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From: Alban Crequy <alban.crequy@gmail.com>
Date: Fri, 1 Sep 2017 12:25:24 +0200
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Subject: Re: [PATCH net-next v7 08/10] bpf: Add a Landlock sandbox example
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Hi Mickaël,

On 21 August 2017 at 02:09, Mickaël Salaün <mic@digikod.net> wrote:
> Add a basic sandbox tool to create a process isolated from some part of
> the system. This sandbox create a read-only environment. It is only
> allowed to write to a character device such as a TTY:
...
> +       /*
> +        * This check allows the action on the file if it is a directory or a
> +        * pipe. Otherwise, a message is printed to the eBPF log.
> +        */
> +       if (S_ISCHR(ret) || S_ISFIFO(ret))
> +               return 0;


The comment says "directory", but the code checks for "character device".

Thanks!
Alban