platform/x86: make fw_attr_class constant

Since commit 43a7206b0963 ("driver core: class: make class_register() take
a const *"), the driver core allows for struct class to be in read-only
memory, so move the fw_attr_class structure to be declared at build time
placing it into read-only memory, instead of having to be dynamically
allocated at boot time.

Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Suggested-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: "Ricardo B. Marliere" <ricardo@marliere.net>
Link: https://lore.kernel.org/r/20240305-class_cleanup-platform-v1-1-9085c97b9355@marliere.net
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>

platform/x86: think-lmi: Fix password opcode ordering for workstations

The Lenovo workstations require the password opcode to be run before
the attribute value is changed (if Admin password is enabled).

Tested on some Thinkpads to confirm they are OK with this order too.

Signed-off-by: Mark Pearson <mpearson-lenovo@squebb.ca>
Fixes: 640a5fa50a42 ("platform/x86: think-lmi: Opcode support")
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Link: https://lore.kernel.org/r/20240209152359.528919-1-mpearson-lenovo@squebb.ca
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>

platform/x86: think-lmi: Use strreplace() to replace a character by nul

We can replace
p = strchrnul(str, '$OLD');
*p = '\0';
with
strreplace(str, '$OLD', '\0');
that does the compatible modification without a need of the temporary variable.

Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20230918135116.1248560-2-andriy.shevchenko@linux.intel.com
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>

platform/x86: think-lmi: Replace kstrdup() + strreplace() with kstrdup_and_replace()

Replace open coded functionalify of kstrdup_and_replace() with a call.

Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20230918135116.1248560-1-andriy.shevchenko@linux.intel.com
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>

platform/x86: think-lmi: Add bulk save feature

On Lenovo platforms there is a limitation in the number of times an
attribute can be saved. This is an architectural limitation and it limits
the number of attributes that can be modified to 48.
A solution for this is instead of the attribute being saved after every
modification allow a user to bulk set the attributes and then trigger a
final save. This allows unlimited attributes.

This patch introduces a save_settings attribute that can be configured to
either single or bulk mode by the user.
Single mode is the default but customers who want to avoid the 48
attribute limit can enable bulk mode.

Displaying the save_settings attribute will display the enabled mode.

When in bulk mode writing 'save' to the save_settings attribute will
trigger a save. Once this has been done a reboot is required before more
attributes can be modified.

Signed-off-by: Mark Pearson <mpearson-lenovo@squebb.ca>
Link: https://lore.kernel.org/r/20230919141530.4805-1-mpearson-lenovo@squebb.ca
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>

platform/x86: think-lmi: Fix reference leak

If a duplicate attribute is found using kset_find_obj(), a reference
to that attribute is returned which needs to be disposed accordingly
using kobject_put(). Move the setting name validation into a separate
function to allow for this change without having to duplicate the
cleanup code for this setting.
As a side note, a very similar bug was fixed in
commit 7295a996fdab ("platform/x86: dell-sysman: Fix reference leak"),
so it seems that the bug was copied from that driver.

Compile-tested only.

Fixes: 1bcad8e510b2 ("platform/x86: think-lmi: Fix issues with duplicate attributes")
Reviewed-by: Mark Pearson <mpearson-lenovo@squebb.ca>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Armin Wolf <W_Armin@gmx.de>
Link: https://lore.kernel.org/r/20230925142819.74525-2-W_Armin@gmx.de
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>

platform/x86: think-lmi: Use kfree_sensitive instead of kfree

key might contain private part of the key, so better use
kfree_sensitive to free it.

Signed-off-by: Wang Ming <machel@vivo.com>
Link: https://lore.kernel.org/r/20230717101114.18966-1-machel@vivo.com
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>

platform/x86: think-lmi: Don't display unnecessary authentication settings

If Opcode support is available (which is the standard for all platforms
going forward) then there is no need to have the encoding and kbdlang
attributes visible.

Signed-off-by: Mark Pearson <mpearson-lenovo@squebb.ca>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Link: https://lore.kernel.org/r/20230601200552.4396-8-mpearson-lenovo@squebb.ca
Signed-off-by: Hans de Goede <hdegoede@redhat.com>

platform/x86: think-lmi: Correct NVME index default

The NVME/HDD index used by WMI starts at 1 so corrected the default
appropriately.
Note, zero index is still permitted in case it is required on future
platforms.
Documentation updated correspondingly

Signed-off-by: Mark Pearson <mpearson-lenovo@squebb.ca>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Link: https://lore.kernel.org/r/20230601200552.4396-7-mpearson-lenovo@squebb.ca
Signed-off-by: Hans de Goede <hdegoede@redhat.com>

platform/x86: think-lmi: Correct NVME password handling

NVME passwords identifier have been standardised across the Lenovo
systems and now use udrp and adrp (user and admin level) instead of
unvp and mnvp.

This should apparently be backwards compatible.

Fixes: 640a5fa50a42 ("platform/x86: think-lmi: Opcode support")
Signed-off-by: Mark Pearson <mpearson-lenovo@squebb.ca>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Link: https://lore.kernel.org/r/20230601200552.4396-6-mpearson-lenovo@squebb.ca
Signed-off-by: Hans de Goede <hdegoede@redhat.com>

platform/x86: think-lmi: Update password fields to use BIT

Code clean up to use BIT macro as suggested.

Signed-off-by: Mark Pearson <mpearson-lenovo@squebb.ca>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Link: https://lore.kernel.org/r/20230601200552.4396-5-mpearson-lenovo@squebb.ca
Signed-off-by: Hans de Goede <hdegoede@redhat.com>

platform/x86: think-lmi: Update password attribute comments

Add comments to clarify what the different password attributes
are (as requested).

Signed-off-by: Mark Pearson <mpearson-lenovo@squebb.ca>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Link: https://lore.kernel.org/r/20230601200552.4396-4-mpearson-lenovo@squebb.ca
Signed-off-by: Hans de Goede <hdegoede@redhat.com>

platform/x86: think-lmi: Correct System password interface

The system password identification was incorrect. This means that if
the password was enabled it wouldn't be detected correctly; and setting
it would not work.
Also updated code to use TLMI_SMP_PWD instead of TLMI_SYS_PWD to be in
sync with Lenovo documentation.

Fixes: 640a5fa50a42 ("platform/x86: think-lmi: Opcode support")
Signed-off-by: Mark Pearson <mpearson-lenovo@squebb.ca>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Link: https://lore.kernel.org/r/20230601200552.4396-3-mpearson-lenovo@squebb.ca
Signed-off-by: Hans de Goede <hdegoede@redhat.com>

platform/x86: think-lmi: Enable opcode support on BIOS settings

Whilst reviewing some documentation from the FW team on using WMI on
Lenovo system I noticed that we weren't using Opcode support when
changing BIOS settings in the thinkLMI driver.

We should be doing this to ensure we're future proof as the old
non-opcode mechanism has been deprecated.

Tested on X1 Carbon G10 and G11.

Signed-off-by: Mark Pearson <mpearson-lenovo@squebb.ca>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Link: https://lore.kernel.org/r/20230601200552.4396-2-mpearson-lenovo@squebb.ca
Signed-off-by: Hans de Goede <hdegoede@redhat.com>

platform/x86: think-lmi: mutex protection around multiple WMI calls

When an attribute is being changed if the Admin account is enabled, or if
a password is being updated then multiple WMI calls are needed.
Add mutex protection to ensure no race conditions are introduced.

Fixes: b49f72e7f96d ("platform/x86: think-lmi: Certificate authentication support")
Signed-off-by: Mark Pearson <mpearson-lenovo@squebb.ca>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Link: https://lore.kernel.org/r/20230601200552.4396-1-mpearson-lenovo@squebb.ca
Signed-off-by: Hans de Goede <hdegoede@redhat.com>

platform/x86: think-lmi: Remove unnecessary casts for attributes

These casts are unnecessary and could break if structure layouts are
randomized or implementation details change.
Use the proper syntax that works without casts.

Also remove some unnecessary braces that checkpatch complains about.

Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Link: https://lore.kernel.org/r/20230329-think-lmi-attrs-v1-1-5794f2367cc2@weissschuh.net
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>

platform/x86: think-lmi: Remove custom kobject sysfs_ops

think-lmi defines its own sysfs_ops that are identical to the standard
kobj_sysfs_ops. Use the standard definitions.

Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Link: https://lore.kernel.org/r/20230314-think-lmi-sysfs_ops-v1-1-9d4f1cf9caec@weissschuh.net
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>

platform/x86: think-lmi: Properly interpret return value of tlmi_setting

The return value of tlmi_settings() is an errorcode, not an acpi_status.

Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Link: https://lore.kernel.org/r/20230312-think-lmi-status-v1-1-4e9f36322cc4@weissschuh.net
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>

platform/x86: think-lmi: Clean up display of current_value on Thinkstation

On ThinkStations on retrieving the attribute value the BIOS appends the
possible values to the string.
Clean up the display in the current_value_show function so the options
part is not displayed.

Fixes: a40cd7ef22fb ("platform/x86: think-lmi: Add WMI interface support on Lenovo platforms")
Reported by Mario Limoncello <Mario.Limonciello@amd.com>
Link: https://github.com/fwupd/fwupd/issues/5077#issuecomment-1488730526
Signed-off-by: Mark Pearson <mpearson-lenovo@squebb.ca>
Link: https://lore.kernel.org/r/20230403013120.2105-2-mpearson-lenovo@squebb.ca
Tested-by: Mario Limonciello <mario.limonciello@amd.com>
Tested-by: Mirsad Goran Todorovac <mirsad.todorovac@alu.unizg.hr>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>

platform/x86: think-lmi: Fix memory leaks when parsing ThinkStation WMI strings

My previous commit introduced a memory leak where the item allocated
from tlmi_setting was not freed.
This commit also renames it to avoid confusion with the similarly name
variable in the same function.

Fixes: 8a02d70679fc ("platform/x86: think-lmi: Add possible_values for ThinkStation")
Reported-by: Mirsad Todorovac <mirsad.todorovac@alu.unizg.hr>
Link: https://lore.kernel.org/lkml/df26ff45-8933-f2b3-25f4-6ee51ccda7d8@gmx.de/T/
Signed-off-by: Mark Pearson <mpearson-lenovo@squebb.ca>
Link: https://lore.kernel.org/r/20230403013120.2105-1-mpearson-lenovo@squebb.ca
Tested-by: Mario Limonciello <mario.limonciello@amd.com>
Tested-by: Mirsad Goran Todorovac <mirsad.todorovac@alu.unizg.hr>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>

platform/x86: think-lmi: Fix memory leak when showing current settings

When retriving a item string with tlmi_setting(), the result has to be
freed using kfree(). In current_value_show() however, malformed
item strings are not freed, causing a memory leak.
Fix this by eliminating the early return responsible for this.

Reported-by: Mirsad Goran Todorovac <mirsad.todorovac@alu.unizg.hr>
Link: https://lore.kernel.org/platform-driver-x86/01e920bc-5882-ba0c-dd15-868bf0eca0b8@alu.unizg.hr/T/#t
Tested-by: Mirsad Goran Todorovac <mirsad.todorovac@alu.unizg.hr>
Fixes: 0fdf10e5fc96 ("platform/x86: think-lmi: Split current_value to reflect only the value")
Signed-off-by: Armin Wolf <W_Armin@gmx.de>
Link: https://lore.kernel.org/r/20230331213319.41040-1-W_Armin@gmx.de
Tested-by: Mario Limonciello <mario.limonciello@amd.com>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>

platform/x86: think-lmi: Add possible_values for ThinkStation

ThinkStation platforms don't support the API to return possible_values
but instead embed it in the settings string.

Try and extract this information and set the possible_values attribute
appropriately.

Fixes: a40cd7ef22fb ("platform/x86: think-lmi: Add WMI interface support on Lenovo platforms")
Signed-off-by: Mark Pearson <mpearson-lenovo@squebb.ca>
Link: https://lore.kernel.org/r/20230320003221.561750-4-mpearson-lenovo@squebb.ca
Reviewed-by: Thomas Weißschuh <linux@weissschuh.net>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>

platform/x86: think-lmi: only display possible_values if available

Some attributes don't have any values available. In those cases don't
make the possible_values entry visible.

Fixes: a40cd7ef22fb ("platform/x86: think-lmi: Add WMI interface support on Lenovo platforms")
Signed-off-by: Mark Pearson <mpearson-lenovo@squebb.ca>
Link: https://lore.kernel.org/r/20230320003221.561750-3-mpearson-lenovo@squebb.ca
Reviewed-by: Thomas Weißschuh <linux@weissschuh.net>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>

platform/x86: think-lmi: use correct possible_values delimiters

firmware-attributes class requires that possible values are delimited
using ';' but the Lenovo firmware uses ',' instead.
Parse string and replace where appropriate.

Suggested-by: Thomas Weißschuh <linux@weissschuh.net>
Fixes: a40cd7ef22fb ("platform/x86: think-lmi: Add WMI interface support on Lenovo platforms")
Signed-off-by: Mark Pearson <mpearson-lenovo@squebb.ca>
Link: https://lore.kernel.org/r/20230320003221.561750-2-mpearson-lenovo@squebb.ca
Reviewed-by: Thomas Weißschuh <linux@weissschuh.net>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>

platform/x86: think-lmi: add missing type attribute

This driver was missing the mandatory type attribute...oops.

Add it in along with logic to determine whether the attribute is an
enumeration type or a string by parsing the possible_values attribute.

Upstream bug https://bugzilla.kernel.org/show_bug.cgi?id=216460

Fixes: a40cd7ef22fb ("platform/x86: think-lmi: Add WMI interface support on Lenovo platforms")
Signed-off-by: Mark Pearson <mpearson-lenovo@squebb.ca>
Link: https://lore.kernel.org/r/20230320003221.561750-1-mpearson-lenovo@squebb.ca
Reviewed-by: Thomas Weißschuh <linux@weissschuh.net>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>

platform/x86: think-lmi: Make kobj_type structure constant

Since commit ee6d3dd4ed48 ("driver core: make kobj_type constant.")
the driver core allows the usage of const struct kobj_type.

Take advantage of this to constify the structure definition to prevent
modification at runtime.

Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Reviewed-by: Mark Pearson <mpearson-lenovo@squebb.ca>
Link: https://lore.kernel.org/r/20230207-kobj_type-pdx86-v1-2-8e2c4fb83105@weissschuh.net
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>

platform/x86: think-lmi: Use min_t() for comparison and assignment

Simplify code by using min_t helper macro for logical evaluation
and value assignment. Use the _t variant of min macro since the
variable types are not same.
This issue is identified by coccicheck using the minmax.cocci file.

Signed-off-by: Deepak R Varma <drv@mailo.com>
Link: https://lore.kernel.org/r/Y9QupEMPFoZpWIiM@ubun2204.myguest.virtualbox.org
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>

platform/x86: think-lmi: certificate support clean ups

Complete some clean-ups as reqested from the last review as follow-ups
- Remove certificate from structure as no need to store it any more
- Clean up return code handling
- Moved freeing of signature to before admin object released (issue
seen in testing when unloading module)
- Minor code flow improvements

Signed-off-by: Mark Pearson <markpearson@lenovo.com>
Link: https://lore.kernel.org/r/20220321180624.4761-1-markpearson@lenovo.com
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>

platform/x86: think-lmi: Certificate authentication support

Implementation of certificate authentication feature for Lenovo
platforms. This allows for signed updates of BIOS settings.

Functionality supported:
- Cert support available check. At initialisation check if BIOS
supports certification authentication and if a certificate is
installed. Enable the sysfs nodes appropriately
- certificate and signature authentication attributes to enable
a user to install, update and delete a certificate using signed
signatures
- certificate_thumbprint to confirm installed certificate details
- support to go from certificate to password based authentication
- signature and save_signature attributes needed for setting BIOS
attributes using certificate authentication.

Tested on X1 Carbon G10 and X1 Yoga G7. This feature is not
generally available yet but will be released later this year.

Note, I also cleaned up the formating of the GUIDs when I was adding
the new defines. Hope that's OK to combine in this commit.

Signed-off-by: Mark Pearson <markpearson@lenovo.com>
Link: https://lore.kernel.org/r/20220317214008.3459-2-markpearson@lenovo.com
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>

platform/x86: think-lmi: Prevent underflow in index_store()

There needs to be a check to prevent negative offsets for
setting->index. I have reviewed this code and I think that the
"if (block->instance_count <= instance)" check in __query_block() will
prevent this from resulting in an out of bounds access. But it's
still worth fixing.

Fixes: 640a5fa50a42 ("platform/x86: think-lmi: Opcode support")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Link: https://lore.kernel.org/r/20211217071209.GF26548@kili
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>

platform/x86: think-lmi: Simplify tlmi_analyze() error handling a bit

Creating the tlmi_pwd_setting structs can only fail with -ENOMEM, set
ret to this once and simplify the error handling a bit.

Tested-by: Mark Pearson <markpearson@lenovo.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Link: https://lore.kernel.org/r/20211118114150.271274-2-hdegoede@redhat.com

platform/x86: think-lmi: Move kobject_init() call into tlmi_create_auth()

All callers of tlmi_create_auth() also call
kobject_init(&pwd_setting->kobj, &tlmi_pwd_setting_ktype) on the returned
tlmi_pwd_setting struct. Move this into tlmi_create_auth().

Tested-by: Mark Pearson <markpearson@lenovo.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Link: https://lore.kernel.org/r/20211118114150.271274-1-hdegoede@redhat.com

platform/x86: think-lmi: Opcode support

Implement Opcode support.
This is available on ThinkCenter and ThinkStations platforms and
gives improved password setting capabilities

Add options to configure System, HDD & NVMe passwords.
HDD & NVMe passwords need a user level (user/master) along with
drive index.

Signed-off-by: Mark Pearson <markpearson@lenovo.com>
Link: https://lore.kernel.org/r/20211117184453.2476-2-markpearson@lenovo.com
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>

platform/x86: think-lmi: Abort probe on analyze failure

A Lenovo ThinkStation S20 (4157CTO BIOS 60KT41AUS) fails to boot on
recent kernels including the think-lmi driver, due to the fact that
errors returned by the tlmi_analyze() function are ignored by
tlmi_probe(), where tlmi_sysfs_init() is called unconditionally.
This results in making use of an array of already freed, non-null
pointers and other uninitialized globals, causing all sorts of nasty
kobject and memory faults.

Make use of the analyze function return value, free a couple leaked
allocations, and remove the settings_count field, which is incremented
but never consumed.

Fixes: a40cd7ef22fb ("platform/x86: think-lmi: Add WMI interface support on Lenovo platforms")
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Reviewed-by: Mark Gross <markgross@kernel.org>
Reviewed-by: Mark Pearson <markpearson@lenovo.com>
Link: https://lore.kernel.org/r/163639463588.1330483.15850167112490200219.stgit@omen
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>

platform/x86: think-lmi: add debug_cmd

Many Lenovo BIOS's support the ability to send a debug command which
is useful for debugging and testing unreleased or early features.

Adding support for this feature as a module parameter.

Signed-off-by: Mark Pearson <markpearson@lenovo.com>
Link: https://lore.kernel.org/r/20210817001501.293501-1-markpearson@lenovo.com
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>

platform/x86: think-lmi: Fix possible mem-leaks on tlmi_analyze() error-exit

Fix 2 possible memleaks on error-exits from tlmi_analyze():

1. If the kzalloc of pwd_power fails, then not only free the atributes,
but also the allocated pwd_admin struct.

2. Freeing the attributes should also free the possible_values strings.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Link: https://lore.kernel.org/r/20210717143607.3580-3-hdegoede@redhat.com

platform/x86: think-lmi: Split kobject_init() and kobject_add() calls

tlmi_sysfs_init() calls tlmi_release_attr() on errors which calls
kobject_put() for attributes created by tlmi_analyze(), but if we
bail early because of an error, then this means that some of the
kobjects will not have been initialized yet; and we should thus not
call kobject_put() on them.

Switch from using kobject_init_and_add() inside tlmi_sysfs_init() to
initializing all the created kobjects directly in tlmi_analyze() and
only adding them from tlmi_sysfs_init(). This way all kobjects will
always be initialized when tlmi_release_attr() gets called.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Link: https://lore.kernel.org/r/20210717143607.3580-2-hdegoede@redhat.com

platform/x86: think-lmi: Move pending_reboot_attr to the attributes sysfs dir

Move the pending_reboot node under attributes dir where it should live, as
documented in: Documentation/ABI/testing/sysfs-class-firmware-attributes.

Also move the create / remove code to be together with the other code
populating / cleaning the attributes sysfs dir. In the removal path this
is necessary so that the remove is done before the
kset_unregister(tlmi_priv.attribute_kset) call.

Signed-off-by: Mark Pearson <markpearson@lenovo.com>
Co-developed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Link: https://lore.kernel.org/r/20210717143607.3580-1-hdegoede@redhat.com

platform/x86: think-lmi: Add pending_reboot support

The Think-lmi driver was missing pending_reboot support as it wasn't
available from the BIOS. Turns out this is really useful to have from
user space so implementing from a purely SW point of view.

Thanks to Mario Limonciello for guidance on how fwupd would use this.

Suggested-by: Mario Limonciello <mario.limonciello@amd.com>
Signed-off-by: Mark Pearson <markpearson@lenovo.com>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Link: https://lore.kernel.org/r/20210628222846.8830-1-markpearson@lenovo.com
Signed-off-by: Hans de Goede <hdegoede@redhat.com>

platform/x86: think-lmi: Move kfree(setting->possible_values) to tlmi_attr_setting_release()

We must not free the possible_values string before we have called
sysfs_remove_group(kobj, &tlmi_attr_group) otherwise there is a race
where a sysfs read of possible_values could reference the free-ed
memory.

Move the kfree(setting->possible_values) together with the free of the
actual tlmi_attr_setting struct to avoid this race.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>

platform/x86: think-lmi: Split current_value to reflect only the value

Currently attributes will show things like:
`BootOrderLock,Disable`
rather than just
`Disable`.

Of course this works, but the attribute is intended to be read by
userspace tools and not require further processing. That is a userspace
tool can display a drop down of `possible_values` and `current_value` is
one of them from the list.

This also aligns `think-lmi` with how `dell-wmi-sysman` works.

Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
Link: https://lore.kernel.org/r/20210622200755.12379-3-mario.limonciello@amd.com
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>

platform/x86: think-lmi: Fix issues with duplicate attributes

On an AMD based Lenovo T14, I find that the module doesn't work at
all, and instead has a traceback with messages like:

```
sysfs: cannot create duplicate filename '/devices/virtual/firmware-attributes/thinklmi/attributes/Reserved'
```

Duplicate and reserved values showing up appear to be a firmware bug,
but they shouldn't make the driver explode. So catch them and skip
them.

Fixes: a40cd7ef22fb ("platform/x86: think-lmi: Add WMI interface support on Lenovo platforms")
Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
Link: https://lore.kernel.org/r/20210622200755.12379-2-mario.limonciello@amd.com
[hdegoede@redhat.com: Add missing kfree(tlmi_priv.setting[i])]
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>

platform/x86: think-lmi: Return EINVAL when kbdlang gets set to a 0 length string

Commit 0ddcf3a6b442 ("platform/x86: think-lmi: Avoid potential read before
start of the buffer") moved the length == 0 up to before stripping the '\n'
which typically gets added when users echo a value to a sysfs-attribute
from the shell.

This avoids a potential buffer-underrun, but it also causes a behavioral
change, prior to this change "echo > kbdlang", iow writing just a single
'\n' would result in an EINVAL error, but after the change this gets
accepted setting kbdlang to an empty string.

Fix this by replacing the manual '\n' check with using strchrnul() to get
the length till '\n' or terminating 0 in one go; and then do the
length != 0 check after this.

Fixes: 0ddcf3a6b442 ("platform/x86: think-lmi: Avoid potential read before start of the buffer")
Reported-by: Juha Leppänen <juha_efku@dnainternet.net>
Suggested-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Link: https://lore.kernel.org/r/20210621193648.44138-1-hdegoede@redhat.com

platform/x86: think-lmi: Add missing MODULE_DEVICE_TABLE

This patch adds missing MODULE_DEVICE_TABLE definition which generates
correct modalias for automatic loading of this driver when it is built
as an external module.

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Zou Wei <zou_wei@huawei.com>
Link: https://lore.kernel.org/r/1623811809-65099-1-git-send-email-zou_wei@huawei.com
Signed-off-by: Hans de Goede <hdegoede@redhat.com>

platform/x86: think-lmi: Avoid potential read before start of the buffer

If length equals 0 then reading buf[length-1] will read before the start
of the buffer.

Avoid this by moving the length == 0 check up.

Cc: Mark Pearson <markpearson@lenovo.com>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Link: https://lore.kernel.org/r/20210609151752.156902-2-hdegoede@redhat.com

platform/x86: think-lmi: Fix check for admin password being set

tlmi_priv.pwd_admin->password is an array (not a pointer), so the correct
way to check for the password being set is to check for
tlmi_priv.pwd_admin->password[0] != 0.

For the second check, replace the check with checking that auth_str is
set instead.

Cc: Mark Pearson <markpearson@lenovo.com>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Reported-by: coverity-bot <keescook+coverity-bot@chromium.org>
Addresses-Coverity-ID: 1505158 ("NO_EFFECT")
Fixes: a7314b3b1d8a ("platform/x86: think-lmi: Add WMI interface support on Lenovo platforms")
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Link: https://lore.kernel.org/r/20210609151752.156902-1-hdegoede@redhat.com

platform/x86: dell-wmi-sysman/think-lmi: Make fw_attr_class global static

The dell-wmi-sysman and think-lmi kernel modules both have a global
struct class *fw_attr_class variable, leading to the following compile
errors when both are builtin:

ld: drivers/platform/x86/think-lmi.o:(.bss+0x0): multiple definition of `fw_attr_class'; drivers/platform/x86/dell/dell-wmi-sysman/sysman.o:(.bss+0x0): first defined here

In both cases the variable is only used in the file where it is declared.
Make both declarations static to avoid the linker error.

Cc: Mark Pearson <markpearson@lenovo.com>
Cc: Dell.Client.Kernel@dell.com
Reported-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Link: https://lore.kernel.org/r/20210609145952.113393-1-hdegoede@redhat.com

platform/x86: thinkpad-lmi: Remove unused display_name member from struct tlmi_pwd_setting

The struct tlmi_pwd_setting display_name member is initialized,
but never read. Remove it and the TLMI_PWDTYPE_MAXLEN define.

While at it also remove some other unused [MAX]LEN defines.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Link: https://lore.kernel.org/r/20210531135911.82582-1-hdegoede@redhat.com

platform/x86: think-lmi: Add WMI interface support on Lenovo platforms

For Lenovo platforms that support a WMI interface to the BIOS add
support, using the firmware-attributes class, to allow users to access
and modify various BIOS related settings.

Signed-off-by: Mark Pearson <markpearson@lenovo.com>
Link: https://lore.kernel.org/r/20210530223111.25929-3-markpearson@lenovo.com
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>