[PATCH 5.19 09/48] firmware: arm_scmi: Improve checks in the info_get operations

Greg Kroah-Hartman
2022-10-10T07:11:16Z

From: Cristian Marussi <cristian.marussi@arm.com>

[ Upstream commit 1ecb7d27b1af6705e9a4e94415b4d8cc8cf2fbfb ]

SCMI protocols abstract and expose a number of protocol specific
resources like clocks, sensors and so on. Information about such
specific domain resources are generally exposed via an `info_get`
protocol operation.

Improve the sanity check on these operations where needed.

Link: https://lore.kernel.org/r/20220817172731.1185305-3-cristian.marussi@arm.com
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/firmware/arm_scmi/clock.c | 6 +++++-
drivers/firmware/arm_scmi/sensors.c | 3 +++
include/linux/scmi_protocol.h | 4 ++--
3 files changed, 10 insertions(+), 3 deletions(-)

diff --git a/drivers/firmware/arm_scmi/clock.c b/drivers/firmware/arm_scmi/clock.c
index 3ed7ae0d6781..96060bf90a24 100644
--- a/drivers/firmware/arm_scmi/clock.c
+++ b/drivers/firmware/arm_scmi/clock.c
@@ -450,9 +450,13 @@ static int scmi_clock_count_get(const struct scmi_protocol_handle *ph)
static const struct scmi_clock_info *
scmi_clock_info_get(const struct scmi_protocol_handle *ph, u32 clk_id)
{
+ struct scmi_clock_info *clk;
struct clock_info *ci = ph->get_priv(ph);
- struct scmi_clock_info *clk = ci->clk + clk_id;

+ if (clk_id >= ci->num_clocks)
+ return NULL;
+
+ clk = ci->clk + clk_id;
if (!clk->name[0])
return NULL;

diff --git a/drivers/firmware/arm_scmi/sensors.c b/drivers/firmware/arm_scmi/sensors.c
index 7288c6117838..7d0c7476d206 100644
--- a/drivers/firmware/arm_scmi/sensors.c
+++ b/drivers/firmware/arm_scmi/sensors.c
@@ -948,6 +948,9 @@ scmi_sensor_info_get(const struct scmi_protocol_handle *ph, u32 sensor_id)
{
struct sensors_info *si = ph->get_priv(ph);

+ if (sensor_id >= si->num_sensors)
+ return NULL;
+
return si->sensors + sensor_id;
}

diff --git a/include/linux/scmi_protocol.h b/include/linux/scmi_protocol.h
index 704111f63993..6dd50ac82d10 100644
--- a/include/linux/scmi_protocol.h
+++ b/include/linux/scmi_protocol.h
@@ -78,7 +78,7 @@ struct scmi_protocol_handle;
struct scmi_clk_proto_ops {
int (*count_get)(const struct scmi_protocol_handle *ph);

- const struct scmi_clock_info *(*info_get)
+ const struct scmi_clock_info __must_check *(*info_get)
(const struct scmi_protocol_handle *ph, u32 clk_id);
int (*rate_get)(const struct scmi_protocol_handle *ph, u32 clk_id,
u64 *rate);
@@ -460,7 +460,7 @@ enum scmi_sensor_class {
*/
struct scmi_sensor_proto_ops {
int (*count_get)(const struct scmi_protocol_handle *ph);
- const struct scmi_sensor_info *(*info_get)
+ const struct scmi_sensor_info __must_check *(*info_get)
(const struct scmi_protocol_handle *ph, u32 sensor_id);
int (*trip_point_config)(const struct scmi_protocol_handle *ph,
u32 sensor_id, u8 trip_id, u64 trip_value);
--
2.35.1