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a7902edf56
Even though coreboot always hardcodes the FMAP offset, the same is not possible for all other tools that manipulate ROM images. Some need to manually find the FMAP by searching for it's magic number (ASCII "__FMAP__"). If we do something like 'memcmp(fmap_buffer, "__FMAP__", ...) in coreboot code, it has the unfortunate side effect that the compiler will output that very same magic number as a constant in the .rodata section to compare against. Other tools may mistake this for the "real" FMAP location and get confused. This patch reverses the constant defined in coreboot and changes the only use of it correspondingly. It is not impossible but extremely unlikely (at the current state of the art) that any compiler would be clever enough to understand this pattern and optimize it back to a straight memcmp() (GCC 4.9 definitely doesn't), so it should solve the problem at least for another few years/decades. BRANCH=veyron BUG=chromium:447051 TEST=Made sure the new binaries actually contain "__PAMF__" in their .rodata. Booted Pinky. Independently corrupted both the first and the last byte of the FMAP signature with a hex editor and confirmed that signature check fails in both cases. Change-Id: I314b5e7e4d78352f409e73a3ed0e71d1b56fe774 Signed-off-by: Stefan Reinauer <reinauer@chromium.org> Original-Commit-Id: 1359d2d4502eb34a043dffab35cf4a5b033ed65a Original-Change-Id: I725652ef2a77f7f99884b46498428c3d68cd0945 Original-Signed-off-by: Julius Werner <jwerner@chromium.org> Original-Reviewed-on: https://chromium-review.googlesource.com/240723 Original-Reviewed-by: Daisuke Nojiri <dnojiri@chromium.org> Original-Reviewed-by: David Hendricks <dhendrix@chromium.org> Reviewed-on: http://review.coreboot.org/9562 Tested-by: build bot (Jenkins) Reviewed-by: Patrick Georgi <pgeorgi@google.com> |
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| 3rdparty@2bc495fd31 | ||
| documentation | ||
| payloads | ||
| src | ||
| util | ||
| .gitignore | ||
| .gitmodules | ||
| .gitreview | ||
| COPYING | ||
| Makefile | ||
| Makefile.inc | ||
| README | ||
| toolchain.inc | ||
------------------------------------------------------------------------------- coreboot README ------------------------------------------------------------------------------- coreboot is a Free Software project aimed at replacing the proprietary BIOS (firmware) found in most computers. coreboot performs a little bit of hardware initialization and then executes additional boot logic, called a payload. With the separation of hardware initialization and later boot logic, coreboot can scale from specialized applications that run directly firmware, run operating systems in flash, load custom bootloaders, or implement firmware standards, like PC BIOS services or UEFI. This allows for systems to only include the features necessary in the target application, reducing the amount of code and flash space required. coreboot was formerly known as LinuxBIOS. Payloads -------- After the basic initialization of the hardware has been performed, any desired "payload" can be started by coreboot. See http://www.coreboot.org/Payloads for a list of supported payloads. Supported Hardware ------------------ coreboot supports a wide range of chipsets, devices, and mainboards. For details please consult: * http://www.coreboot.org/Supported_Motherboards * http://www.coreboot.org/Supported_Chipsets_and_Devices Build Requirements ------------------ * gcc / g++ * make Optional: * doxygen (for generating/viewing documentation) * iasl (for targets with ACPI support) * gdb (for better debugging facilities on some targets) * ncurses (for 'make menuconfig') * flex and bison (for regenerating parsers) Building coreboot ----------------- Please consult http://www.coreboot.org/Build_HOWTO for details. Testing coreboot Without Modifying Your Hardware ------------------------------------------------ If you want to test coreboot without any risks before you really decide to use it on your hardware, you can use the QEMU system emulator to run coreboot virtually in QEMU. Please see http://www.coreboot.org/QEMU for details. Website and Mailing List ------------------------ Further details on the project, a FAQ, many HOWTOs, news, development guidelines and more can be found on the coreboot website: http://www.coreboot.org You can contact us directly on the coreboot mailing list: http://www.coreboot.org/Mailinglist Copyright and License --------------------- The copyright on coreboot is owned by quite a large number of individual developers and companies. Please check the individual source files for details. coreboot is licensed under the terms of the GNU General Public License (GPL). Some files are licensed under the "GPL (version 2, or any later version)", and some files are licensed under the "GPL, version 2". For some parts, which were derived from other projects, other (GPL-compatible) licenses may apply. Please check the individual source files for details. This makes the resulting coreboot images licensed under the GPL, version 2.