On Tue, Aug 30, 2016 at 7:06 PM, Andrew Morton <a...@linux-foundation.org> wrote: > On Tue, 30 Aug 2016 18:46:23 -0400 Kees Cook <keesc...@chromium.org> wrote: > >> On Mon, Aug 22, 2016 at 7:01 PM, John Stultz <john.stu...@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 <keesc...@chromium.org> >> > Cc: "Serge E. Hallyn" <se...@hallyn.com> >> > Cc: Andrew Morton <a...@linux-foundation.org> >> > Cc: Thomas Gleixner <t...@linutronix.de> >> > CC: Arjan van de Ven <ar...@linux.intel.com> >> > Cc: Oren Laadan <or...@cellrox.com> >> > Cc: Ruchi Kandoi <kandoiru...@google.com> >> > Cc: Rom Lemarchand <rom...@android.com> >> > Cc: Todd Kjos <tk...@google.com> >> > Cc: Colin Cross <ccr...@android.com> >> > Cc: Nick Kralevich <n...@google.com> >> > Cc: Dmitry Shmidt <dimitr...@google.com> >> > Cc: Elliott Hughes <e...@google.com> >> > Cc: Android Kernel Team <kernel-t...@android.com> >> > Acked-by: Kees Cook <keesc...@chromium.org> >> > Signed-off-by: John Stultz <john.stu...@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?
Oh, my misunderstanding. I thought those already landed in 4.8. If not, nevermind on the "rush". :) Thanks for picking it up! -Kees -- Kees Cook Nexus Security
