[coreboot-gerrit] Patch merged into coreboot/master: Makefile: Add build-time overlap check for programs loaded after coreboot

[gerrit at coreboot.org]

the following patch was just integrated into master:
commit fffee873c86f88a8a4b92fd9d2e16dc3f6dc7133
Author: Julius Werner <jwerner at chromium.org>
Date:   Mon Mar 7 17:55:43 2016 -0800

    Makefile: Add build-time overlap check for programs loaded after coreboot
    
    On non-x86 platforms, coreboot uses the memlayout.ld mechanism to
    statically allocate the different memory regions it needs and guarantees
    at build time that there are no dangerous overlaps between them. At the
    end of its (ramstage) execution, however, it usually loads a payload
    (and possibly other platform-specific components) that is not integrated
    into the coreboot build system and therefore cannot provide the same
    overlap guarantees through memlayout.ld. This creates a dangerous memory
    hazard where a new component could be loaded over memory areas that are
    still in use by the code-loading ramstage and lead to arbitrary memory
    corruption bugs.
    
    This patch fills this gap in our build-time correctness guarantees by
    adding the necessary checks as a new intermediate Makefile target on
    route to assembling the final image. It will parse the memory footprint
    information of the payload (and other platform-specific post-ramstage
    components) from CBFS and compare it to a list of memory areas known to
    be still in use during late ramstage, generating a build failure in case
    of a possible hazard.
    
    BUG=chrome-os-partner:48008
    TEST=Built Oak while moving critical regions in the way of BL31 or the
    payload, observing the desired build-time errors. Built Nyan, Jerry and
    Falco without issues for good measure.
    
    Change-Id: I3ebd2c1caa4df959421265e26f9cab2c54909b68
    Signed-off-by: Julius Werner <jwerner at chromium.org>
    Reviewed-on: https://review.coreboot.org/13949
    Tested-by: build bot (Jenkins)
    Reviewed-by: Patrick Georgi <pgeorgi at google.com>


See https://review.coreboot.org/13949 for details.

-gerrit