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Date: Sun, 30 Sep 2018 14:44:11 +1000
From: Aleksa Sarai <cyphar@cyphar.com>
To: Christian Brauner <christian@brauner.io>
Cc: Jeff Layton <jlayton@kernel.org>,
        "J. Bruce Fields" <bfields@fieldses.org>,
        Al Viro <viro@zeniv.linux.org.uk>,
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Subject: Re: [PATCH 0/3] namei: implement various scoping AT_* flags
Message-ID: <20180930044411.orcuw7xok4szqzzo@ryuk>
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On 2018-09-29, Christian Brauner <christian@brauner.io> wrote:
> > Currently I've only enabled these for openat(2) and the stat(2) family.
> > I would hope we could enable it for basically every *at(2) syscall --
> > but many of them appear to not have a @flags argument and thus we'll
> > need to add several new syscalls to do this. I'm more than happy to send
> > those patches, but I'd prefer to know that this preliminary work is
> > acceptable before doing a bunch of copy-paste to add new sets of *at(2)
> > syscalls.
>=20
> We should really make sure that we can't make due with openat() alone
> before adding a bunch of new syscalls. So there's no need to rush into
> this. :)

Yeah, I think that we could (mostly) make do with openat(2). We might
need to have renameat(2) and a few others, but if we had more support
for AT_EMPTY_PATH you should be able to just O_PATH|O_{BENEATH,XDEV,...}
and then operate on the O_PATH fd.

--=20
Aleksa Sarai
Senior Software Engineer (Containers)
SUSE Linux GmbH
<https://www.cyphar.com/>

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