From: Thomas Graf <tgraf@suug.ch>
To: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Cc: netdev <netdev@vger.kernel.org>,
Eric Dumazet <eric.dumazet@gmail.com>,
Herbert Xu <herbert@gondor.apana.org.au>,
Stable <stable@vger.kernel.org>,
David Miller <davem@davemloft.net>
Subject: Re: [PATCH v3.17 .. v3.19] lib/rhashtable: fix race between rhashtable_lookup_compare and hashtable resize
Date: Tue, 30 Jun 2015 08:28:36 +0200 [thread overview]
Message-ID: <20150630062836.GQ14658@pox.localdomain> (raw)
In-Reply-To: <20150626104817.16520.77222.stgit@buzz>
On 06/26/15 at 01:48pm, Konstantin Khlebnikov wrote:
> Hash value passed as argument into rhashtable_lookup_compare could be
> computed using different hash table than rhashtable_lookup_compare sees.
>
> This patch passes key into rhashtable_lookup_compare() instead of hash and
> compures hash value right in place using the same table as for lookup.
>
> Also it adds comment for rhashtable_hashfn and rhashtable_obj_hashfn:
> user must prevent concurrent insert/remove otherwise returned hash value
> could be invalid.
>
> Signed-off-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
> Fixes: e341694e3eb5 ("netlink: Convert netlink_lookup() to use RCU protected hash table")
> Link: http://lkml.kernel.org/r/20150514042151.GA5482@gondor.apana.org.au
> Cc: Stable <stable@vger.kernel.org> (v3.17 .. v3.19)
Nice catch.
For reference, this is a partial cherry pick of
8d24c0b43125e ("rhashtable: Do hashing inside of rhashtable_lookup_compare()")
nft_hash is not affected as it doesn't use the lookup API until 4.0.
Acked-by: Thomas Graf <tgraf@suug.ch>
next prev parent reply other threads:[~2015-06-30 6:28 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-06-26 10:48 [PATCH v3.17 .. v3.19] lib/rhashtable: fix race between rhashtable_lookup_compare and hashtable resize Konstantin Khlebnikov
2015-06-27 7:07 ` Herbert Xu
2015-06-30 6:28 ` Thomas Graf [this message]
2015-06-30 9:39 ` Konstantin Khlebnikov
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=20150630062836.GQ14658@pox.localdomain \
--to=tgraf@suug.ch \
--cc=davem@davemloft.net \
--cc=eric.dumazet@gmail.com \
--cc=herbert@gondor.apana.org.au \
--cc=khlebnikov@yandex-team.ru \
--cc=netdev@vger.kernel.org \
--cc=stable@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 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).