linux-api.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Jamie Lokier <jamie@shareable.org>
To: Christoph Hellwig <hch@infradead.org>
Cc: Pavel Shilovsky <piastry@etersoft.ru>,
	linux-fsdevel@vger.kernel.org, linux-api@vger.kernel.org
Subject: Re: [PATCH 0/2] Shared flags
Date: Tue, 11 Nov 2008 10:09:40 +0000	[thread overview]
Message-ID: <20081111100940.GA8968@shareable.org> (raw)
In-Reply-To: <20081111085211.GB2323@infradead.org>

Christoph Hellwig wrote:
> On Mon, Nov 10, 2008 at 04:58:17PM +0300, Pavel Shilovsky wrote:
> > #define O_DENYREAD      004000000 /* Do not permit read access */
> > #define O_DENYWRITE     010000000 /* Do not permit write access */
> > #define O_DENYDELETE  020000000 /* Do not permit delete or rename operations*/

>  (2) you also need to enforce these semantics in the VFS for local
>      filesystems
> 
> Now if (2) doesn't cause too much overhead I would say it's fine, if not
> I would rather avoid it.

On the face of it, they look like they have similar denial-of-service
potential as mandatory locks.  For example, a root process cleaning
out /tmp gets stuck because a user process has O_DENYDELETE set.

-- Jamie

  reply	other threads:[~2008-11-11 10:09 UTC|newest]

Thread overview: 9+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <49183DF9.9010003@etersoft.ru>
     [not found] ` <49183DF9.9010003-7qunaywFIewox3rIn2DAYQ@public.gmane.org>
2008-11-11  8:52   ` [PATCH 0/2] Shared flags Christoph Hellwig
2008-11-11 10:09     ` Jamie Lokier [this message]
2008-11-11 11:14       ` Christoph Hellwig
2008-11-13 10:08         ` Pavel Shilovsky
     [not found]           ` <491BFCBA.80208-7qunaywFIewox3rIn2DAYQ@public.gmane.org>
2008-11-13  9:25             ` Christoph Hellwig
2008-11-14  3:37               ` Jamie Lokier
2008-11-15 11:39                 ` Christoph Hellwig
     [not found]                   ` <20081115113938.GA26576-wEGCiKHe2LqWVfeAwA7xHQ@public.gmane.org>
2008-11-16  5:57                     ` Pavel Shilovsky
     [not found]               ` <20081113092554.GA3004-wEGCiKHe2LqWVfeAwA7xHQ@public.gmane.org>
2008-11-16 10:37                 ` Benny Halevy

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=20081111100940.GA8968@shareable.org \
    --to=jamie@shareable.org \
    --cc=hch@infradead.org \
    --cc=linux-api@vger.kernel.org \
    --cc=linux-fsdevel@vger.kernel.org \
    --cc=piastry@etersoft.ru \
    /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).