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Date: Sat, 10 Mar 2018 01:19:16 +0100
From: Florian Westphal <fw@strlen.de>
To: Alexey Dobriyan <adobriyan@gmail.com>
Cc: akpm@linux-foundation.org, linux-kernel@vger.kernel.org,
        eric.dumazet@gmail.com, xiyou.wangcong@gmail.com, fw@strlen.de
Subject: Re: [PATCH] proc: reject "." and ".." as filenames
Message-ID: <20180310001916.GB11882@breakpoint.cc>
References: <20180310001223.GB12443@avx2>
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Alexey Dobriyan <adobriyan@gmail.com> wrote:
> Various subsystems can create files and directories in /proc
> with names directly controlled by userspace.
> 
> Which means "/", "." and ".." are no-no.
> 
> "/" split is already taken care of, do the other 2 prohibited names.

Acked-by: Florian Westphal <fw@strlen.de>

I'll send a patch for xtables too to reject bogus names
coming from userspace (syzbot reports WARN() ).