The ft5x46 touchscreen driver for custom Linux kernels on the Xiaomi perseus-p-oss MIX 3 device through 2018-11-26 has an integer overflow and OOPS because of missing checks of the size argument in tpdbg_write in drivers/input/touchscreen/ft5x46/ft5x46_ts.c. This is exploitable for a device crash via a syscall by a crafted application on a rooted device.