Encoding page size in the ELF header

[Florian Weimer]

On 09/27/2015 10:55 AM, Andreas Schwab wrote:
> Rich Felker <dalias@libc.org> writes:
> 
>> On Sat, Sep 26, 2015 at 07:13:00PM -0400, Frank Ch. Eigler wrote:

>>> Could the app more portably use
>>>
>>> int critical_data __attribute__((section(".data.critical")));
>>>
>>> and maybe a linker script widgetry to assure padding & fetch
>>> base-addresses, and then mprotect it that way?  It would become
>>> independent of page size.
>>
>> That does not eliminate the page size dependency.
> 
> MAXPAGESIZE is available in the linker script.

But ld.so supports running binaries with a larger kernel page size than
MAXPAGESIZE, don't we?  In most cases, it does work, after all.

-- 
Florian Weimer / Red Hat Product Security