From: Al Viro <viro@ZenIV.linux.org.uk>
Subject: Re: [PATCH] net: sched: Fix memory exposure from short TCA_U32_SEL
Date: Sun, 26 Aug 2018 23:43:22 +0100
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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>
To: Joe Perches <joe@perches.com>
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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...