On Mon, Jun 16, 2003, Yedidyah Bar-David wrote about "Re: SOLVED: Slow Linux response during disk operations (was: Testing on various computers needed)": > On Sun, Jun 15, 2003 at 10:13:47PM +0300, Nadav Har'El wrote: > > (a while ago I gave on this list, or perhaps hackers-il, an example of > > a nasty but simple fork bomb, and explained how the only way to kill > > it was to stifle it with a friendlier fork-bomb :)). > > Sorry for not reading it (apparently wasn't here, maybe hackers-il, > but google doesn't find it), but what I usually do is kill -STOP > all of them, and only then kill -SOMETHINGTERMINAL. > Unless the user intended to abuse the system, and wrote a signal > handler for STOP, it would work well (and does in practice, with > all the OS course students I have here).
Indeed it was hackers-il. See my original message in http://groups.yahoo.com/group/hackers-il/message/2181 which shows a really nasty fork bomb in 12 bytes of shell code. and an antidote in http://groups.yahoo.com/group/hackers-il/message/2187 (please read the last message before you run anything in the first!! and don't run any of those things on a public machine!!) (and for the nitpickers, a few corrections:) http://groups.yahoo.com/group/hackers-il/message/2184 http://groups.yahoo.com/group/hackers-il/message/2183 As I explained there, the problem is that if you accidentally run this fork-bomb yourself (involving 12 bytes of shell script!) it's hard, or nearly impossible, to kill it (with -STOP or anything else) without killing all your other processes in the meantime. Some people might not find that a problem, but I do (I typically stay logged in, with dozens of open windows, for weeks. I sometimes consider logging out almost as bad as rebooting :)). -- Nadav Har'El | Monday, Jun 16 2003, 16 Sivan 5763 [EMAIL PROTECTED] |----------------------------------------- Phone: +972-53-245868, ICQ 13349191 |Cat rule #2: Bite the hand that won't http://nadav.harel.org.il |feed you fast enough. ================================================================= To unsubscribe, send mail to [EMAIL PROTECTED] with the word "unsubscribe" in the message body, e.g., run the command echo unsubscribe | mail [EMAIL PROTECTED]
