From: Nicolas Bouchinet <nicolas.bouchinet@xxxxxxxxxxx> Hi, while reading sysctl code I encountered two sysctl proc_handler parameters common errors. The first one is to declare .data as a different type thant the return of the used .proc_handler, i.e. using proch_dointvec, thats convert a char string to signed integers, and storing the result in a .data that is backed by an unsigned int. User can then write "-1" string, which results in a different value stored in the .data variable. This can lead to type conversion errors in branches and thus to potential security issues.