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;
DMARC-Filter: OpenDMARC Filter v1.3.2 smtp.codeaurora.org C67EE606DD
Date:   Fri, 29 Jun 2018 15:19:35 -0600
From:   Jordan Crouse <jcrouse@codeaurora.org>
To:     Arnd Bergmann <arnd@arndb.de>
Cc:     Kees Cook <keescook@chromium.org>, Rob Clark <robdclark@gmail.com>,
        David Airlie <airlied@linux.ie>, linux-arm-msm@vger.kernel.org,
        dri-devel <dri-devel@lists.freedesktop.org>,
        freedreno@lists.freedesktop.org,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH] drm/msm/adreno: Remove VLA usage
Message-ID: <20180629211935.GG24526@jcrouse-lnx.qualcomm.com>
Mail-Followup-To: Arnd Bergmann <arnd@arndb.de>,
        Kees Cook <keescook@chromium.org>, Rob Clark <robdclark@gmail.com>,
        David Airlie <airlied@linux.ie>, linux-arm-msm@vger.kernel.org,
        dri-devel <dri-devel@lists.freedesktop.org>,
        freedreno@lists.freedesktop.org,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
References: <20180629184818.GA37439@beast>
 <CAK8P3a3Q9e59uqeZSLw6wqtNZYLe8LVgCO9RQGJB4D0F+3MLdg@mail.gmail.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <CAK8P3a3Q9e59uqeZSLw6wqtNZYLe8LVgCO9RQGJB4D0F+3MLdg@mail.gmail.com>
User-Agent: Mutt/1.5.21 (2010-09-15)
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

On Fri, Jun 29, 2018 at 10:47:31PM +0200, Arnd Bergmann wrote:
> On Fri, Jun 29, 2018 at 8:48 PM, Kees Cook <keescook@chromium.org> wrote:
> > In the quest to remove all stack VLA usage from the kernel[1], this
> > switches to using a kasprintf()ed buffer. Return paths are updated
> > to free the allocation.
> >
> > [1] https://lkml.kernel.org/r/CA+55aFzCG-zNmZwX4A2FQpadafLfEzK6CC=qPXydAacU1RqZWA@mail.gmail.com
> >
> > Signed-off-by: Kees Cook <keescook@chromium.org>
> > ---
> >  drivers/gpu/drm/msm/adreno/a5xx_gpu.c   |  7 +++++--
> >  drivers/gpu/drm/msm/adreno/adreno_gpu.c | 28 +++++++++++++++++--------
> >  2 files changed, 24 insertions(+), 11 deletions(-)
> 
> This seems fine, though using a fixed-length string is probably just
> as well here,
> given that the 'fwname' variable is always set to the constant string
> "a530_zap.mdt"
> at the moment, which is not very long.

We could make it fixed but since this code is only called once this
feels safer.

Jordan

-- 
The Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum,
a Linux Foundation Collaborative Project