Re: embedded ROMd linux?

Matthias Urlichs (
28 Jun 1997 23:47:13 +0200 (Alan Cox) writes:
> The kernel doesn't care whether you have multiple users or not. It has
> a definite notion of rights but you can either use that usefully for
> seperating applications under a non multiuser system or just run the lot
> uid 0

The point is, why do we need all the security-checking code if there will
never be a uid != 0 on the machine ever?

A CONFIG_NO_SECURITY option which lets GCC skip all the user+group+whatever
checks (or indeed the fields in the data structures) would probably be a
good idea for embedded situations where you want to squeeze every bit your
don't need out of the kernel.

Unfortunately, the simpleminded approach of
#define suser() 1
won't work because the kernel checks suser() last, so that a future version
of suser() can log the fact that it was needed.

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