fork() can fail
If you have set a non-root user's process limits correctly, sending SIGKILL to all of that user's processes is likely a perfectly fine response to their fork() failing.<p>If you haven't limited the number of processes a given non-root user can start to some value the machine can handle, sending SIGKILL to all of the user's processes is probably not going to do anymore damage.<p>If a program running as root <i>doesn't</i> correctly handle fork() failing, <i>someone</i> needs to be taken out back and beaten with a stick. Maybe the person who wrote the program, maybe the person who ran it as root. But somebody.