code: public boolean checkForRWPaths() {
  
          boolean result = false;
  
          String[] lines = mountReader();
  
          if (lines == null){
              // Could not read, assume false;
              return false;
          }
  
          for (String line : lines) {
  
              // Split lines into parts
              String[] args = line.split(" ");
  
              if (args.length < 4){
                  // If we don't have enough options per line, skip this and log an error
                  QLog.e("Error formatting mount line: "+line);
                  continue;
              }
  
              String mountPoint = args[1];
              String mountOptions = args[3];
  
              for(String pathToCheck: Const.pathsThatShouldNotBeWrtiable) {
                  if (mountPoint.equalsIgnoreCase(pathToCheck)) {
  
                      // Split options out and compare against "rw" to avoid false positives
                      for (String option : mountOptions.split(",")){
  
                          if (option.equalsIgnoreCase("rw")){
                              QLog.v(pathToCheck+" path is mounted with rw permissions! "+line);
                              result = true;
                              break;
                          }
                      }
                  }
              }
          }
  
          return result;
      }
docs: When you're root you can change the permissions on common system directories, this method checks if any of these patha Const.pathsThatShouldNotBeWrtiable are writable.
  @return true if one of the dir is writable