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Date:   Tue, 24 May 2022 17:44:55 +0200
From:   Christian Brauner <brauner@kernel.org>
To:     Miklos Szeredi <miklos@szeredi.hu>,
        Andrii Nakryiko <andrii.nakryiko@gmail.com>
Cc:     Dave Marchevsky <davemarchevsky@fb.com>,
        linux-fsdevel@vger.kernel.org,
        Seth Forshee <sforshee@digitalocean.com>,
        Rik van Riel <riel@surriel.com>,
        kernel-team <kernel-team@fb.com>,
        Andrii Nakryiko <andrii@kernel.org>, Chris Mason <clm@fb.com>,
        Arnaldo Carvalho de Melo <acme@kernel.org>
Subject: Re: [PATCH] fuse: allow CAP_SYS_ADMIN in root userns to access
 allow_other mount
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On Tue, May 24, 2022 at 09:07:34AM +0200, Miklos Szeredi wrote:
> On Tue, 24 May 2022 at 06:36, Andrii Nakryiko <andrii.nakryiko@gmail.com> wrote:
> 
> > I still think that tools like perf being able to provide good tracing
> > data is going to hurt due to this cautious rejection of access, but
> > with Kconfig we at least give an option for users to opt out of it.
> > WDYT?
> 
> I'd rather use a module option for this, always defaulting to off .
> Then sysadmin then can choose to turn this protection off if
> necessary. This would effectively be the same as "user_allow_other"
> option in /etc/fuse.conf, which fusermount interprets but the kernel
> doesn't.

Agreed. Should be properly documented.

Christian