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Date: Mon, 25 Jun 2012 15:28:53 -0700
From: Andrew Morton <akpm@linux-foundation.org>
To: Kees Cook <keescook@chromium.org>
Cc: linux-kernel@vger.kernel.org, Rob Landley <rob@landley.net>,
        Alexander Viro <viro@zeniv.linux.org.uk>,
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        linux-fsdevel@vger.kernel.org
Subject: Re: [PATCH v5] fs: make dumpable=2 require fully qualified path
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On Mon, 25 Jun 2012 15:20:19 -0700
Kees Cook <keescook@chromium.org> wrote:

> On Mon, Jun 25, 2012 at 3:14 PM, Andrew Morton
> <akpm@linux-foundation.org> wrote:
> > On Mon, 25 Jun 2012 11:03:27 -0700
> > Kees Cook <keescook@chromium.org> wrote:
> >
> >> Instead of introducing a suid_dumpable=3 mode and breaking all users
> >> of mode 2, this only disables the unsafe portion of mode 2 (writing to
> >> disk via relative path).
> >
> > It would be nicer to generate the warning at configuration time rather than
> > at core-dumping time. __I have a feeling that's Hard To Do, but why?
> 
> I actually feel that this is much more discoverable because anyone
> trying to figure out why a crash isn't dumping core isn't going to be
> looking back in time through their dmesg to find the warning from
> setting the sysctl. Additionally, I think it's the same kind of thing
> that the other existing "Skipping core dump" printk messages are
> reporting.

People who don't discover we changed their kernel until after they lost
an important core dump will be sad.  Do both?