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Date: Tue, 23 Feb 2016 13:31:31 -0700
From: David Brown <david.brown@linaro.org>
To: kernel-hardening@lists.openwall.com
Cc: PaX Team <pageexec@freemail.hu>,
        Ard Biesheuvel <ard.biesheuvel@linaro.org>,
        Laura Abbott <labbott@redhat.com>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
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        Jeremy Linton <jeremy.linton@arm.com>, Arnd Bergmann <arnd@arndb.de>,
        LKML <linux-kernel@vger.kernel.org>
Subject: Re: [kernel-hardening] Re: [PATCH] lkdtm: add test for executing
 .rodata
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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@freemail.hu> 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