Commit 76f89c95 authored by Cristian Marussi's avatar Cristian Marussi Committed by Sudeep Holla
Browse files

firmware: arm_scmi: Harden accesses to the sensor domains 

Accessing sensor domains descriptors by the index upon the SCMI drivers
requests through the SCMI sensor operations interface can potentially
lead to out-of-bound violations if the SCMI driver misbehave.

Add an internal consistency check before any such domains descriptors
accesses.

Link: https://lore.kernel.org/r/20220817172731.1185305-4-cristian.marussi@arm.com


Signed-off-by: default avatarCristian Marussi <cristian.marussi@arm.com>
Signed-off-by: default avatarSudeep Holla <sudeep.holla@arm.com>
parent 1ecb7d27

drivers/firmware/arm_scmi/sensors.c

+18 −4
Original line number Diff line number Diff line
@@ -762,6 +762,10 @@ static int scmi_sensor_config_get(const struct scmi_protocol_handle *ph, 
{

	int ret;

	struct scmi_xfer *t;

	struct sensors_info *si = ph->get_priv(ph);



	if (sensor_id >= si->num_sensors)

		return -EINVAL;



	ret = ph->xops->xfer_get_init(ph, SENSOR_CONFIG_GET,

				      sizeof(__le32), sizeof(__le32), &t);
@@ -771,7 +775,6 @@ static int scmi_sensor_config_get(const struct scmi_protocol_handle *ph, 
	put_unaligned_le32(sensor_id, t->tx.buf);

	ret = ph->xops->do_xfer(ph, t);

	if (!ret) {

		struct sensors_info *si = ph->get_priv(ph);

		struct scmi_sensor_info *s = si->sensors + sensor_id;



		*sensor_config = get_unaligned_le64(t->rx.buf);
@@ -788,6 +791,10 @@ static int scmi_sensor_config_set(const struct scmi_protocol_handle *ph, 
	int ret;

	struct scmi_xfer *t;

	struct scmi_msg_sensor_config_set *msg;

	struct sensors_info *si = ph->get_priv(ph);



	if (sensor_id >= si->num_sensors)

		return -EINVAL;



	ret = ph->xops->xfer_get_init(ph, SENSOR_CONFIG_SET,

				      sizeof(*msg), 0, &t);
@@ -800,7 +807,6 @@ static int scmi_sensor_config_set(const struct scmi_protocol_handle *ph, 


	ret = ph->xops->do_xfer(ph, t);

	if (!ret) {

		struct sensors_info *si = ph->get_priv(ph);

		struct scmi_sensor_info *s = si->sensors + sensor_id;



		s->sensor_config = sensor_config;
@@ -831,8 +837,11 @@ static int scmi_sensor_reading_get(const struct scmi_protocol_handle *ph, 
	int ret;

	struct scmi_xfer *t;

	struct scmi_msg_sensor_reading_get *sensor;

	struct scmi_sensor_info *s;

	struct sensors_info *si = ph->get_priv(ph);

	struct scmi_sensor_info *s = si->sensors + sensor_id;



	if (sensor_id >= si->num_sensors)

		return -EINVAL;



	ret = ph->xops->xfer_get_init(ph, SENSOR_READING_GET,

				      sizeof(*sensor), 0, &t);
@@ -841,6 +850,7 @@ static int scmi_sensor_reading_get(const struct scmi_protocol_handle *ph, 


	sensor = t->tx.buf;

	sensor->id = cpu_to_le32(sensor_id);

	s = si->sensors + sensor_id;

	if (s->async) {

		sensor->flags = cpu_to_le32(SENSOR_READ_ASYNC);

		ret = ph->xops->do_xfer_with_response(ph, t);
@@ -895,9 +905,13 @@ scmi_sensor_reading_get_timestamped(const struct scmi_protocol_handle *ph, 
	int ret;

	struct scmi_xfer *t;

	struct scmi_msg_sensor_reading_get *sensor;

	struct scmi_sensor_info *s;

	struct sensors_info *si = ph->get_priv(ph);

	struct scmi_sensor_info *s = si->sensors + sensor_id;



	if (sensor_id >= si->num_sensors)

		return -EINVAL;



	s = si->sensors + sensor_id;

	if (!count || !readings ||

	    (!s->num_axis && count > 1) || (s->num_axis && count > s->num_axis))

		return -EINVAL;