show_bad.zip should contain an executable you would be used on your PC to generate a list of bad pixels. However, this tool is very old and only supports raw files for a few old cameras. Which camera do you have?
The tools seems to use the same trick as dcraw - looking for at the RAW file size and matching that to predefined row & column dimensions.
It would not be too hard to write a script to scrape all the platform_camera.h files for CAM_RAW_ROWPIX & CAM_RAW_ROWS data and build a table covering every CHDK supported camera. The tool could use that or could be upgraded to accept a camera name from the command line.
Is this worth any effort?
