mirror of https://lore.kernel.org/lkml/
 help / color / mirror / Atom feed
From: Jens Axboe <axboe@kernel.dk>
To: Al Viro <viro@zeniv.linux.org.uk>
Cc: "Jason A. Donenfeld" <Jason@zx2c4.com>,
	Theodore Ts'o <tytso@mit.edu>, Christoph Hellwig <hch@lst.de>,
	LKML <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH v4 0/3] random: convert to using iters, for Al Viro
Date: Fri, 20 May 2022 09:53:30 -0600	[thread overview]
Message-ID: <7e78d6a7-1cc3-2408-fe91-0329f5020e77@kernel.dk> (raw)
In-Reply-To: <Yoe4HP9iTA6l/For@zeniv-ca.linux.org.uk>

On 5/20/22 9:47 AM, Al Viro wrote:
> On Fri, May 20, 2022 at 09:34:46AM -0600, Jens Axboe wrote:
> 
>> I'm very sure, otherwise we're just accepting that we're breaking real
>> world applications.
> 
> "Breaking" as in "it used to work with earlier kernels, doesn't work with
> recent ones"?  Details, please...

Yes, as in exactly that. This is what drove this addition of
->read_iter() for urandom. See commit:

ommit 36e2c7421f02a22f71c9283e55fdb672a9eb58e7
Author: Christoph Hellwig <hch@lst.de>
Date:   Thu Sep 3 16:22:34 2020 +0200

    fs: don't allow splice read/write without explicit ops

related to the set_fs() changes, and now go look for any commit that
has:

Fixes: 36e2c7421f02 ("fs: don't allow splice read/write without explicit ops")

in it and see that this isn't an isolated incident at all.

tldr - splice from /dev/urandom used to work, and I recently got a
report internally on an application that broke on upgrade from 5.6 to
5.12 exactly because it now just just -EINVAL's instead.

-- 
Jens Axboe


  reply	other threads:[~2022-05-20 15:53 UTC|newest]

Thread overview: 28+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2022-05-20  9:44 Jason A. Donenfeld
2022-05-20  9:44 ` [PATCH v4 1/3] random: convert to using fops->read_iter() Jason A. Donenfeld
2022-05-20 13:37   ` Jason A. Donenfeld
2022-05-20 14:36     ` Jens Axboe
2022-05-20 14:39       ` Jason A. Donenfeld
2022-05-20 15:12         ` Al Viro
2022-05-20  9:44 ` [PATCH v4 2/3] random: convert to using fops->write_iter() Jason A. Donenfeld
2022-05-20  9:44 ` [PATCH v4 3/3] random: wire up fops->splice_{read,write}_iter() Jason A. Donenfeld
2022-05-20 12:16 ` [PATCH v4 0/3] random: convert to using iters, for Al Viro Jens Axboe
2022-05-20 15:25 ` Jason A. Donenfeld
2022-05-20 15:34   ` Jens Axboe
2022-05-20 15:39     ` Jason A. Donenfeld
2022-05-20 15:44       ` Jens Axboe
2022-05-20 15:55         ` Jason A. Donenfeld
2022-05-20 15:58           ` Jens Axboe
2022-05-20 16:03             ` Jason A. Donenfeld
2022-05-20 16:06               ` Jens Axboe
2022-05-20 15:46     ` Jason A. Donenfeld
2022-05-20 15:51       ` Jens Axboe
2022-05-20 15:58         ` Jason A. Donenfeld
2022-05-20 16:00           ` Jens Axboe
2022-05-20 15:47     ` Al Viro
2022-05-20 15:53       ` Jens Axboe [this message]
2022-05-20 16:15         ` Al Viro
2022-05-20 16:24           ` Jens Axboe
2022-05-20 16:39             ` Jason A. Donenfeld
2022-05-20 16:41               ` Jens Axboe
2022-05-24  4:52                 ` Eric W. Biederman

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=7e78d6a7-1cc3-2408-fe91-0329f5020e77@kernel.dk \
    --to=axboe@kernel.dk \
    --cc=Jason@zx2c4.com \
    --cc=hch@lst.de \
    --cc=linux-kernel@vger.kernel.org \
    --cc=tytso@mit.edu \
    --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

Powered by JetHome