path: root/drivers/iommu
diff options
authorArtem Savkov <asavkov@redhat.com>2017-08-08 12:26:02 +0200
committerJoerg Roedel <jroedel@suse.de>2017-08-11 16:56:51 +0200
commita7990c647b35415e3dd07a077480a908678947ba (patch)
treee0a7f0065684f2aafa606291698d93b81cf525c1 /drivers/iommu
parent74ddda71f44c84af62f736a77fb9fcebe5bb436a (diff)
iommu/arm-smmu: fix null-pointer dereference in arm_smmu_add_device
Commit c54451a "iommu/arm-smmu: Fix the error path in arm_smmu_add_device" removed fwspec assignment in legacy_binding path as redundant which is wrong. It needs to be updated after fwspec initialisation in arm_smmu_register_legacy_master() as it is dereferenced later. Without this there is a NULL-pointer dereference panic during boot on some hosts. Signed-off-by: Artem Savkov <asavkov@redhat.com> Reviewed-by: Robin Murphy <robin.murphy@arm.com> Acked-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Joerg Roedel <jroedel@suse.de>
Diffstat (limited to 'drivers/iommu')
1 files changed, 7 insertions, 0 deletions
diff --git a/drivers/iommu/arm-smmu.c b/drivers/iommu/arm-smmu.c
index b97188acc4f1..2d80fa8a0634 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) {