcom.c @@ -710,6 +710,7 @@ static struct arm_smmu_device *qcom_smmu_create(struct arm_smmu_device *smmu, qsmmu = devm_krealloc(smmu->dev, smmu, sizeof(*qsmmu), GFP_KERNEL); if (!qsmmu) return ERR_PTR(-ENOMEM); + smmu = &qsmmu->smmu; qsmmu->smmu.impl = impl; qsmmu->data = data; @@ -719,7 +720,7 @@ static struct arm_smmu_device *qcom_smmu_create(struct arm_smmu_device *smmu, if (ret) return ERR_PTR(ret); - return &qsmmu->smmu; + return smmu; } /* Implementation Defined Register Space 0 register offsets */ -- 2.17.1
