From: "David S. Miller" <davem@redhat.com>
To: "David S. Miller" <davem@redhat.com>
Cc: herbert@gondor.apana.org.au, netdev@oss.sgi.com
Subject: Re: [ROUTE] PMTU only works on half the time
Date: Mon, 1 Dec 2003 15:22:15 -0800 [thread overview]
Message-ID: <20031201152215.522c2447.davem@redhat.com> (raw)
In-Reply-To: <20031201142131.5da50a07.davem@redhat.com>
On Mon, 1 Dec 2003 14:21:31 -0800
"David S. Miller" <davem@redhat.com> wrote:
> Let me think about this some more, maybe you're right and the
> error exists in both of these places.
Ok, I did my thinking :)
rt->rt_src is special. It is the source address we have selected
to use with this route. All output packets using this route must
use rt->rt_src as iph->saddr.
So, in effect, when we say "if (rt->rt_src == iph->saddr)" we
are asking the question "did we make this packet?" I think this
is why Alexey coded the test in this way.
You are speaking of a case of zero source addresses. When would
we output such an iph->saddr, by way of a route? Right now this
is the only part I'm not seeing.
I want to be careful in changing this code, as loosening the key check
opens the possibility of new kinds of PMTU lowering attacks.
next prev parent reply other threads:[~2003-12-01 23:22 UTC|newest]
Thread overview: 23+ messages / expand[flat|nested] mbox.gz Atom feed top
2003-12-01 20:16 [ROUTE] PMTU only works on half the time Herbert Xu
2003-12-01 20:47 ` Herbert Xu
2003-12-01 21:51 ` David S. Miller
2003-12-01 22:05 ` Herbert Xu
2003-12-01 22:21 ` David S. Miller
2003-12-01 23:22 ` David S. Miller [this message]
2003-12-02 10:10 ` Herbert Xu
2003-12-02 10:27 ` David S. Miller
2003-12-02 10:33 ` Herbert Xu
2003-12-01 23:30 ` Julian Anastasov
2003-12-01 23:50 ` David S. Miller
2003-12-02 0:04 ` Julian Anastasov
2003-12-02 0:07 ` Julian Anastasov
2003-12-02 0:08 ` David S. Miller
2003-12-02 1:53 ` Julian Anastasov
2003-12-02 23:40 ` Julian Anastasov
2003-12-03 0:07 ` David S. Miller
2003-12-03 0:39 ` David S. Miller
2003-12-03 1:43 ` Julian Anastasov
2003-12-03 22:03 ` Julian Anastasov
2003-12-05 20:43 ` David S. Miller
2003-12-06 7:52 ` Julian Anastasov
2003-12-10 23:15 ` David S. Miller
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=20031201152215.522c2447.davem@redhat.com \
--to=davem@redhat.com \
--cc=herbert@gondor.apana.org.au \
--cc=netdev@oss.sgi.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).