CVE-2022-50745

In the Linux kernel, the following vulnerability has been resolved:

staging: media: tegra-video: fix device_node use after free

At probe time this code path is followed:

* tegra_csi_init

* tegra_csi_channels_alloc

* for_each_child_of_node(node, channel) -- iterates over channels

* automatically gets 'channel'

* tegra_csi_channel_alloc()

* saves into chan->of_node a pointer to the channel OF node

* automatically gets and puts 'channel'

* now the node saved in chan->of_node has refcount 0, can disappear

* tegra_csi_channels_init

* iterates over channels

* tegra_csi_channel_init -- uses chan->of_node

After that, chan->of_node keeps storing the node until the device is

removed.

of_node_get() the node and of_node_put() it during teardown to avoid any

risk.