Fix Klocwork#2051,2060: Array may be outside index

* Added check to ensure _data_len is within index values.

* Had to repeat the branch statement rather than move it because of memcpy.

* Fixed bug introduced(c8ecd5f) in WString.h when "len" became protected.

Signed-off-by: Kevin Moloney <kevin.moloney@emutex.com>

Author: Kevin Moloney

libraries/CurieBle/src/BleCharacteristic.cpp

@@ -165,7 +165,7 @@ BleCharacteristic::_setValue(void)
     if (!_initialised)
         return BLE_STATUS_WRONG_STATE;
 
-    if (_data_len > _char_data.max_len)
+    if ((_data_len > BLE_MAX_ATTR_DATA_LEN) && (_data_len > _char_data.max_len))
         return BLE_STATUS_NOT_ALLOWED;
 
     status = ble_client_gatts_set_attribute_value(_handles.value_handle,
@@ -204,7 +204,7 @@ BleStatus
 BleCharacteristic::setValue(const String &str)
 {
     str.getBytes((unsigned char *)&_data, (unsigned int)_char_data.max_len, 0U);
-    _data_len = str.len + 1;
+    _data_len = str.length() + 1;
     return _setValue();
 }
 

libraries/CurieBle/src/BleDescriptor.cpp

@@ -70,6 +70,9 @@ BleDescriptor::_setValue(void)
     if (!_initialised)
         return BLE_STATUS_WRONG_STATE;
 
+    if (_desc.length > BLE_MAX_ATTR_DATA_LEN)
+        return BLE_STATUS_NOT_ALLOWED;
+
     return ble_client_gatts_set_attribute_value(_handle, _desc.length, _data, 0);
 }
 
@@ -93,7 +96,7 @@ BleStatus
 BleDescriptor::setValue(const String &str)
 {
     str.getBytes((unsigned char *)&_data, (unsigned int)BLE_MAX_ATTR_DATA_LEN, 0U);
-    _desc.length = str.len + 1;
+    _desc.length = str.length() + 1;
     return _setValue();
 }