RT-Thread Parameter lwp_syscall.c sys_select memory corruption

A vulnerability was found in RT-Thread 5.1.0. It has been rated as critical. Affected by this issue is the function sys_select of the file rt-thread/components/lwp/lwp_syscall.c of the component Parameter Handler. The manipulation of the argument timeout leads to memory corruption. The vendor explains, that "[t]he timeout parameter should be checked to check if it can be accessed correctly in kernel mode and used temporarily in kernel memory."