Commit Graph

22 Commits

Author SHA1 Message Date
Cristian Marussi 4314f9f4f8 firmware: arm_scmi: Avoid using extended string-buffers sizes if not necessary
Commit b260fccaeb ("firmware: arm_scmi: Add SCMI v3.1 protocol extended
names support") moved all the name string buffers to use the extended buffer
size of 64 instead of the required 16 bytes. While that should be fine if
the firmware terminates the string before 16 bytes, there is possibility
of copying random data if the name is not NULL terminated by the firmware.

SCMI base protocol agent_name/vendor_id/sub_vendor_id are defined by the
specification as NULL-terminated ASCII strings up to 16-bytes in length.

The underlying buffers and message descriptors are currently bigger than
needed; resize them to fit only the strictly needed 16 bytes to avoid
any possible leaks when reading data from the firmware.

Change the size argument of strlcpy to use SCMI_SHORT_NAME_MAX_SIZE always
when dealing with short domain names, so as to limit the possibility that
an ill-formed non-NULL terminated short reply from the SCMI platform
firmware can leak stale content laying in the underlying transport shared
memory area.

While at that, convert all strings handling routines to use the preferred
strscpy.

Link: https://lore.kernel.org/r/20220608095530.497879-1-cristian.marussi@arm.com
Fixes: b260fccaeb ("firmware: arm_scmi: Add SCMI v3.1 protocol extended names support")
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2022-06-10 17:55:29 +01:00
Cristian Marussi 122839b58a firmware: arm_scmi: Relax base protocol sanity checks on the protocol list
Even though malformed replies from firmware must be treated carefully to
avoid memory corruption in the kernel, some out-of-spec SCMI replies can
be tolerated to avoid breaking existing deployed system, as long as they
won't cause memory issues.

Relax the sanity checks on the recieved protocol list in the base protocol
to avoid breaking one of the deployed platform whose firmware is not easily
upgradable currently.

Link: https://lore.kernel.org/r/20220523171559.472112-1-cristian.marussi@arm.com
Cc: Etienne Carriere <etienne.carriere@linaro.org>
Cc: Sudeep Holla <sudeep.holla@arm.com>
Reported-by: Nicolas Frattaroli <frattaroli.nicolas@gmail.com>
Tested-By: Frank Wunderlich <frank-w@public-files.de>
Acked-by: Michael Riesch <michael.riesch@wolfvision.net>
Acked-by: Etienne Carriere <etienne.carriere@linaro.org>
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2022-06-06 15:46:35 +01:00
Cristian Marussi 776b6c8a25 firmware: arm_scmi: Dynamically allocate implemented protocols array
Move away from a statically allocated array for holding the current set of
protocols implemented by the platform in favour of allocating it
dynamically based on the number of protocols effectively advertised by the
platform via BASE protocol exchanges.

While at that, rectify the BASE_DISCOVER_LIST_PROTOCOLS loop iterations to
terminate only when a number of protocols equal to the advertised ones has
been received, instead of looping till the platform returns no more
protocols descriptors. This new behaviour is better compliant with the
specification and it has been tested to work equally well against an SCMI
stack running on top of an official SCP firmware on a JUNO board.

Link: https://lore.kernel.org/r/20220330150551.2573938-6-cristian.marussi@arm.com
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2022-04-28 18:22:51 +01:00
Cristian Marussi 3b0041f6e1 firmware: arm_scmi: Validate BASE_DISCOVER_LIST_PROTOCOLS response
Do not blindly trust SCMI platform response about list of implemented
protocols, instead validate the reported length of the list of protocols
against the real payload size of the message reply.

Link: https://lore.kernel.org/r/20220330150551.2573938-5-cristian.marussi@arm.com
Fixes: b6f20ff8bd ("firmware: arm_scmi: add common infrastructure and support for base protocol")
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
[sudeep.holla: Added early break if loop_num_ret = 0 and simplified calc_list_sz
	calculation]
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2022-04-28 18:22:50 +01:00
Cristian Marussi 8009120e03 firmware: arm_scmi: Fix list protocols enumeration in the base protocol
While enumerating protocols implemented by the SCMI platform using
BASE_DISCOVER_LIST_PROTOCOLS, the number of returned protocols is
currently validated in an improper way since the check employs a sum
between unsigned integers that could overflow and cause the check itself
to be silently bypassed if the returned value 'loop_num_ret' is big
enough.

Fix the validation avoiding the addition.

Link: https://lore.kernel.org/r/20220330150551.2573938-4-cristian.marussi@arm.com
Fixes: b6f20ff8bd ("firmware: arm_scmi: add common infrastructure and support for base protocol")
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2022-04-28 10:48:21 +01:00
Cristian Marussi 4de1b36fae firmware: arm_scmi: Make protocols initialisation fail on basic errors
Bail out of protocol initialisation routine early when basic information
about protocol version and attributes could not be retrieved. Failing to
act this way can lead to a successfully initialized SCMI protocol which
is in fact not fully functional.

Link: https://lore.kernel.org/r/20220330150551.2573938-3-cristian.marussi@arm.com
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2022-04-28 10:47:19 +01:00
Vincent Guittot d1cbd9e0f7 firmware: arm_scmi: Fix base agent discover response
According to scmi specification, the response of the discover agent request
is made of:
- int32 status
- uint32 agent_id
- uint8 name[16]

but the current implementation doesn't take into account the agent_id field
and only allocates a rx buffer of SCMI_MAX_STR_SIZE length

Allocate the correct length for rx buffer and copy the name from the
correct offset in the response.

While no error were returned until v5.15, v5.16-rc1 fails with virtio_scmi
transport channel:

 | arm-scmi firmware:scmi0: SCMI Notifications - Core Enabled.
 | arm-scmi firmware:scmi0: SCMI Protocol v2.0 'Linaro:PMWG' Firmware version 0x2090000
 | scmi-virtio virtio0: tx:used len 28 is larger than in buflen 24

Link: https://lore.kernel.org/r/20211117081856.9932-1-vincent.guittot@linaro.org
Fixes: b6f20ff8bd ("firmware: arm_scmi: add common infrastructure and support for base protocol")
Tested-by: Cristian Marussi <cristian.marussi@arm.com>
Reviewed-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2021-11-17 11:24:50 +00:00
Cristian Marussi f5800e0bf6 firmware: arm_scmi: Add protocol modularization support
Extend SCMI protocols accounting mechanism to address possible module
usage and add the support to possibly define new protocols as loadable
modules.

Keep the standard protocols built into the SCMI core.

Link: https://lore.kernel.org/r/20210316124903.35011-38-cristian.marussi@arm.com
Tested-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2021-03-30 16:35:16 +01:00
Cristian Marussi 3cb8c95f4b firmware: arm_scmi: Cleanup events registration transient code
Remove all the events registration code used to ease the transition to the
new interface based on protocol handles.

Link: https://lore.kernel.org/r/20210316124903.35011-35-cristian.marussi@arm.com
Tested-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2021-03-30 16:35:15 +01:00
Cristian Marussi 8d3581c252 firmware: arm_scmi: Port base protocol to new interface
Port the SCMI base protocol to new protocol handles based interface.

Link: https://lore.kernel.org/r/20210316124903.35011-11-cristian.marussi@arm.com
Tested-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2021-03-29 10:00:35 +01:00
Cristian Marussi b9f7fd907c firmware: arm_scmi: Convert events registration to protocol handles
Convert all refactored events registration routines to use protocol
handles.

In order to maintain bisectability and to allow protocols and drivers
to be later ported to the new protocol handle interface one by one,
introduce here also some transient code that will be removed later
in order to ease such transition.

Link: https://lore.kernel.org/r/20210316124903.35011-8-cristian.marussi@arm.com
Tested-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2021-03-29 10:00:35 +01:00
Cristian Marussi 533c7095b1 firmware: arm_scmi: Refactor events registration
Add a new refactored protocol events registration helper and invoke it
from the centralized initialization process triggered by get_ops() and
friends.

Also add a `get_num_sources` as a new optional callback amongst protocol
events operations. Finally remove events registration call-sites from
within the legacy protocol init routines.

Link: https://lore.kernel.org/r/20210316124903.35011-7-cristian.marussi@arm.com
Tested-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2021-03-29 10:00:35 +01:00
Cristian Marussi 48dc16e2e5 firmware: arm_scmi: Extend protocol registration interfaces
Extend common protocol registration routines and provide some new generic
protocols get/put helpers that can track protocols usage and automatically
perform the proper initialization and de-initialization on demand when
required.

Convert all standard protocols to use this new registration scheme while
keeping them all still using the usual initialization logic bound to SCMI
devices probing.

Link: https://lore.kernel.org/r/20210316124903.35011-2-cristian.marussi@arm.com
Tested-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2021-03-29 09:40:47 +01:00
Sudeep Holla 9724722fde firmware: arm_scmi: Add missing Rx size re-initialisation
Few commands provide the list of description partially and require
to be called consecutively until all the descriptors are fetched
completely. In such cases, we don't release the buffers and reuse
them for consecutive transmits.

However, currently we don't reset the Rx size which will be set as
per the response for the last transmit. This may result in incorrect
response size being interpretted as the firmware may repond with size
greater than the one set but we read only upto the size set by previous
response.

Let us reset the receive buffer size to max possible in such cases as
we don't know the exact size of the response.

Link:  https://lore.kernel.org/r/20201012141746.32575-1-sudeep.holla@arm.com
Fixes: b6f20ff8bd ("firmware: arm_scmi: add common infrastructure and support for base protocol")
Reported-by: Etienne Carriere <etienne.carriere@linaro.org>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2020-10-13 10:01:47 +01:00
Cristian Marussi 72a5eb9d9c firmware: arm_scmi: Remove fixed size fields from reports/scmi_event_header
Event reports are used to convey information describing events to the
registered user-callbacks: they are necessarily derived from the underlying
raw SCMI events' messages but they are not meant to expose or directly
mirror any of those messages data layout, which belong to the protocol
layer.

Using fixed size types for report fields, mirroring messages structure,
is at odd with this: get rid of them using more generic, equivalent,
typing.

Substitute scmi_event_header fixed size fields with generic types too and
shuffle around fields definitions to minimize implicit padding while
adapting involved functions.

Link: https://lore.kernel.org/r/20200710133919.39792-3-cristian.marussi@arm.com
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2020-07-13 09:40:21 +01:00
Cristian Marussi 585dfab3fb firmware: arm_scmi: Add base notifications support
Make SCMI base protocol register with the notification core.

Link: https://lore.kernel.org/r/20200701155348.52864-10-cristian.marussi@arm.com
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2020-07-01 17:07:26 +01:00
Sudeep Holla 2264417a9a firmware: arm_scmi: Update protocol commands and notification list
Add commands' enumerations and messages definitions for all existing
notify-enable commands across all protocols.

Link: https://lore.kernel.org/r/20200327143438.5382-3-cristian.marussi@arm.com
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2020-04-14 09:31:49 +01:00
Sudeep Holla aa90ac45bc firmware: arm_scmi: Use {get,put}_unaligned_le{32,64} accessors
Instead of type-casting the {tx,rx}.buf all over the place while
accessing them to read/write __le{32,64} from/to the firmware, let's
use the existing {get,put}_unaligned_le{32,64} accessors to hide all
the type cast ugliness.

Suggested-by: Philipp Zabel <p.zabel@pengutronix.de>
Reviewed-by: Philipp Zabel <p.zabel@pengutronix.de>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2019-08-12 12:23:01 +01:00
Sudeep Holla ca64b719a1 firmware: arm_scmi: use strlcpy to ensure NULL-terminated strings
Replace all the memcpy() for copying name strings from the firmware with
strlcpy() to make sure we are bounded by the source buffer size and we
also always have NULL-terminated strings.

This is needed to avoid out of bounds accesses if the firmware returns
a non-terminated string.

Reported-by: Olof Johansson <olof@lixom.net>
Acked-by: Olof Johansson <olof@lixom.net>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2018-09-10 10:08:44 +01:00
Sudeep Holla 14e297b3b8 firmware: arm_scmi: rename scmi_xfer_{init,get,put}
Just after the initial patches were queued, Jonathan Cameron mentioned
that scmi_one_xfer_{get_put} were not very clear and suggested to use
scmi_xfer_{alloc,free}. While I agree to some extent, the reason not to
have alloc/free as these are preallocated buffers and these functions
just returns a reference to free slot in that preallocated array.
However it was agreed to drop "_one" as it's implicit that we are always
dealing with one slot anyways.

This patch updates the name accordingly dropping "_one" in both {get,put}
functions. Also scmi_one_xfer_init is renamed as scmi_xfer_get_init to
reflect the fact that it gets the free slots and then initialise it.

Reported-by: Jonathan Cameron <jonathan.cameron@huawei.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2018-05-10 10:51:57 +01:00
Sudeep Holla 1baf47c2e5 firmware: arm_scmi: fix kernel-docs documentation
There are few missing descriptions for function parameters and structure
members along with certain instances where excessive function parameters
or structure members are described.

This patch fixes all of those warnings.

Reported-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2018-05-09 17:52:06 +01:00
Sudeep Holla b6f20ff8bd firmware: arm_scmi: add common infrastructure and support for base protocol
The base protocol describes the properties of the implementation and
provide generic error management. The base protocol provides commands
to describe protocol version, discover implementation specific
attributes and vendor/sub-vendor identification, list of protocols
implemented and the various agents are in the system including OSPM
and the platform. It also supports registering for notifications of
platform errors.

This protocol is mandatory. This patch adds support for the same along
with some basic infrastructure to add support for other protocols.

Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2018-02-28 16:37:57 +00:00