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From:   Miklos Szeredi <miklos@szeredi.hu>
Date:   Fri, 15 Sep 2023 11:10:08 +0200
Message-ID: <CAJfpegsct9a9D8p==mQcAfN_pJWWbXSj4oM9LHgTQEk+KPPaAw@mail.gmail.com>
Subject: Re: [RFC PATCH 2/3] add statmnt(2) syscall
To:     Paul Moore <paul@paul-moore.com>
Cc:     Miklos Szeredi <mszeredi@redhat.com>,
        linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org,
        linux-api@vger.kernel.org, linux-man@vger.kernel.org,
        linux-security-module@vger.kernel.org, Karel Zak <kzak@redhat.com>,
        Ian Kent <raven@themaw.net>,
        David Howells <dhowells@redhat.com>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        Al Viro <viro@zeniv.linux.org.uk>,
        Christian Brauner <christian@brauner.io>,
        Amir Goldstein <amir73il@gmail.com>
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On Thu, 14 Sept 2023 at 22:40, Paul Moore <paul@paul-moore.com> wrote:
>
> On Wed, Sep 13, 2023 at 11:23=E2=80=AFAM Miklos Szeredi <mszeredi@redhat.=
com> wrote:

> ...
>
> > +static int do_statmnt(struct stmt_state *s)
> > +{
> > +       struct statmnt *sm =3D &s->sm;
> > +       struct mount *m =3D real_mount(s->mnt);
> > +
> > +       if (!capable(CAP_SYS_ADMIN) &&
> > +           !is_path_reachable(m, m->mnt.mnt_root, &s->root))
> > +               return -EPERM;
>
> I realize statmnt() is different from fstatfs(), but from an access
> control perspective they look a lot alike to me which is why I think
> we should probably have a security_sb_statfs() call here.  Same thing
> for the listmnt() syscall in patch 3/3.

Okay, makes sense.

Thanks,
Miklos