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>

selftests: firmware: Add ZSTD compressed file tests

It's similar like XZ compressed files. For the simplicity, both XZ
and ZSTD tests are done in a single function. The format is specified
via $COMPRESS_FORMAT and the compression function is pre-defined.

Link: https://lore.kernel.org/r/20210127154939.13288-5-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Link: https://lore.kernel.org/r/20220421152908.4718-6-tiwai@suse.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

selftests: firmware: Fix it to do root uid check and skip

firmware attempts to load test modules that require root access
and fail. Fix it to check for root uid and exit with skip code
instead.

Before this fix:

selftests: firmware: fw_run_tests.sh
modprobe: ERROR: could not insert 'test_firmware': Operation not permitted
You must have the following enabled in your kernel:
CONFIG_TEST_FIRMWARE=y
CONFIG_FW_LOADER=y
CONFIG_FW_LOADER_USER_HELPER=y
CONFIG_IKCONFIG=y
CONFIG_IKCONFIG_PROC=y
not ok 1 selftests: firmware: fw_run_tests.sh # SKIP

With this fix:

selftests: firmware: fw_run_tests.sh
skip all tests: must be run as root
not ok 1 selftests: firmware: fw_run_tests.sh # SKIP

Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
Reviwed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>

selftests: firmware: Add request_firmware_into_buf tests

Add tests cases for checking request_firmware_into_buf api.
API was introduced into kernel with no testing present previously.

Signed-off-by: Scott Branden <scott.branden@broadcom.com>
Acked-by: Luis Chamberlain <mcgrof@kernel.org>
Acked-by: Shuah Khan <skhan@linuxfoundation.org>
Link: https://lore.kernel.org/r/20190822184005.901-3-scott.branden@broadcom.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

selftests: firmware: Add compressed firmware tests

This patch adds the test cases for checking compressed firmware load.
Two more cases are added to fw_filesystem.sh:
- Both a plain file and an xz file are present, and load the former
- Only an xz file is present, and load without '.xz' suffix

The tests are enabled only when CONFIG_FW_LOADER_COMPRESS is enabled
and xz program is installed.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

selftests: firmware: fix verify_reqs() return value

commit a6a9be9270c87 ("selftests: firmware: return Kselftest Skip code
for skipped tests") by Shuah modified failures to return the special
error code of $ksft_skip (4). We have a corner case issue where we
*do* want to verify_reqs().

Cc: <stable@vger.kernel.org> # >= 4.18
Fixes: a6a9be9270c87 ("selftests: firmware: return Kselftest Skip code for for skipped tests")
Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

selftests: firmware: return Kselftest Skip code for skipped tests

When firmware test(s) get skipped because of unmet dependencies and/or
unsupported configuration, it returns 0 which is treated as a pass
by the Kselftest framework. This leads to false positive result even
when the test could not be run.

Change it to return kselftest skip code when a test gets skipped to
clearly report that the test could not be run.

Kselftest framework SKIP code is 4 and the framework prints appropriate
messages to indicate that the test is skipped.

Signed-off-by: Shuah Khan (Samsung OSG) <shuah@kernel.org>
Reviewed-by: Luis R. Rodriguez <mcgrof@kernel.org>
Signed-off-by: Shuah Khan (Samsung OSG) <shuah@kernel.org>

test_firmware: fix setting old custom fw path back on exit, second try

Commit 65c79230576 tried to clear the custom firmware path on exit by
writing a single space to the firmware_class.path parameter. This
doesn't work because nothing strips this space from the value stored
and fw_get_filesystem_firmware() only ignores zero-length paths.

Instead, write a null byte.

Fixes: 0a8adf58475 ("test: add firmware_class loader test")
Fixes: 65c79230576 ("test_firmware: fix setting old custom fw path back on exit")
Signed-off-by: Ben Hutchings <ben.hutchings@codethink.co.uk>
Acked-by: Luis R. Rodriguez <mcgrof@kernel.org>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

test_firmware: modify custom fallback tests to use unique files

Users of the custom firmware fallback interface is are not supposed to
use the firmware cache interface, this can happen if for instance the
one of the APIs which use the firmware cache is used first with one
firmware file and then the request_firmware_nowait(uevent=false) API
is used with the same file.

We'll soon become strict about this on the firmware interface to reject
such calls later, so correct the test scripts to avoid such uses as well.
We address this on the tests scripts by simply using unique names when
testing the custom fallback interface.

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

test_firmware: test three firmware kernel configs using a proc knob

Since we now have knobs to twiddle what used to be set on kernel
configurations we can build one base kernel configuration and modify
behaviour to mimic such kernel configurations to test them.

Provided you build a kernel with:

CONFIG_TEST_FIRMWARE=y
CONFIG_FW_LOADER=y
CONFIG_FW_LOADER_USER_HELPER=y
CONFIG_IKCONFIG=y
CONFIG_IKCONFIG_PROC=y

We should now be able test all possible kernel configurations
when FW_LOADER=y. Note that when FW_LOADER=m we just don't provide
the built-in functionality of the built-in firmware.

If you're on an old kernel and either don't have /proc/config.gz
(CONFIG_IKCONFIG_PROC) or haven't enabled CONFIG_FW_LOADER_USER_HELPER
we cannot run these dynamic tests, so just run both scripts just
as we used to before making blunt assumptions about your setup
and requirements exactly as we did before.

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>

test_firmware: expand on library with shared helpers

This expands our library with as many things we could find which
both scripts we use share.

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

test_firmware: add simple firmware firmware test library

We'll expland on this later, for now just add basic module checker.
While at it, move this all to use /bin/bash as we'll have much more
flexibility with it.

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