Potential denial of service through cron expression form validation

The form validation for cron expressions e.g. "Poll SCM", "Build periodically" could enter infinite loops when cron expressions only matching certain rare dates were entered, blocking request handling threads indefinitely...

Cron expression form validation could enter infinite loop, potentially resulting in denial of service

The form validation for cron expressions e.g. "Poll SCM", "Build periodically" could enter infinite loops when cron expressions only matching certain rare dates were entered, blocking request handling threads indefinitely...