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Date:   Thu, 27 Aug 2020 10:48:57 -0600
From:   Ross Zwisler <zwisler@google.com>
To:     Aleksa Sarai <cyphar@cyphar.com>
Cc:     Al Viro <viro@zeniv.linux.org.uk>, linux-kernel@vger.kernel.org,
        Mattias Nissler <mnissler@chromium.org>,
        Andrew Morton <akpm@linux-foundation.org>,
        Benjamin Gordon <bmgordon@google.com>,
        David Howells <dhowells@redhat.com>,
        Dmitry Torokhov <dtor@google.com>,
        Jesse Barnes <jsbarnes@google.com>,
        linux-fsdevel@vger.kernel.org, linux-kselftest@vger.kernel.org,
        Matthew Wilcox <willy@infradead.org>,
        Micah Morton <mortonm@google.com>,
        Raul Rangel <rrangel@google.com>, Shuah Khan <shuah@kernel.org>
Subject: Re: [PATCH v8 1/2] Add a "nosymfollow" mount option.
Message-ID: <20200827164857.GA414369@google.com>
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 <20200826204819.GA4414@google.com>
 <20200827015940.GY1236603@ZenIV.linux.org.uk>
 <20200827154139.vwuflrlvj257krnw@yavin.dot.cyphar.com>
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On Fri, Aug 28, 2020 at 01:41:39AM +1000, Aleksa Sarai wrote:
> On 2020-08-27, Al Viro <viro@zeniv.linux.org.uk> wrote:
> > On Wed, Aug 26, 2020 at 02:48:19PM -0600, Ross Zwisler wrote:
> > 
> > > Al, now that the changes to fs/namei.c have landed and we're past the merge
> > > window for v5.9, what are your thoughts on this patch and the associated test?
> > 
> > Humm...  should that be nd->path.mnt->mnt_flags or link->mnt->mnt_flags?
> > Usually it's the same thing, but they might differ.  IOW, is that about the
> > directory we'd found it in, or is it about the link itself?
> 
> Now that you mention it, I think link->mnt->mnt_flags makes more sense.
> The restriction should apply in the context of whatever filesystem
> contains the symlink, and that would matches FreeBSD's semantics (at
> least as far as I can tell from a quick look at sys/kern/vfs_lookup.c).

Yep, changing this to link->mnt->mnt_flags makes sense to me, as you're right
that we care about the link itself and not the link's parent directory.  Thank
you for the review, and I'll send out v9 momentarily.