From: "J. Bruce Fields" <bfields@redhat.com>
To: Andy Shevchenko <andriy.shevchenko@intel.com>
Cc: linux-nfs@vger.kernel.org
Subject: Re: [PATCH 08/16] nfsd: escape high characters in binary data
Date: Tue, 6 Aug 2019 14:50:08 -0400 [thread overview]
Message-ID: <20190806185008.GC9456@parsley.fieldses.org> (raw)
In-Reply-To: <20190806121931.GA29578@smile.fi.intel.com>
On Tue, Aug 06, 2019 at 03:19:31PM +0300, Andy Shevchenko wrote:
> On Thu, Jun 20, 2019 at 10:51:07AM -0400, J. Bruce Fields wrote:
> > From: "J. Bruce Fields" <bfields@redhat.com>
> >
> > I'm exposing some information about NFS clients in pseudofiles. I
> > expect to eventually have simple tools to help read those pseudofiles.
> >
> > But it's also helpful if the raw files are human-readable to the extent
> > possible. It aids debugging and makes them usable on systems that don't
> > have the latest nfs-utils.
> >
> > A minor challenge there is opaque client-generated protocol objects like
> > state owners and client identifiers. Some clients generate those to
> > include handy information in plain ascii. But they may also include
> > arbitrary byte sequences.
> >
> > I think the simplest approach is to limit to isprint(c) && isascii(c)
> > and escape everything else.
> >
> > That means you can just cat the file and get something that looks OK.
> > Also, I'm trying to keep these files legal YAML, which requires them to
> > UTF-8, and this is a simple way to guarantee that.
>
> Two questions:
> - why can't be original function extended to cover this case
> (using additional flags, maybe)?
I found the ESCAPE_NP/"only" logic made it a little difficult to extend
string_escape_mem().
So, I wrote a patch series that removes the string_escape_mem flags that
aren't used, simplifies it a bit, then separates the flags into two
different types: those that select which characters to escape
(non-printable, non-ascii, whitespace, etc.) and those that choose a
style of escaping to use (octal, hex, or \\). That seems to make the
code a little easier to extend while still covering the cases people
actually use. I'll try to get those out this week and you can tell me
what you think.
> - where are the test cases?
I didn't write a test case. I agree that it would be a good idea--I'll
work on it.
--b.
next prev parent reply other threads:[~2019-08-06 18:50 UTC|newest]
Thread overview: 38+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-06-20 14:50 [PATCH 00/16] exposing knfsd client state to userspace J. Bruce Fields
2019-06-20 14:51 ` [PATCH 01/16] nfsd: persist nfsd filesystem across mounts J. Bruce Fields
2019-06-20 14:51 ` [PATCH 02/16] nfsd: rename cl_refcount J. Bruce Fields
2019-06-20 14:51 ` [PATCH 03/16] nfsd4: use reference count to free client J. Bruce Fields
2019-06-20 14:51 ` [PATCH 04/16] nfsd: add nfsd/clients directory J. Bruce Fields
2019-06-20 14:51 ` [PATCH 05/16] nfsd: make client/ directory names small ints J. Bruce Fields
2019-06-20 14:51 ` [PATCH 06/16] nfsd4: add a client info file J. Bruce Fields
2019-06-20 14:51 ` [PATCH 07/16] nfsd: copy client's address including port number to cl_addr J. Bruce Fields
2019-06-20 14:51 ` [PATCH 08/16] nfsd: escape high characters in binary data J. Bruce Fields
2019-06-21 17:45 ` J. Bruce Fields
2019-06-21 22:26 ` Kees Cook
2019-06-22 19:00 ` J. Bruce Fields
2019-06-22 20:22 ` Kees Cook
2019-06-24 21:05 ` J. Bruce Fields
2019-06-26 16:21 ` J. Bruce Fields
2019-06-27 4:16 ` Kees Cook
2019-06-27 15:23 ` J. Bruce Fields
2019-06-27 20:21 ` J. Bruce Fields
2019-06-28 3:58 ` Kees Cook
2019-06-28 16:33 ` J. Bruce Fields
2019-07-10 22:09 ` J. Bruce Fields
2019-07-11 1:54 ` Kees Cook
2019-08-06 12:19 ` Andy Shevchenko
2019-08-06 18:50 ` J. Bruce Fields [this message]
2019-08-07 9:00 ` Andy Shevchenko
2019-08-08 11:28 ` J. Bruce Fields
2019-08-27 13:36 ` Andy Shevchenko
2019-06-20 14:51 ` [PATCH 09/16] nfsd: add more information to client info file J. Bruce Fields
2019-06-20 14:51 ` [PATCH 10/16] nfsd4: add file to display list of client's opens J. Bruce Fields
2019-06-20 14:51 ` [PATCH 11/16] nfsd: show lock and deleg stateids J. Bruce Fields
2019-06-20 14:51 ` [PATCH 12/16] nfsd4: show layout stateids J. Bruce Fields
2019-06-20 14:51 ` [PATCH 13/16] nfsd: create get_nfsdfs_clp helper J. Bruce Fields
2019-06-20 14:51 ` [PATCH 14/16] nfsd: allow forced expiration of NFSv4 clients J. Bruce Fields
2019-06-20 14:51 ` [PATCH 15/16] nfsd: create xdr_netobj_dup helper J. Bruce Fields
2019-06-20 14:51 ` [PATCH 16/16] nfsd: decode implementation id J. Bruce Fields
2019-06-21 18:13 ` [PATCH 00/16] exposing knfsd client state to userspace J. Bruce Fields
2019-06-21 19:25 ` Anna Schumaker
2019-06-21 22:08 ` J. Bruce Fields
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=20190806185008.GC9456@parsley.fieldses.org \
--to=bfields@redhat.com \
--cc=andriy.shevchenko@intel.com \
--cc=linux-nfs@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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.