Messages in this thread | | | From | John Stultz <> | Date | Thu, 14 Jul 2016 09:09:33 -0700 | Subject | Re: [PATCH 2/2] proc: Add /proc/<pid>/timerslack_ns interface |
| |
On Thu, Jul 14, 2016 at 5:48 AM, Serge E. Hallyn <serge@hallyn.com> wrote: > Quoting Kees Cook (keescook@chromium.org): >> I think the original CAP_SYS_NICE should be fine. A malicious >> CAP_SYS_NICE process can do plenty of insane things, I don't feel like >> the timer slack adds to any realistic risks. > > Can someone give a detailed explanation of what you could do with > the new timerslack feature and compare it to what you can do with > sys_nice?
Looking at the man page for CAP_SYS_NICE, it looks like such a task can set a task as SCHED_FIFO, so they could fork some spinning processes and set them all SCHED_FIFO 99, in effect delaying all other tasks for an infinite amount of time.
So one might argue setting large timerslack vlaues isn't that different risk wise?
thanks -john
| |