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Date: Tue, 30 Aug 2016 21:37:32 -0500
From: "Serge E. Hallyn" <serge@hallyn.com>
To: John Stultz <john.stultz@linaro.org>
Cc: lkml <linux-kernel@vger.kernel.org>, Kees Cook <keescook@chromium.org>,
        "Serge E. Hallyn" <serge@hallyn.com>,
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        Dmitry Shmidt <dimitrysh@google.com>, Elliott Hughes <enh@google.com>,
        Android Kernel Team <kernel-team@android.com>
Subject: Re: [RESEND][PATCH] proc: Fix timerslack_ns CAP_SYS_NICE check when
 adjusting self
Message-ID: <20160831023731.GA21475@mail.hallyn.com>
References: <1471906870-28624-1-git-send-email-john.stultz@linaro.org>
 <CALAqxLX06tFkj7DVrPDJMB3C0-N5jqpFY-J4nS0i+r7GBhGkhw@mail.gmail.com>
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On Mon, Aug 29, 2016 at 11:28:47AM -0700, John Stultz wrote:
> On Mon, Aug 22, 2016 at 4:01 PM, John Stultz <john.stultz@linaro.org> wrote:
> > In changing from checking ptrace_may_access(p, PTRACE_MODE_ATTACH_FSCREDS)
> > to capable(CAP_SYS_NICE), I missed that ptrace_my_access succeeds
> > when p == current, but the CAP_SYS_NICE doesn't.
> >
> > Thus while the previous commit was intended to loosen the needed
> > privledges to modify a processes timerslack, it needlessly restricted
> > a task modifying its own timerslack via the proc/<tid>/timerslack_ns
> > (which is permitted also via the PR_SET_TIMERSLACK method).
> >
> > This patch corrects this by checking if p == current before checking
> > the CAP_SYS_NICE value.
> >
> > This patch applies on top of my two previous patches currently in -mm
> 
> Ping? Any feedback or comments on this one?

(sorry - no objection from me on this patch, thanks)