Description

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.

References 5

• git.kernel.org https://git.kernel.org/stable/c/0fd003d3c708c80350a815eaf37b8e1114b976cf
• git.kernel.org https://git.kernel.org/stable/c/5451efb2ca30f3c42b9efb8327ce35b62870dbd3
• git.kernel.org https://git.kernel.org/stable/c/6512c9498fcb97e7c760e3ef86b2272f2c0f765f
• git.kernel.org https://git.kernel.org/stable/c/c4d344163c3a7f90712525f931a6c016bbb35e18
• git.kernel.org https://git.kernel.org/stable/c/ce50c612458091d926ccb05d7db11d9f93532db2

Remediation