mirror of https://lore.kernel.org/lkml/
 help / color / mirror / Atom feed
From: 岡嶋 寿行 <toshi.okajima@jp.fujitsu.com>
To: "David Howells" <dhowells@redhat.com>
Cc: "Toshiyuki Okajima" <toshi.okajima@jp.fujitsu.com>,
	dhowells@redhat.com, keyrings@linux-nfs.org, security@kernel.org,
	linux-security-module@vger.kernel.org,
	linux-kernel@vger.kernel.org
Subject: Re: [PATCH 1/1][BUG][TAKE2] KEYRINGS: find_keyring_by_name() can gain the freed keyring
Date: Sat, 24 Apr 2010 09:32:54 +0900 (JST)	[thread overview]
Message-ID: <50d28d42d9f97dd6444c54265de9cd4b.squirrel@webmail-b.css.fujitsu.com> (raw)
In-Reply-To: <1790.1272037936@redhat.com>

> Toshiyuki Okajima <toshi.okajima@jp.fujitsu.com> wrote:
>
>> > Better still, atomic_inc_not_zero().  How about the attached patch?
>> Your fix looks good to me. But, if usage count of the keyring is 0,
>> I think it better to return -ENOKEY immediately.
>

> The problem with that is that someone else may have created a keyring with
> the
> same name that you can't then reach until the dead keyring is deleted.

OK. I understand.
---
Once find_keyring_by_name() returns -ENOKEY, the new user creates a
new key. So, both the deleting key and the new key may exist.
Therefore at next find_keyring_by_name() call, we should find the new
key and ignore the deleting key.
---

Toshiyuki Okajima


  reply	other threads:[~2010-04-24  0:32 UTC|newest]

Thread overview: 13+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2010-04-22  7:37 [PATCH 1/1][BUG][IMPORTANT] " Toshiyuki Okajima
2010-04-22 10:16 ` David Howells
2010-04-23 10:45   ` Toshiyuki Okajima
2010-04-23 10:51     ` [PATCH 1/1][BUG][TAKE2] " Toshiyuki Okajima
2010-04-23 11:33     ` David Howells
2010-04-23 15:23       ` Toshiyuki Okajima
2010-04-23 15:52       ` David Howells
2010-04-24  0:32         ` 岡嶋 寿行 [this message]
2010-04-26 14:22         ` Toshiyuki Okajima
2010-04-26 14:47         ` David Howells
2010-04-26 10:57       ` David Howells
2010-04-26 14:42         ` Toshiyuki Okajima
2010-04-29 11:23           ` Toshiyuki Okajima

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=50d28d42d9f97dd6444c54265de9cd4b.squirrel@webmail-b.css.fujitsu.com \
    --to=toshi.okajima@jp.fujitsu.com \
    --cc=dhowells@redhat.com \
    --cc=keyrings@linux-nfs.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-security-module@vger.kernel.org \
    --cc=security@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 a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox

Powered by JetHome