coreboot-kgpe-d16/payloads/libpayload
Julius Werner 3faa2c802e libpayload: usbhid: Zero-initialize all parts of usbhid instance struct
The USBHID driver zero-initializes some but not all of the fields in its
usbhid_inst_t structure. This is a problem because under some
circumstances, some of the uninitialized fields may be read and lead to
incorrect behavior. Some (broken) USB keyboards keep sending reports
that contain all zeroes even when they have no new keys... these usually
get silently ignored, but if the usbhid_inst_t structure is in an
inconsistent state where 'previous' is zeroed out but 'lastkeypress'
is non-zero because it wasn't properly initialized, these reports will
be interpreted as keyrepeats of the bogus 'lastkeypress'. This patch
changes the code to just xzalloc() the whole structure so we won't have
to worry about initialization issues anymore.

Change-Id: Ic987de2daaceaad2ae401a1e12b1bee397f802ee
Signed-off-by: Julius Werner <jwerner@chromium.org>
Reviewed-on: https://review.coreboot.org/23766
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Aaron Durbin <adurbin@chromium.org>
Reviewed-by: Paul Menzel <paulepanter@users.sourceforge.net>
Reviewed-by: Patrick Georgi <pgeorgi@google.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
2018-02-16 00:08:26 +00:00
..
arch Rename __attribute__((packed)) --> __packed 2017-07-13 19:45:59 +00:00
bin
configs libpayload: Double HEAP_SIZE in default config 2017-07-28 16:17:04 +00:00
crypto
curses libpayload/.../PDCurses: Improve compatibility with ncurses 2016-12-14 18:02:51 +01:00
drivers libpayload: usbhid: Zero-initialize all parts of usbhid instance struct 2018-02-16 00:08:26 +00:00
gdb libpayload/gdb: fix unused variable warning 2017-04-29 07:34:08 +02:00
include libpayload: Add pci_free_dev() and some boilerplate 2017-12-07 21:51:24 +00:00
libc libpayload: Add SKU ID coreboot table support 2017-12-07 01:19:38 +00:00
libcbfs libpayload: cbfs: Fix minor memory leak in some edge cases 2016-08-12 22:52:22 +02:00
liblz4 Rename __attribute__((packed)) --> __packed 2017-07-13 19:45:59 +00:00
liblzma
libpci libpayload: Add pci_free_dev() and some boilerplate 2017-12-07 21:51:24 +00:00
sample
tests
Doxyfile
Kconfig libpayload: video: Add support for font scaling with a factor 2017-08-03 20:37:07 +00:00
LICENSES
LICENSE_GPL
Makefile libpayload: fix build 2017-01-25 17:58:48 +01:00
Makefile.inc copy & update test routines from what-jenkins-does 2017-08-11 15:24:56 +00:00
README Use www.coreboot.org over coreboot.org 2017-06-07 12:05:44 +02:00

README

-------------------------------------------------------------------------------
libpayload README
-------------------------------------------------------------------------------

libpayload is a minimal library to support standalone payloads
that can be booted with firmware like coreboot. It handles the setup
code, and provides common C library symbols such as malloc() and printf().

Note: This is _not_ a standard library for use with an operating system,
rather it's only useful for coreboot payload development!
See https://www.coreboot.org for details on coreboot.


Installation
------------

 $ git clone https://review.coreboot.org/p/coreboot.git

 $ cd coreboot/payloads/libpayload

 $ make menuconfig

 $ make

 $ sudo make install (optional, will install into /opt per default)

As libpayload is for 32bit x86 systems only, you might have to install the
32bit libgcc version, otherwise your payloads will fail to compile.
On Debian systems you'd do 'apt-get install gcc-multilib' for example.


Usage
-----

Here's an example of a very simple payload (hello.c) and how to build it:

 #include <libpayload.h>

 int main(void)
 {
     printf("Hello, world!\n");
     return 0;
 }

Building the payload using the 'lpgcc' compiler wrapper:

 $ lpgcc -o hello.elf hello.c

Please see the sample/ directory for details.


Website and Mailing List
------------------------

The main website is https://www.coreboot.org/Libpayload.

For additional information, patches, and discussions, please join the
coreboot mailing list at https://www.coreboot.org/Mailinglist, where most
libpayload developers are subscribed.


Copyright and License
---------------------

See LICENSES.