linux-fsdevel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Al Viro <viro@ZenIV.linux.org.uk>
To: Andreas Dilger <adilger@dilger.ca>
Cc: "Andreas Grünbacher" <andreas.gruenbacher@gmail.com>,
	"Andreas Gruenbacher" <agruenba@redhat.com>,
	"Linux FS-devel Mailing List" <linux-fsdevel@vger.kernel.org>
Subject: Re: posix_acl_permission() and MAY_* flags
Date: Sat, 13 Oct 2018 05:37:38 +0100	[thread overview]
Message-ID: <20181013043738.GO32577@ZenIV.linux.org.uk> (raw)
In-Reply-To: <0C0A87C5-C1B8-42F8-A9C4-C355DDBC1B8F@dilger.ca>

On Fri, Oct 12, 2018 at 10:08:57PM -0600, Andreas Dilger wrote:

> It's not that I'm _so_ worried about the values changing, just
> that I was following the ACL code paths around, and the caller
> is passing in MAY_* flags on the one side, but then comparing
> them to values set from S_I*OTH flags on disk and it made me
> wonder if something was broken, or if it might break in the future.
> 
> I would definitely agree that S_I* flags are set in stone, but
> I've never really thought of MAY_* flags as being directly tied
> to on-disk values because there are so many more than just
> MAY_{READ,WRITE,EXECUTE} - MAY_APPEND, MAY_OPEN, etc.  I'd always
> thought of them like the EXT4_IMMUTABLE_FL on-disk flags vs.
> the S_IMMUTABLE inode flags in memory.

In theory - yes, in practice... imm/append-only are nowhere near
as common and didn't have universal values on-disk (ext* ones are
different from ufs ones, for example).

It might be worth a comment (near the definition of MAY_...,
probably mentioning that MAY_READ/MAY_WRITE/MAY_EXEC are
also equal to R_OK/W_OK/X_OK), but that's about it.

  reply	other threads:[~2018-10-13 12:13 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <1254FD78-8392-4B97-A191-EDA01B719635@whamcloud.com>
2018-10-12  0:43 ` Fwd: posix_acl_permission() and MAY_* flags Andreas Dilger
2018-10-12  9:09   ` Andreas Grünbacher
2018-10-13  3:56     ` Al Viro
2018-10-13  4:08       ` Andreas Dilger
2018-10-13  4:37         ` Al Viro [this message]
2018-10-13  3:40   ` Fwd: " Al Viro

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20181013043738.GO32577@ZenIV.linux.org.uk \
    --to=viro@zeniv.linux.org.uk \
    --cc=adilger@dilger.ca \
    --cc=agruenba@redhat.com \
    --cc=andreas.gruenbacher@gmail.com \
    --cc=linux-fsdevel@vger.kernel.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).