[Buildroot] [PATCH 2/2 v3] toolchain/wrapper: extend paranoid check to -isystem

[Thomas Petazzoni <thomas.petazzoni@free-electrons.com>]

Hello,

On Mon, 29 Aug 2016 17:53:59 +0200, Yann E. MORIN wrote:

> +struct unsafe_opt_s {
> +	const char *arg;
> +	size_t     len;
> +};
> +
> +/* Unsafe options are options that specify a potentialy unsafe path,
> + * that will be checked by check_unsafe_path(), below.
> + *
> + * sizeof() on a string literal includes the terminating \0.
> + */
> +#define UNSAFE_OPT(o) { #o, sizeof(#o)-1 }

I was wondering if this was really necessary. You could also have done
just:

static const char *unsafe_opts[] = {
	"-I", "-L", "-isystem", ...
}

and then use strlen() in the loop. But your solution has the advantage
that the string length is calculated once for all, so OK.

> +static const struct unsafe_opt_s unsafe_opts[] = {
> +	UNSAFE_OPT(-I),
> +	UNSAFE_OPT(-idirafter).

This definitely couldn't built: it should have a comma at the end of
the line, not a dot. I've fixed this up and applied (after testing a
bit that the behavior looks sane).

Thanks,

Thomas
-- 
Thomas Petazzoni, CTO, Free Electrons
Embedded Linux and Kernel engineering
http://free-electrons.com