Follow @Openwall on Twitter for new release announcements and other news
[<prev] [next>] [thread-next>] [day] [month] [year] [list]
Message-ID: <20110622071707.GA4282@albatros>
Date: Wed, 22 Jun 2011 11:17:07 +0400
From: Vasiliy Kulikov <segoon@...nwall.com>
To: oss-security@...ts.openwall.com
Subject: CVE request: kernel: taskstats local DoS

"Currently a single process may register exit handlers unlimited times.
It may lead to a bloated listeners chain and very slow process terminations.
E.g. after 10KK sent TASKSTATS_CMD_ATTR_REGISTER_CPUMASKs ~300 Mb of
kernel memory is stolen for the handlers chain and "time id" shows 2-7
seconds instead of normal 0.003.  It makes it possible to exhaust all
kernel memory and to eat much of CPU time by triggerring numerous exits
on a single CPU.

The patch limits the number of times a single process may register
itself on a single CPU to one."

It makes it possible for unprivileged user eat kernel memory and CPU
without triggering OOM killer.

Was introduced in f9fd8914c1acca0d98b69d831b128d5b52f03c51.

http://lists.openwall.net/linux-kernel/2011/06/16/605


Thanks,

-- 
Vasiliy Kulikov
http://www.openwall.com - bringing security into open computing environments

Powered by blists - more mailing lists

Please check out the Open Source Software Security Wiki, which is counterpart to this mailing list.

Confused about mailing lists and their use? Read about mailing lists on Wikipedia and check out these guidelines on proper formatting of your messages.