From 4de76302861c102cf3da5027d4acd2f077d94824 Mon Sep 17 00:00:00 2001
From: 3djc <lesitewebdejc@hotmail.com>
Date: Sat, 14 Nov 2020 13:28:13 +0100
Subject: [PATCH] Restore text sensors and prevent overflow (#8093)

* Fix FM sensor
---
 radio/src/telemetry/crossfire.cpp         | 7 +++----
 radio/src/telemetry/telemetry_sensors.cpp | 1 +
 radio/src/telemetry/telemetry_sensors.h   | 3 ++-
 3 files changed, 6 insertions(+), 5 deletions(-)

diff --git a/radio/src/telemetry/crossfire.cpp b/radio/src/telemetry/crossfire.cpp
index 6c876b7b7..f7f647c5f 100644
--- a/radio/src/telemetry/crossfire.cpp
+++ b/radio/src/telemetry/crossfire.cpp
@@ -178,10 +178,9 @@ void processCrossfireTelemetryFrame()
     case FLIGHT_MODE_ID:
     {
       const CrossfireSensor & sensor = crossfireSensors[FLIGHT_MODE_INDEX];
-      for (int i=0; i<min<int>(16, telemetryRxBuffer[1]-2); i+=4) {
-        uint32_t value = *((uint32_t *)&telemetryRxBuffer[3+i]);
-        setTelemetryValue(PROTOCOL_TELEMETRY_CROSSFIRE, sensor.id, 0, sensor.subId, value, sensor.unit, i);
-      }
+      auto textLength = min<int>(16, telemetryRxBuffer[1] - 1);
+      telemetryRxBuffer[textLength] = '\0';
+      setTelemetryText(PROTOCOL_TELEMETRY_CROSSFIRE, sensor.id, 0, sensor.subId, (const char *)telemetryRxBuffer + 3);
       break;
     }
 
diff --git a/radio/src/telemetry/telemetry_sensors.cpp b/radio/src/telemetry/telemetry_sensors.cpp
index 398c15961..e88807062 100644
--- a/radio/src/telemetry/telemetry_sensors.cpp
+++ b/radio/src/telemetry/telemetry_sensors.cpp
@@ -204,6 +204,7 @@ void TelemetryItem::setValue(const TelemetrySensor & sensor, int32_t val, uint32
     }
   }
   else if (unit == UNIT_TEXT) {
+    // Should be handled at telemetry protocol level
     return;
   }
   else {
diff --git a/radio/src/telemetry/telemetry_sensors.h b/radio/src/telemetry/telemetry_sensors.h
index e2fbcd498..8a44ae547 100644
--- a/radio/src/telemetry/telemetry_sensors.h
+++ b/radio/src/telemetry/telemetry_sensors.h
@@ -26,6 +26,7 @@
 constexpr int8_t TELEMETRY_SENSOR_TIMEOUT_UNAVAILABLE = -2;
 constexpr int8_t TELEMETRY_SENSOR_TIMEOUT_OLD = -1;
 constexpr int8_t TELEMETRY_SENSOR_TIMEOUT_START = 125; // * 160ms = 20s
+constexpr uint8_t TELEMETRY_SENSOR_TEXT_LENGTH = 16;
 
 class TelemetryItem
 {
@@ -74,7 +75,7 @@ class TelemetryItem
         // pilot latitude is stored in max
         // distFromEarthAxis is stored in value
       } gps;
-      char text[16];
+      char text[TELEMETRY_SENSOR_TEXT_LENGTH];
     };
 
     TelemetryItem()