From: David Howells <dhowells@redhat.com>
To: Jeff Layton <jlayton@redhat.com>
Cc: dhowells@redhat.com, steved@redhat.com, jmorris@namei.org,
linux-security-module@vger.kernel.org, keyrings@linux-nfs.org,
linux-nfs@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [Keyrings] [PATCH 7/9] KEYS: Permit in-place link replacement in keyring list
Date: Mon, 19 Mar 2012 15:39:00 +0000 [thread overview]
Message-ID: <14790.1332171540@redhat.com> (raw)
In-Reply-To: <20120319104432.56fe1e66@redhat.com>
Jeff Layton <jlayton@redhat.com> wrote:
> Why is it safe to use key_put(rcu_access_pointer(...)) ? Clearly that
> pointer will end up being dereferenced, right?
Simple. This key_put() is called from within keyring_destroy() and that is
only ever called from the garbage collector - which is non-reentrant. Add to
that that key_put() never actually destroys a now-unused key, but merely
schedules the gc for a future run, and it's *that* that searches out unused
keys and deletes them.
David
next prev parent reply other threads:[~2012-03-19 15:39 UTC|newest]
Thread overview: 12+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-02-08 11:02 [PATCH 1/9] KEYS: Allow special keyrings to be cleared David Howells
2012-02-08 11:03 ` [PATCH 2/9] keys: update the description with info about "logon" keys David Howells
2012-02-08 11:03 ` [PATCH 3/9] KEYS: Move the key config into security/keys/Kconfig David Howells
2012-02-08 11:03 ` [PATCH 4/9] KEYS: Reorganise keys Makefile David Howells
2012-02-08 11:03 ` [PATCH 5/9] KEYS: Announce key type (un)registration David Howells
2012-02-08 11:03 ` [PATCH 6/9] KEYS: Perform RCU synchronisation on keys prior to key destruction David Howells
2012-03-19 14:31 ` [Keyrings] " Jeff Layton
2012-02-08 11:04 ` [PATCH 7/9] KEYS: Permit in-place link replacement in keyring list David Howells
2012-03-19 14:44 ` [Keyrings] " Jeff Layton
2012-03-19 15:39 ` David Howells [this message]
2012-02-08 11:04 ` [PATCH 8/9] KEYS: Do LRU discard in full keyrings David Howells
2012-02-08 11:04 ` [PATCH 9/9] KEYS: Add invalidation support David Howells
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=14790.1332171540@redhat.com \
--to=dhowells@redhat.com \
--cc=jlayton@redhat.com \
--cc=jmorris@namei.org \
--cc=keyrings@linux-nfs.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-nfs@vger.kernel.org \
--cc=linux-security-module@vger.kernel.org \
--cc=steved@redhat.com \
/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).