From b9abb19fa5fd2d8a4be61c6cd4b2a48aa1a17f9c Mon Sep 17 00:00:00 2001 From: Shameer Kolothum Date: Wed, 3 Mar 2021 17:36:11 +0000 Subject: [PATCH] iommu: Check dev->iommu in iommu_dev_xxx functions The device iommu probe/attach might have failed leaving dev->iommu to NULL and device drivers may still invoke these functions resulting in a crash in iommu vendor driver code. Hence make sure we check that. Fixes: a3a195929d40 ("iommu: Add APIs for multiple domains per device") Signed-off-by: Shameer Kolothum Reviewed-by: Robin Murphy Link: https://lore.kernel.org/r/20210303173611.520-1-shameerali.kolothum.thodi@huawei.com Signed-off-by: Joerg Roedel --- drivers/iommu/iommu.c | 24 +++++++++++++++--------- 1 file changed, 15 insertions(+), 9 deletions(-) diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c index d0b0a15..e10cfa9 100644 --- a/drivers/iommu/iommu.c +++ b/drivers/iommu/iommu.c @@ -2878,10 +2878,12 @@ EXPORT_SYMBOL_GPL(iommu_fwspec_add_ids); */ int iommu_dev_enable_feature(struct device *dev, enum iommu_dev_features feat) { - const struct iommu_ops *ops = dev->bus->iommu_ops; + if (dev->iommu && dev->iommu->iommu_dev) { + const struct iommu_ops *ops = dev->iommu->iommu_dev->ops; - if (ops && ops->dev_enable_feat) - return ops->dev_enable_feat(dev, feat); + if (ops->dev_enable_feat) + return ops->dev_enable_feat(dev, feat); + } return -ENODEV; } @@ -2894,10 +2896,12 @@ EXPORT_SYMBOL_GPL(iommu_dev_enable_feature); */ int iommu_dev_disable_feature(struct device *dev, enum iommu_dev_features feat) { - const struct iommu_ops *ops = dev->bus->iommu_ops; + if (dev->iommu && dev->iommu->iommu_dev) { + const struct iommu_ops *ops = dev->iommu->iommu_dev->ops; - if (ops && ops->dev_disable_feat) - return ops->dev_disable_feat(dev, feat); + if (ops->dev_disable_feat) + return ops->dev_disable_feat(dev, feat); + } return -EBUSY; } @@ -2905,10 +2909,12 @@ EXPORT_SYMBOL_GPL(iommu_dev_disable_feature); bool iommu_dev_feature_enabled(struct device *dev, enum iommu_dev_features feat) { - const struct iommu_ops *ops = dev->bus->iommu_ops; + if (dev->iommu && dev->iommu->iommu_dev) { + const struct iommu_ops *ops = dev->iommu->iommu_dev->ops; - if (ops && ops->dev_feat_enabled) - return ops->dev_feat_enabled(dev, feat); + if (ops->dev_feat_enabled) + return ops->dev_feat_enabled(dev, feat); + } return false; } -- 2.7.4