All of lore.kernel.org
 help / color / mirror / Atom feed
From: Jens Axboe <axboe@kernel.dk>
To: Pavel Begunkov <asml.silence@gmail.com>,
	linux-block@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [BUG] io_uring: defer logic based on shared data
Date: Fri, 25 Oct 2019 10:09:41 -0600	[thread overview]
Message-ID: <dfd21591-5187-0a8b-cc55-cfe5d57dd471@kernel.dk> (raw)
In-Reply-To: <bfb58429-6abe-06f0-3fd8-14a0040cecf0@kernel.dk>

On 10/25/19 10:03 AM, Jens Axboe wrote:
> On 10/25/19 3:55 AM, Pavel Begunkov wrote:
>> I found 2 problems with __io_sequence_defer().
>>
>> 1. it uses @sq_dropped, but doesn't consider @cq_overflow
>> 2. @sq_dropped and @cq_overflow are write-shared with userspace, so
>> it can be maliciously changed.
>>
>> see sent liburing test (test/defer *_hung()), which left an unkillable
>> process for me
> 
> OK, how about the below. I'll split this in two, as it's really two
> separate fixes.

Patch 1:

http://git.kernel.dk/cgit/linux-block/commit/?h=for-linus&id=9a9a21d9cf65cb621cce4052a4527868a80009ad

and patch 2:

http://git.kernel.dk/cgit/linux-block/commit/?h=for-linus&id=ed348662f74c4f63537b3c188585e39cdea22713

Let me know what you think, and if/when I can add your reviewed/test-by
to them.

-- 
Jens Axboe


  reply	other threads:[~2019-10-25 16:09 UTC|newest]

Thread overview: 13+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-10-25  9:55 [BUG] io_uring: defer logic based on shared data Pavel Begunkov
2019-10-25 16:03 ` Jens Axboe
2019-10-25 16:09   ` Jens Axboe [this message]
2019-10-25 16:21     ` Jens Axboe
2019-10-25 16:21   ` Pavel Begunkov
2019-10-25 16:27     ` Jens Axboe
2019-10-25 16:32       ` Jens Axboe
2019-10-25 16:40         ` Pavel Begunkov
2019-10-25 16:44           ` Jens Axboe
2019-10-25 16:55             ` Pavel Begunkov
2019-10-25 16:57               ` Jens Axboe
2019-10-25 18:13                 ` Pavel Begunkov
2019-10-25 18:17                   ` Jens Axboe

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=dfd21591-5187-0a8b-cc55-cfe5d57dd471@kernel.dk \
    --to=axboe@kernel.dk \
    --cc=asml.silence@gmail.com \
    --cc=linux-block@vger.kernel.org \
    --cc=linux-kernel@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.