From: David Ahern <dsahern@gmail.com>
To: Dave Jones <davej@redhat.com>,
Steven Rostedt <rostedt@goodmis.org>,
paulmck@linux.vnet.ibm.com,
Linux Kernel <linux-kernel@vger.kernel.org>
Subject: Re: suspicious RCU usage (perf)
Date: Mon, 26 Aug 2013 13:43:15 -0600 [thread overview]
Message-ID: <521BAFD3.2060404@gmail.com> (raw)
In-Reply-To: <20130826182907.GB25202@redhat.com>
On 8/26/13 12:29 PM, Dave Jones wrote:
> On Mon, Aug 26, 2013 at 02:18:14PM -0400, Steven Rostedt wrote:
> > On Mon, 26 Aug 2013 13:50:12 -0400
> > Dave Jones <davej@redhat.com> wrote:
> > >
> > > This was triggered as a regular user fwiw.
> > > I had not been running perf, or any other tracing. It was just left
> > > fuzzing over the weekend with no interaction at all.
> >
> > So you are telling me that ftrace was enabled by a regular user? If so,
> > that's a huge issue.
>
> quite.
>
> > So my question to you. If you were not running perf or any other
> > tracing, and this is all just non-root user. How the hell did perf
> > function tracing get started on your box????
>
> What mechanisms are available that would trigger it being enabled ?
>
> Is there some path through sys_perf_open_event that might be
> missing a capability check perhaps ?
Do you have /sys/kernel/debug with access permissions?
David
next prev parent reply other threads:[~2013-08-26 19:43 UTC|newest]
Thread overview: 17+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-08-26 14:58 suspicious RCU usage (perf) Dave Jones
2013-08-26 16:29 ` Paul E. McKenney
2013-08-26 17:30 ` Steven Rostedt
2013-08-26 17:50 ` Dave Jones
2013-08-26 18:18 ` Steven Rostedt
2013-08-26 18:29 ` Dave Jones
2013-08-26 19:03 ` Steven Rostedt
2013-08-27 12:16 ` Peter Zijlstra
2013-08-30 15:49 ` Frederic Weisbecker
2013-08-30 15:52 ` Frederic Weisbecker
2013-08-30 15:59 ` Peter Zijlstra
2013-08-30 16:06 ` Frederic Weisbecker
2013-08-26 19:43 ` David Ahern [this message]
2013-08-26 19:49 ` Dave Jones
2013-08-27 13:10 ` Steven Rostedt
2013-08-27 13:58 ` David Ahern
2013-08-27 14:13 ` Dave Jones
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