Merge tag 'iommu-fixes-v4.13-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu
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 b97188a..2d80fa8 100644
--- 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) {
