🚀 go-pugleaf

Amos Shapira writes:
>A general suggestion for a programme which will do what you want would be:
>
>main (ac, av)
>	int ac;
>	char **av;
>{
>	exec ("/usr/etc/mount", av);
>}
>
>and have the object of this C programme suid root.

IMHO this is an extremely poor counterexample, since it lets the user
mount anything, with any options.  That presents its own security
risk.

Usually these special purpose mount wrappers are written with constant
arguments for exec.  For example, someone (I don't recall who) posted a
while ago:

char *env[]={"PATH=/usr/etc",(char*)0};
char *argv[]={"/usr/etc/mount","/pcfs",(char*)0};

main()
{
        setruid(getuid());
        execve("/usr/etc/mount",argv,env);
}

and a similar program for a cdrom, and two more programs for unmounting.

Brian