Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752164AbdHaXsG (ORCPT ); Thu, 31 Aug 2017 19:48:06 -0400 Received: from mail-io0-f175.google.com ([209.85.223.175]:34674 "EHLO mail-io0-f175.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751794AbdHaXsC (ORCPT ); Thu, 31 Aug 2017 19:48:02 -0400 X-Google-Smtp-Source: ADKCNb79yYX0MCEWlPfNHaH7a93aapP3/CT9X6uXIThtZR4DI2FVu+AMMtVE4z1kbvyUWshtKYV1LSf9HBYNO35Sf3U= MIME-Version: 1.0 In-Reply-To: <1504095773-22895-1-git-send-email-elena.reshetova@intel.com> References: <1504095773-22895-1-git-send-email-elena.reshetova@intel.com> From: Kees Cook Date: Thu, 31 Aug 2017 16:48:00 -0700 X-Google-Sender-Auth: 9n4hK9iXqBi_m5YvuQiRduzdG9I Message-ID: Subject: Re: [PATCH 00/15] v5 kernel core pieces refcount conversions To: Elena Reshetova , Andrew Morton Cc: LKML , "linux-fsdevel@vger.kernel.org" , Peter Zijlstra , Greg KH , Al Viro , Tejun Heo , Ingo Molnar , Johannes Weiner , Li Zefan , Arnaldo Carvalho de Melo , Alexander Shishkin , Eric Paris , Arnd Bergmann , Andy Lutomirski , Thomas Gleixner , dvhart@infradead.org, "Eric W. Biederman" Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3857 Lines: 100 On Wed, Aug 30, 2017 at 5:22 AM, Elena Reshetova wrote: > Now we have at least x86 support for ARCH_HAS_REFCOUNT merged and > arm and others on their way. > > Changes in v5: > * Kees catched that the following changes in > perf_event_context.refcount and futex_pi_state.refcount > are not correct now when ARCH_HAS_REFCOUNT is enabled: > - WARN_ON(!atomic_inc_not_zero(refcount)); > + refcount_inc(refcount); > So they are now changed back to using refcount_inc_not_zero. Thanks! Reviewed-by: Kees Cook Andrew, are you able to carry these patches in -mm, since they span a bunch of core kernel areas? -Kees > > Changes in v4: > * just rebase and corrections on linux-next/master > > Changes in v3: > * SoB chain corrected > * minor corrections based on v2 feedback > * rebase on linux-next/master as of today > > Changes in v2: > * dropped already merged patches > * rebase on top of linux-next/master > * Now by default refcount_t = atomic_t (*) and uses all atomic > standard operations unless CONFIG_REFCOUNT_FULL is enabled. > This is a compromise for the systems that are critical on > performance (such as net) and cannot accept even slight delay > on the refcounter operations. > > This series, for core kernel components, replaces atomic_t reference > counters with the new refcount_t type and API (see include/linux/refcount.h). > By doing this we prevent intentional or accidental > underflows or overflows that can led to use-after-free vulnerabilities. > > The patches are fully independent and can be cherry-picked separately. > If there are no objections to the patches, please merge them via respective trees. > > > Elena Reshetova (15): > sched: convert sighand_struct.count to refcount_t > sched: convert signal_struct.sigcnt to refcount_t > sched: convert user_struct.__count to refcount_t > sched: convert numa_group.refcount to refcount_t > sched/task_struct: convert task_struct.usage to refcount_t > sched/task_struct: convert task_struct.stack_refcount to refcount_t > perf: convert perf_event_context.refcount to refcount_t > perf/ring_buffer: convert ring_buffer.refcount to refcount_t > perf/ring_buffer: convert ring_buffer.aux_refcount to refcount_t > uprobes: convert uprobe.ref to refcount_t > nsproxy: convert nsproxy.count to refcount_t > groups: convert group_info.usage to refcount_t > creds: convert cred.usage to refcount_t > futex: convert futex_pi_state.refcount to refcount_t > kcov: convert kcov.refcount to refcount_t > > fs/exec.c | 4 ++-- > fs/proc/task_nommu.c | 2 +- > include/linux/cred.h | 13 ++++++------ > include/linux/init_task.h | 7 +++--- > include/linux/nsproxy.h | 6 +++--- > include/linux/perf_event.h | 3 ++- > include/linux/sched.h | 5 +++-- > include/linux/sched/signal.h | 5 +++-- > include/linux/sched/task.h | 4 ++-- > include/linux/sched/task_stack.h | 2 +- > include/linux/sched/user.h | 5 +++-- > kernel/cred.c | 46 ++++++++++++++++++++-------------------- > kernel/events/core.c | 18 ++++++++-------- > kernel/events/internal.h | 5 +++-- > kernel/events/ring_buffer.c | 8 +++---- > kernel/events/uprobes.c | 8 +++---- > kernel/fork.c | 24 ++++++++++----------- > kernel/futex.c | 13 ++++++------ > kernel/groups.c | 2 +- > kernel/kcov.c | 9 ++++---- > kernel/nsproxy.c | 6 +++--- > kernel/sched/fair.c | 12 +++++------ > kernel/user.c | 8 +++---- > 23 files changed, 112 insertions(+), 103 deletions(-) > > -- > 2.7.4 > -- Kees Cook Pixel Security