[PATCH 5.10 359/530] iommu: Check dev->iommu in iommu_dev_xxx functions
From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Date: 2021-05-12 16:19:35
Also in:
lkml
Subsystem:
iommu subsystem, the rest · Maintainers:
Joerg Roedel, Will Deacon, Linus Torvalds
From: Shameer Kolothum <redacted>
[ Upstream commit b9abb19fa5fd2d8a4be61c6cd4b2a48aa1a17f9c ]
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 <redacted>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
Link: https://lore.kernel.org/r/20210303173611.520-1-shameerali.kolothum.thodi@huawei.com (local)
Signed-off-by: Joerg Roedel <redacted>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
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 0d9adce6d812..9b8664d388af 100644
--- a/drivers/iommu/iommu.c
+++ b/drivers/iommu/iommu.c@@ -2872,10 +2872,12 @@ EXPORT_SYMBOL_GPL(iommu_dev_has_feature); 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; }
@@ -2888,10 +2890,12 @@ 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; }
@@ -2899,10 +2903,12 @@ 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; }
--
2.30.2