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Date:   Thu, 12 May 2022 12:41:16 +0000
To:     "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        "linux-fsdevel@vger.kernel.org" <linux-fsdevel@vger.kernel.org>
From:   Simon Ser <contact@emersion.fr>
Reply-To: Simon Ser <contact@emersion.fr>
Subject: Re: procfs: open("/proc/self/fd/...") allows bypassing O_RDONLY
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On Thursday, May 12th, 2022 at 12:37, Simon Ser <contact@emersion.fr> wrote=
:

> what would be a good way to share a FD to another
> process without allowing it to write to the underlying file?

(I'm reminded that memfd + seals exist for this purpose. Still, I'd be
interested to know whether that O_RDONLY/O_RDWR behavior is intended,
because it's pretty surprising. The motivation for using O_RDONLY over
memfd seals is that it isn't Linux-specific.)