[PATCH 1/2] iommu/omap: Check for valid archdata in attach_dev

[Suman Anna <s-anna-l0cyMroinI0@public.gmane.org>]

Any device requiring to be attached to an iommu_domain must have
valid archdata containing the necessary iommu information, which
is SoC-specific. Add a check in the omap_iommu_attach_dev to make
sure that the device has non-NULL archdata before accessing
different SoC-specific fields of the archdata. This prevents a
NULL pointer dereference on any misconfigured devices.

Signed-off-by: Suman Anna <s-anna-l0cyMroinI0@public.gmane.org>
---
 drivers/iommu/omap-iommu.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/drivers/iommu/omap-iommu.c b/drivers/iommu/omap-iommu.c
index 02ef0ac..f245d51 100644
--- a/drivers/iommu/omap-iommu.c
+++ b/drivers/iommu/omap-iommu.c
@@ -1092,6 +1092,12 @@ omap_iommu_attach_dev(struct iommu_domain *domain, struct device *dev)
 
 	spin_lock(&omap_domain->lock);
 
+	if (!arch_data) {
+		dev_err(dev, "device doesn't have an associated iommu\n");
+		ret = -EINVAL;
+		goto out;
+	}
+
 	/* only a single device is supported per domain for now */
 	if (omap_domain->iommu_dev) {
 		dev_err(dev, "iommu domain is already attached\n");
-- 
2.0.4