Merge tag 'iommu-fixes-v4.13-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git...

Pull IOMMU fix from Joerg Roedel:
 "Fix a NULL-pointer dereference in arm_smmu_add_device"

* tag 'iommu-fixes-v4.13-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu:
  iommu/arm-smmu: fix null-pointer dereference in arm_smmu_add_device

diff --git a/drivers/iommu/arm-smmu.c b/drivers/iommu/arm-smmu.c
index b97188acc4f1006185a5f8cb4fb3ee0e5cf735cf..2d80fa8a0634aba34b366609d8bcc50f432bb31c 100644 (file)
--- a/drivers/iommu/arm-smmu.c
+++ b/drivers/iommu/arm-smmu.c
@@ -1519,6 +1519,13 @@ static int arm_smmu_add_device(struct device *dev)
 
        if (using_legacy_binding) {
                ret = arm_smmu_register_legacy_master(dev, &smmu);
+
+               /*
+                * If dev->iommu_fwspec is initally NULL, arm_smmu_register_legacy_master()
+                * will allocate/initialise a new one. Thus we need to update fwspec for
+                * later use.
+                */
+               fwspec = dev->iommu_fwspec;
                if (ret)
                        goto out_free;
        } else if (fwspec && fwspec->ops == &arm_smmu_ops) {