Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67;
MIME-Version: 1.0
In-Reply-To: <cover.1529507994.git.andreyknvl@google.com>
References: <cover.1529507994.git.andreyknvl@google.com>
From:   Andrey Konovalov <andreyknvl@google.com>
Date:   Tue, 26 Jun 2018 14:47:50 +0200
Message-ID: <CAAeHK+zqtyGzd_CZ7qKZKU-uZjZ1Pkmod5h8zzbN0xCV26nSfg@mail.gmail.com>
Subject: Re: [PATCH v4 0/7] arm64: untag user pointers passed to the kernel
To:     Catalin Marinas <catalin.marinas@arm.com>,
        Will Deacon <will.deacon@arm.com>,
        Mark Rutland <mark.rutland@arm.com>,
        Robin Murphy <robin.murphy@arm.com>,
        Al Viro <viro@zeniv.linux.org.uk>,
        Andrey Konovalov <andreyknvl@google.com>,
        Kees Cook <keescook@chromium.org>,
        Kate Stewart <kstewart@linuxfoundation.org>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Andrew Morton <akpm@linux-foundation.org>,
        Ingo Molnar <mingo@kernel.org>,
        "Kirill A . Shutemov" <kirill.shutemov@linux.intel.com>,
        Shuah Khan <shuah@kernel.org>,
        Linux ARM <linux-arm-kernel@lists.infradead.org>,
        linux-doc@vger.kernel.org,
        Linux Memory Management List <linux-mm@kvack.org>,
        linux-arch@vger.kernel.org, linux-kselftest@vger.kernel.org,
        LKML <linux-kernel@vger.kernel.org>
Cc:     Dmitry Vyukov <dvyukov@google.com>,
        Kostya Serebryany <kcc@google.com>,
        Evgeniy Stepanov <eugenis@google.com>,
        Lee Smith <Lee.Smith@arm.com>,
        Ramana Radhakrishnan <Ramana.Radhakrishnan@arm.com>,
        Jacob Bramley <Jacob.Bramley@arm.com>,
        Ruben Ayrapetyan <Ruben.Ayrapetyan@arm.com>,
        Chintan Pandya <cpandya@codeaurora.org>
Content-Type: text/plain; charset="UTF-8"
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

On Wed, Jun 20, 2018 at 5:24 PM, Andrey Konovalov <andreyknvl@google.com> wrote:
> arm64 has a feature called Top Byte Ignore, which allows to embed pointer
> tags into the top byte of each pointer. Userspace programs (such as
> HWASan, a memory debugging tool [1]) might use this feature and pass
> tagged user pointers to the kernel through syscalls or other interfaces.
>
> This patch makes a few of the kernel interfaces accept tagged user
> pointers. The kernel is already able to handle user faults with tagged
> pointers and has the untagged_addr macro, which this patchset reuses.
>
> We're not trying to cover all possible ways the kernel accepts user
> pointers in one patchset, so this one should be considered as a start.
>
> Thanks!
>
> [1] http://clang.llvm.org/docs/HardwareAssistedAddressSanitizerDesign.html

Hi!

Is there anything I should do to move forward with this?

I've received zero replies to this patch set (v3 and v4) over the last month.

Thanks!