linux-kernel - Re: [PATCH -tip 2/2] compiler_types.h: Add __no_sanitize

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Tue, 2 Jun 2020 20:55:37 +0200
From:   Marco Elver <elver@...gle.com>
To:     Nick Desaulniers <ndesaulniers@...gle.com>
Cc:     Miguel Ojeda <miguel.ojeda.sandonis@...il.com>,
        Will Deacon <will@...nel.org>,
        Peter Zijlstra <peterz@...radead.org>,
        Borislav Petkov <bp@...en8.de>,
        Thomas Gleixner <tglx@...utronix.de>,
        Ingo Molnar <mingo@...nel.org>,
        clang-built-linux <clang-built-linux@...glegroups.com>,
        "Paul E. McKenney" <paulmck@...nel.org>,
        Dmitry Vyukov <dvyukov@...gle.com>,
        Alexander Potapenko <glider@...gle.com>,
        Andrey Konovalov <andreyknvl@...gle.com>,
        kasan-dev <kasan-dev@...glegroups.com>,
        LKML <linux-kernel@...r.kernel.org>,
        syzbot <syzbot+dc1fa714cb070b184db5@...kaller.appspotmail.com>
Subject: Re: [PATCH -tip 2/2] compiler_types.h: Add __no_sanitize_{address,undefined}
 to noinstr

On Tue, 2 Jun 2020 at 20:49, 'Nick Desaulniers' via kasan-dev
<kasan-dev@...glegroups.com> wrote:
>
> On Tue, Jun 2, 2020 at 11:44 AM 'Marco Elver' via Clang Built Linux
> <clang-built-linux@...glegroups.com> wrote:
> >
> > Adds the portable definitions for __no_sanitize_address, and
> > __no_sanitize_undefined, and subsequently changes noinstr to use the
> > attributes to disable instrumentation via KASAN or UBSAN.
> >
> > Link: https://lore.kernel.org/lkml/000000000000d2474c05a6c938fe@google.com/
> > Reported-by: syzbot+dc1fa714cb070b184db5@...kaller.appspotmail.com
> > Signed-off-by: Marco Elver <elver@...gle.com>
>
> Currently most of our compiler attribute detection is done in
> include/linux/compiler_attributes.h; I think this should be handled
> there. +Miguel Ojeda

GCC and Clang define these very differently, and the way to query for
them is different too. All we want is a portable __no_sanitize, and
compiler-{gcc,clang}.h is the right place for that. Similar to why we
define the other __no_sanitize above the places they were added.

Thanks,
-- Marco