firmware: arm_scmi: use strlcpy to ensure NULL-terminated strings

[ Upstream commit ca64b719 ]

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>
Signed-off-by: Sasha Levin <sashal@kernel.org>

drivers/firmware/arm_scmi/base.c

@@ -208,7 +208,7 @@ static int scmi_base_discover_agent_get(const struct scmi_handle *handle,
 
 	ret = scmi_do_xfer(handle, t);
 	if (!ret)
-		memcpy(name, t->rx.buf, SCMI_MAX_STR_SIZE);
+		strlcpy(name, t->rx.buf, SCMI_MAX_STR_SIZE);
 
 	scmi_xfer_put(handle, t);
 

drivers/firmware/arm_scmi/clock.c

@@ -111,7 +111,7 @@ static int scmi_clock_attributes_get(const struct scmi_handle *handle,
 
 	ret = scmi_do_xfer(handle, t);
 	if (!ret)
-		memcpy(clk->name, attr->name, SCMI_MAX_STR_SIZE);
+		strlcpy(clk->name, attr->name, SCMI_MAX_STR_SIZE);
 	else
 		clk->name[0] = '\0';
 

drivers/firmware/arm_scmi/perf.c

@@ -174,7 +174,7 @@ scmi_perf_domain_attributes_get(const struct scmi_handle *handle, u32 domain,
 			dom_info->mult_factor =
 					(dom_info->sustained_freq_khz * 1000) /
 					dom_info->sustained_perf_level;
-		memcpy(dom_info->name, attr->name, SCMI_MAX_STR_SIZE);
+		strlcpy(dom_info->name, attr->name, SCMI_MAX_STR_SIZE);
 	}
 
 	scmi_xfer_put(handle, t);

drivers/firmware/arm_scmi/power.c

@@ -106,7 +106,7 @@ scmi_power_domain_attributes_get(const struct scmi_handle *handle, u32 domain,
 		dom_info->state_set_notify = SUPPORTS_STATE_SET_NOTIFY(flags);
 		dom_info->state_set_async = SUPPORTS_STATE_SET_ASYNC(flags);
 		dom_info->state_set_sync = SUPPORTS_STATE_SET_SYNC(flags);
-		memcpy(dom_info->name, attr->name, SCMI_MAX_STR_SIZE);
+		strlcpy(dom_info->name, attr->name, SCMI_MAX_STR_SIZE);
 	}
 
 	scmi_xfer_put(handle, t);

drivers/firmware/arm_scmi/sensors.c

@@ -140,7 +140,7 @@ static int scmi_sensor_description_get(const struct scmi_handle *handle,
 			s = &si->sensors[desc_index + cnt];
 			s->id = le32_to_cpu(buf->desc[cnt].id);
 			s->type = SENSOR_TYPE(attrh);
-			memcpy(s->name, buf->desc[cnt].name, SCMI_MAX_STR_SIZE);
+			strlcpy(s->name, buf->desc[cnt].name, SCMI_MAX_STR_SIZE);
 		}
 
 		desc_index += num_returned;