selftests: firmware: Add firmware upload selftests

Add selftests to verify the firmware upload mechanism. These test
include simple firmware uploads as well as upload cancellation and
error injection. The test creates three firmware devices and verifies
that they all work correctly and independently.

Tested-by: Matthew Gerlach <matthew.gerlach@linux.intel.com>
Reviewed-by: Luis Chamberlain <mcgrof@kernel.org>
Reviewed-by: Tianfei zhang <tianfei.zhang@intel.com>
Signed-off-by: Russ Weight <russell.h.weight@intel.com>
Link: https://lore.kernel.org/r/20220426163532.114961-1-russell.h.weight@intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Revert "selftests: firmware: add CONFIG_FW_LOADER_USER_HELPER_FALLBACK to config"

This reverts commit 7492902e8d22b568463897fa967c0886764cf034.

The commit tried to address an issue discovered by Dan where he got
a message saying:

'usermode helper disabled so ignoring test'.

Dans's commit is forcing CONFIG_FW_LOADER_USER_HELPER_FALLBACK but just
having CONFIG_FW_LOADER_USER_HELPER suffices to emulate the_FALLBACK
functionality.

Dan's commit is trying to fix an issue which is hidden from a previous
commit. That issue will be addressed properly next.

Fixes: 7492902e8d22 ("selftests: firmware: add CONFIG_FW_LOADER_USER_HELPER_FALLBACK to config")
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

selftests: firmware: add CONFIG_FW_LOADER_USER_HELPER_FALLBACK to config

CONFIG_FW_LOADER_USER_HELPER_FALLBACK=y is required for fw_fallback.sh.
Without it, fw_fallback.sh fails with 'usermode helper disabled so
ignoring test'. Enable the config in selftest so that it gets built by
default.

Signed-off-by: Dan Rue <dan.rue@linaro.org>
Acked-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Shuah Khan <shuah@kernel.org>

test_firmware: enable custom fallback testing on limited kernel configs

When a kernel is not built with:

CONFIG_HAS_FW_LOADER_USER_HELPER_FALLBACK=y

We don't currently enable testing fw_fallback.sh. For kernels that
still enable the fallback mechanism, its possible to use the async
request firmware API call request_firmware_nowait() using the custom
interface to use the fallback mechanism, so we should be able to test
this but we currently cannot.

We can enable testing without CONFIG_HAS_FW_LOADER_USER_HELPER_FALLBACK=y
by relying on /proc/config.gz (CONFIG_IKCONFIG_PROC), if present. If you
don't have this we'll have no option but to rely on old heuristics for now.

We stuff the new kconfig_has() helper into our shared library as we'll
later expando on its use elsewhere.

Acked-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Luis R. Rodriguez <mcgrof@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

selftests: create test-specific kconfig fragments

Create the config file in each directory of testcase which need
more kernel configuration than the default defconfig. User could
use these configs with merge_config.sh script:

Enable config for specific testcase:
(export ARCH=xxx #for cross compiling)
./scripts/kconfig/merge_config.sh .config \
tools/testing/selftests/xxx/config

Enable configs for all testcases:
(export ARCH=xxx #for cross compiling)
./scripts/kconfig/merge_config.sh .config \
tools/testing/selftests/*/config

Signed-off-by: Bamvor Jian Zhang <bamvor.zhangjian@linaro.org>
Reviewed-by: Shuah Khan <shuahkh@osg.samsung.com>
Signed-off-by: Shuah Khan <shuahkh@osg.samsung.com>