From: Xiong Weimin <[email protected]> bus_find_device() returns a device reference that must be released with put_device(). viommu_get_by_fwnode() currently drops that reference before dereferencing the device to fetch the virtio-IOMMU private data.
Fetch the private data while the reference is still held, then release the device reference before returning. Signed-off-by: Xiong Weimin <[email protected]> --- drivers/iommu/virtio-iommu.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/drivers/iommu/virtio-iommu.c b/drivers/iommu/virtio-iommu.c index 587fc1319..342785c76 100644 --- a/drivers/iommu/virtio-iommu.c +++ b/drivers/iommu/virtio-iommu.c @@ -1009,12 +1009,16 @@ static int viommu_match_node(struct device *dev, const void *data) static struct viommu_dev *viommu_get_by_fwnode(struct fwnode_handle *fwnode) { + struct viommu_dev *viommu = NULL; struct device *dev = bus_find_device(virtio_bus_type, NULL, fwnode, viommu_match_node); - put_device(dev); + if (dev) { + viommu = dev_to_virtio(dev)->priv; + put_device(dev); + } - return dev ? dev_to_virtio(dev)->priv : NULL; + return viommu; } static struct iommu_device *viommu_probe_device(struct device *dev) -- 2.43.0
