Re: [kernel-hardening] Re: [PATCH] lkdtm: add test for executing .rodata

[David Brown]

On Mon, Feb 22, 2016 at 12:46:28PM -0800, Kees Cook wrote:
> On Thu, Feb 18, 2016 at 1:27 PM, PaX Team <pageexec@xxxxxxxxxxx> wrote:
> > On 18 Feb 2016 at 12:34, Ard Biesheuvel wrote:
> >
> > > However, that does not fix the issue Kees is trying to solve, where a
> > > .rodata section is emitted with the "x" bit set, which causes the
> > > linker to complain:
> > >
> > > /tmp/cc50ffWw.s: Assembler messages:
> > > /tmp/cc50ffWw.s:2: Warning: setting incorrect section attributes for
> > > .rodata.text
> >
> > in that case why not use a top-level asm statement to set the section
> > and its attributes (and compile the file with fno-toplevel-reorder)?
>
> GCC really wants to declare the section. :(

Why not then just use its mechanism to set the section on the code?

static void do_nothing_rodata(void)
	__attribute__((section(".rodata")))
{
	return;
}

David