Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
Date:   Thu, 2 Sep 2021 17:54:51 +0100
From:   "Russell King (Oracle)" <linux@armlinux.org.uk>
To:     Kees Cook <keescook@chromium.org>
Cc:     Keith Packard <keithp@keithp.com>, linux-kernel@vger.kernel.org,
        Abbott Liu <liuwenliang@huawei.com>,
        Alexander Sverdlin <alexander.sverdlin@gmail.com>,
        Al Viro <viro@zeniv.linux.org.uk>,
        Andrew Morton <akpm@linux-foundation.org>,
        Anshuman Khandual <anshuman.khandual@arm.com>,
        Ard Biesheuvel <ardb@kernel.org>,
        Arnd Bergmann <arnd@arndb.de>,
        Bjorn Andersson <bjorn.andersson@linaro.org>,
        Florian Fainelli <f.fainelli@gmail.com>,
        Geert Uytterhoeven <geert+renesas@glider.be>,
        Hartley Sweeten <hsweeten@visionengravers.com>,
        Jens Axboe <axboe@kernel.dk>, Jian Cai <jiancai@google.com>,
        Joe Perches <joe@perches.com>,
        Linus Walleij <linus.walleij@linaro.org>,
        linux-arm-kernel@lists.infradead.org,
        Maninder Singh <maninder1.s@samsung.com>,
        Manivannan Sadhasivam <mani@kernel.org>,
        Marc Zyngier <maz@kernel.org>,
        Masahiro Yamada <masahiroy@kernel.org>,
        Mike Rapoport <rppt@kernel.org>,
        Nick Desaulniers <ndesaulniers@google.com>,
        Nick Desaulniers <ndesaulniers@gooogle.com>,
        Nicolas Pitre <nico@fluxnic.net>,
        Peter Zijlstra <peterz@infradead.org>,
        Thomas Gleixner <tglx@linutronix.de>,
        Uwe =?iso-8859-1?Q?Kleine-K=F6nig?= 
        <u.kleine-koenig@pengutronix.de>,
        Valentin Schneider <valentin.schneider@arm.com>,
        Vaneet Narang <v.narang@samsung.com>,
        "Wolfram Sang (Renesas)" <wsa+renesas@sang-engineering.com>,
        YiFei Zhu <yifeifz2@illinois.edu>,
        Keith Packard <keithpac@amazon.com>,
        linux-hardening@vger.kernel.org
Subject: Re: [PATCH 0/2]: ARM: Enable THREAD_INFO_IN_TASK
Message-ID: <20210902165451.GJ22278@shell.armlinux.org.uk>
References: <20210902155429.3987201-1-keithp@keithp.com>
 <202109020904.976207C@keescook>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <202109020904.976207C@keescook>
User-Agent: Mutt/1.10.1 (2018-07-13)
Sender: Russell King (Oracle) <linux@armlinux.org.uk>
Precedence: bulk

On Thu, Sep 02, 2021 at 09:07:42AM -0700, Kees Cook wrote:
> On Thu, Sep 02, 2021 at 08:54:26AM -0700, Keith Packard wrote:
> > Placing thread_info in the kernel stack leaves it vulnerable to stack
> > overflow attacks. This short series addresses that by using the
> > existing THREAD_INFO_IN_TASK infrastructure.
> 
> Very cool! Thanks for working on this. If you want, you can refer to the
> KSPP bug for this too:
> https://github.com/KSPP/linux/issues/1

Not so fast. It's buggy. I've rejected this "solution" before.

-- 
RMK's Patch system: https://www.armlinux.org.uk/developer/patches/
FTTP is here! 40Mbps down 10Mbps up. Decent connectivity at last!