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;
Date:   Sun, 26 Aug 2018 23:43:22 +0100
From:   Al Viro <viro@ZenIV.linux.org.uk>
To:     Joe Perches <joe@perches.com>
Cc:     Julia Lawall <julia.lawall@lip6.fr>,
        Kees Cook <keescook@chromium.org>,
        LKML <linux-kernel@vger.kernel.org>,
        Jamal Hadi Salim <jhs@mojatatu.com>,
        Cong Wang <xiyou.wangcong@gmail.com>,
        Jiri Pirko <jiri@resnulli.us>,
        "David S. Miller" <davem@davemloft.net>,
        Network Development <netdev@vger.kernel.org>
Subject: Re: [PATCH] net: sched: Fix memory exposure from short TCA_U32_SEL
Message-ID: <20180826224322.GX6515@ZenIV.linux.org.uk>
References: <20180826055801.GA42063@beast>
 <20180826061534.GT6515@ZenIV.linux.org.uk>
 <CAGXu5jK7VzayzZTcxgZBf-+YHWO+Hv7s8utj2rzTc3gFtA8pFQ@mail.gmail.com>
 <20180826173236.GU6515@ZenIV.linux.org.uk>
 <d31fe59160e0b7d40e09536a3c74619ebb1f3b13.camel@perches.com>
 <20180826212421.GW6515@ZenIV.linux.org.uk>
 <eca48539a3dede3bfaed9ab9a6c06794cf8160e0.camel@perches.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <eca48539a3dede3bfaed9ab9a6c06794cf8160e0.camel@perches.com>
User-Agent: Mutt/1.9.1 (2017-09-22)
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

On Sun, Aug 26, 2018 at 03:26:54PM -0700, Joe Perches wrote:
> On Sun, 2018-08-26 at 22:24 +0100, Al Viro wrote:
> > On Sun, Aug 26, 2018 at 11:57:57AM -0700, Joe Perches wrote:
> > 
> > > > That, BTW, is why I hate the use of sizeof(*p) in kmalloc, etc.
> > > > arguments.  typeof is even worse in that respect.
> > > 
> > > True.  Semantic searches via tools like coccinelle could help here
> > > but those searches are quite a bit slower than straightforward greps.
> > 
> > Those searches are .config-sensitive as well, which can be much more
> > unpleasant than being slow...
> 
> Are they?  Julia?

They work pretty much on preprocessor output level; if something it ifdef'ed
out on given config, it won't be seen...