Patch "firmware: arm_scmi: Harden accesses to the sensor domains" has been added to the 5.19-stable tree

[Sasha Levin <sashal@xxxxxxxxxx>]

This is a note to let you know that I've just added the patch titled

    firmware: arm_scmi: Harden accesses to the sensor domains

to the 5.19-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     firmware-arm_scmi-harden-accesses-to-the-sensor-doma.patch
and it can be found in the queue-5.19 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.



commit b2160d4d907eab80df64cb72311a23cf33a16fd1
Author: Cristian Marussi <cristian.marussi@xxxxxxx>
Date:   Wed Aug 17 18:27:28 2022 +0100

    firmware: arm_scmi: Harden accesses to the sensor domains
    
    [ Upstream commit 76f89c954788763db575fb512a40bd483864f1e9 ]
    
    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@xxxxxxx
    Signed-off-by: Cristian Marussi <cristian.marussi@xxxxxxx>
    Signed-off-by: Sudeep Holla <sudeep.holla@xxxxxxx>
    Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>

diff --git a/drivers/firmware/arm_scmi/sensors.c b/drivers/firmware/arm_scmi/sensors.c
index 7d0c7476d206..0b5853fa9d87 100644
--- a/drivers/firmware/arm_scmi/sensors.c
+++ b/drivers/firmware/arm_scmi/sensors.c
@@ -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;