Messages in this thread | | | Date | Tue, 30 Aug 2016 16:06:06 -0700 | From | Andrew Morton <> | Subject | Re: [RESEND][PATCH] proc: Fix timerslack_ns CAP_SYS_NICE check when adjusting self |
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On Tue, 30 Aug 2016 18:46:23 -0400 Kees Cook <keescook@chromium.org> wrote:
> On Mon, Aug 22, 2016 at 7:01 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 > > > > Cc: Kees Cook <keescook@chromium.org> > > Cc: "Serge E. Hallyn" <serge@hallyn.com> > > Cc: Andrew Morton <akpm@linux-foundation.org> > > Cc: Thomas Gleixner <tglx@linutronix.de> > > CC: Arjan van de Ven <arjan@linux.intel.com> > > Cc: Oren Laadan <orenl@cellrox.com> > > Cc: Ruchi Kandoi <kandoiruchi@google.com> > > Cc: Rom Lemarchand <romlem@android.com> > > Cc: Todd Kjos <tkjos@google.com> > > Cc: Colin Cross <ccross@android.com> > > Cc: Nick Kralevich <nnk@google.com> > > Cc: Dmitry Shmidt <dimitrysh@google.com> > > Cc: Elliott Hughes <enh@google.com> > > Cc: Android Kernel Team <kernel-team@android.com> > > Acked-by: Kees Cook <keescook@chromium.org> > > Signed-off-by: John Stultz <john.stultz@linaro.org> > > Andrew, can you take this for v4.8?
Well, it fixes proc-relax-proc-tid-timerslack_ns-capability-requirements.patch, somewhat. And it textually depends on that.
Do we want all of
proc-relax-proc-tid-timerslack_ns-capability-requirements.patch proc-add-lsm-hook-checks-to-proc-tid-timerslack_ns.patch proc-fix-timerslack_ns-cap_sys_nice-check-when-adjusting-self.patch
in 4.8? If so, why?
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