You don't even have to copy the filenames around and mess with changing page permissions - simply doing: static const char * const dev_null = "/dev/null"; a

You don't even have to copy the filenames around and mess with changing page permissions - simply doing: static const char * const dev_null = "/dev/null"; and then whitelisting the pointer dev_null is sufficient, because string literals are stored in the text section which is mapped read-only.