CVE-2024-36479

In the Linux kernel, the following vulnerability has been resolved:<br /> <br /> fpga: bridge: add owner module and take its refcount<br /> <br /> The current implementation of the fpga bridge assumes that the low-level<br /> module registers a driver for the parent device and uses its owner pointer<br /> to take the module&amp;#39;s refcount. This approach is problematic since it can<br /> lead to a null pointer dereference while attempting to get the bridge if<br /> the parent device does not have a driver.<br /> <br /> To address this problem, add a module owner pointer to the fpga_bridge<br /> struct and use it to take the module&amp;#39;s refcount. Modify the function for<br /> registering a bridge to take an additional owner module parameter and<br /> rename it to avoid conflicts. Use the old function name for a helper macro<br /> that automatically sets the module that registers the bridge as the owner.<br /> This ensures compatibility with existing low-level control modules and<br /> reduces the chances of registering a bridge without setting the owner.<br /> <br /> Also, update the documentation to keep it consistent with the new interface<br /> for registering an fpga bridge.<br /> <br /> Other changes: opportunistically move put_device() from __fpga_bridge_get()<br /> to fpga_bridge_get() and of_fpga_bridge_get() to improve code clarity since<br /> the bridge device is taken in these functions.