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Date:   Thu, 27 Jun 2019 20:58:22 -0700
From:   Kees Cook <keescook@chromium.org>
To:     "J. Bruce Fields" <bfields@fieldses.org>
Cc:     linux-nfs@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH 08/16] nfsd: escape high characters in binary data
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On Thu, Jun 27, 2019 at 04:21:24PM -0400, J. Bruce Fields wrote:
> No, I was confused: "\n" is non-printable according to isprint(), so
> ESCAPE_ANY_NP *will* escape it.  So this isn't quite so bad.  SSIDs are
> usually printed as '%*pE', so arguably we should be escaping the single
> quote character too, but at least we're not allowing line breaks
> through.  I don't know about non-ascii.

Okay, cool. Given that most things are just trying to log, it seems like
it should be safe to have %pE escape non-ascii, non-printable, \, ', and "?

And if we changing that, we're likely changing
string_escape_mem(). Looking at callers of string_escape_mem() makes my
head spin...

Anyway, I don't want to block you needlessly. What would like to have
be next steps here?

-- 
Kees Cook