linux-kernel - Re: [RFC v3 19/45] richacl: Also recognize nontrivial mode-equivalent acls

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Date:	Wed, 27 May 2015 11:24:49 +0200
From:	Andreas Grünbacher <andreas.gruenbacher@...il.com>
To:	"J. Bruce Fields" <bfields@...ldses.org>
Cc:	linux-kernel@...r.kernel.org, linux-fsdevel@...r.kernel.org,
	linux-nfs@...r.kernel.org
Subject: Re: [RFC v3 19/45] richacl: Also recognize nontrivial mode-equivalent acls

Bruce,

2015-05-15 22:51 GMT+02:00 J. Bruce Fields <bfields@...ldses.org>:
> On Fri, Apr 24, 2015 at 01:04:16PM +0200, Andreas Gruenbacher wrote:
> This comment is a little confusing:
>
>> + * This function does not consider the masks in @acl.
>
> Given that we do this later:
>
>> +     if (acl->a_flags & RICHACL_MASKED) {
>> +             owner.allowed &= acl->a_owner_mask;
>> +             group.allowed &= acl->a_group_mask;
>> +             everyone.allowed &= acl->a_other_mask;
>> +     }

Indeed, the comment seems to be a left-over from a previous version, sorry.

> I think the difference is that here you're checking that the end result
> after applying masks is mode-equivalent, whereas in riachacl_equiv_mode
> [...] you're also checking whether the masks themselves are
> mode-equivalent?

Yes.

>Is that the right thing to do?

This patch and its consequences probably weren't thought through well enough
initially. I meanwhile think that it doesn't matter if the masks themselves are
mode-equivalent and that we can drop this check.

Thanks,
Andreas
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