From: Pablo Neira Ayuso <pablo@netfilter.org>
To: Phil Oester <kernel@linuxace.com>
Cc: netfilter-devel@vger.kernel.org
Subject: Re: [PATCH] Remove redundant TCP header checks from xt_TCPOPTSTRIP
Date: Mon, 10 Jun 2013 20:15:16 +0200 [thread overview]
Message-ID: <20130610181516.GA3757@localhost> (raw)
In-Reply-To: <20130610035948.GA2742@gmail.com>
On Sun, Jun 09, 2013 at 11:59:48PM -0400, Phil Oester wrote:
> In commit bc6bcb59 ("netfilter: xt_TCPOPTSTRIP: fix possible mangling beyond
> packet boundary"), a check for short TCP header or malformed packet was added.
> This check is unnecessary, as these packets are already handled in the tcp_error
> function of nf_conntrack_proto_tcp.c (see /* Not whole TCP header or malformed
> packet */).
We cannot assume nf_conntrack is loaded. We have to support stateless
setups as well.
> In addition, there was an error in the check which was added (len
> is being calculated incorrectly). In my testing, ALL packets are being dropped
> by the TCPOPTSTRIP target at present. Revert the unnecessary/incorrect checks.
Then, we have to fix the wrong calculation. I cannot reproduce this
here.
next prev parent reply other threads:[~2013-06-10 18:15 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-06-10 3:59 [PATCH] Remove redundant TCP header checks from xt_TCPOPTSTRIP Phil Oester
2013-06-10 18:15 ` Pablo Neira Ayuso [this message]
2013-06-10 20:22 ` Florian Westphal
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=20130610181516.GA3757@localhost \
--to=pablo@netfilter.org \
--cc=kernel@linuxace.com \
--cc=netfilter-devel@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).