Re: CVE Request -- kernel: tight loop and no preemption can cause system stall

[Kurt Seifried <kseifried () redhat com>]

On 12/21/2011 03:10 PM, Petr Matousek wrote:
> A tight loop in user level process isn't preempted unless a realtime
> process is woken up on the cpu.  Some important kernel threads such as
> events/*, kblockd/* can be blocked by the process, and the machine
> stalls.
>
> Unprivileged local user could use this flaw to DoS the system.
>
> Upstream commit:
> f26f9aff6aaf67e9a430d16c266f91b13a5bff64
>
> Reference:
> https://lkml.org/lkml/2010/11/20/212
> https://bugzilla.redhat.com/show_bug.cgi?id=769711
>
> Thanks,
Please use CVE-2011-4621 for this issue.

--

-Kurt Seifried / Red Hat Security Response Team