linux-fsdevel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Christoph Hellwig <hch@infradead.org>
To: Florian Weimer <fw@deneb.enyo.de>
Cc: Christoph Hellwig <hch@infradead.org>,
	"Darrick J. Wong" <darrick.wong@oracle.com>,
	linux-xfs@vger.kernel.org, libc-alpha@sourceware.org,
	linux-fsdevel@vger.kernel.org, viro@zeniv.linux.org.uk
Subject: Re: XFS reports lchmod failure, but changes file system contents
Date: Wed, 12 Feb 2020 10:55:43 -0800	[thread overview]
Message-ID: <20200212185543.GA12993@infradead.org> (raw)
In-Reply-To: <87pnejmyhy.fsf@mid.deneb.enyo.de>

On Wed, Feb 12, 2020 at 07:50:01PM +0100, Florian Weimer wrote:
> * Christoph Hellwig:
> 
> > xfs doesn't seem all that different from the other file systems,
> > so I suspect you'll also see it with other on-disk file systems.
> > We probably need a check high up in the chmod and co code to reject
> > the operation early for O_PATH file descriptors pointing to symlinks.
> 
> We will change the glibc emulation to avoid trying to lchmod symbolic
> links in this way.  This will avoid triggering the kernel bug.

We'll still need to fix it.

> (We'd really like to get a proper fchmodat system call with a flags
> argument, though, for AT_EMPTY_PATH and AT_SYMLINK_NOFOLLOW.)

Send a patch (o find a minion to do so).

      reply	other threads:[~2020-02-12 19:11 UTC|newest]

Thread overview: 22+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-02-12 11:48 XFS reports lchmod failure, but changes file system contents Florian Weimer
2020-02-12 12:15 ` Florian Weimer
2020-02-12 16:16 ` Darrick J. Wong
2020-02-12 18:11   ` Christoph Hellwig
2020-02-12 18:37     ` Darrick J. Wong
2020-02-12 19:15       ` Florian Weimer
2020-02-12 19:51         ` Al Viro
2020-02-12 19:55           ` Rich Felker
2020-02-12 20:01           ` Florian Weimer
2020-02-12 20:17             ` Andreas Schwab
2020-02-12 20:19               ` Rich Felker
2020-02-12 20:26                 ` Florian Weimer
2020-02-12 20:38                   ` Rich Felker
2020-02-12 20:27                 ` Al Viro
2020-02-12 20:36                   ` Rich Felker
2020-02-12 20:18             ` Rich Felker
2020-02-12 20:38             ` Paul Eggert
2020-02-21  4:09             ` Aleksa Sarai
2020-02-21  5:02               ` Al Viro
2020-02-21  5:21                 ` Aleksa Sarai
2020-02-12 18:50     ` Florian Weimer
2020-02-12 18:55       ` Christoph Hellwig [this message]

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=20200212185543.GA12993@infradead.org \
    --to=hch@infradead.org \
    --cc=darrick.wong@oracle.com \
    --cc=fw@deneb.enyo.de \
    --cc=libc-alpha@sourceware.org \
    --cc=linux-fsdevel@vger.kernel.org \
    --cc=linux-xfs@vger.kernel.org \
    --cc=viro@zeniv.linux.org.uk \
    /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).