[PATCH 5.19 10/48] firmware: arm_scmi: Harden accesses to the sensor domains

Greg Kroah-Hartman
2022-10-10T07:07:57Z

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

[ 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@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/sensors.c | 22 ++++++++++++++++++----
1 file changed, 18 insertions(+), 4 deletions(-)

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;
--
2.35.1