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Date:   Mon, 23 Jan 2023 13:41:04 -0500
From:   "Colin Walters" <walters@verbum.org>
To:     "Giuseppe Scrivano" <gscrivan@redhat.com>,
        linux-kernel@vger.kernel.org
Cc:     "Kees Cook" <keescook@chromium.org>, bristot@redhat.com,
        "Eric W. Biederman" <ebiederm@xmission.com>, brauner@kernel.org,
        "Aleksa Sarai" <cyphar@cyphar.com>,
        "Al Viro" <viro@zeniv.linux.org.uk>,
        "Alexander Larsson" <alexl@redhat.com>, peterz@infradead.org,
        bmasney@redhat.com
Subject: Re: [PATCH v3 1/2] exec: add PR_HIDE_SELF_EXE prctl
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On Fri, Jan 20, 2023, at 5:25 AM, Giuseppe Scrivano wrote:
> This patch adds a new prctl called PR_HIDE_SELF_EXE which allows
> processes to hide their own /proc/*/exe file. When this prctl is
> used, every access to /proc/*/exe for the calling process will
> fail with ENOENT.

How about a mount option for procfs like `mount -t procfs procfs /proc -o rw,nosuid,nodev,magiclink-no-xdev`

Where `magiclink-no-xdev` would cause all magic links to fail to cross a pid namespace or so?