HID: alps: fix use-after-free on input2 registration failure

In the Linux kernel, the following vulnerability has been resolved: HID: alps: fix use-after-free on input2 registration failure alps_input_configured() stores data->input2 before calling input_register_device(). If registration fails, input_free_device() frees the input device but data->input2 still points to the freed memory. alps_input_configured() calls hid_hw_open() before allocating input2, so URBs are already active and raw_event can fire during the failure window. A U1_SP_ABSOLUTE_REPORT_ID report arriving then causes u1_raw_event() to dereference the freed data->input2 -> use-after-free. Fix by only storing input2 into drvdata after successful registration and adding a NULL guard in the raw_event path.

Where it's fixed