From: Eric Dumazet <eric.dumazet@gmail•com>
To: Christoph Paasch <cpaasch@apple•com>, David Miller <davem@davemloft•net>
Cc: netdev@vger•kernel.org
Subject: Re: [PATCH net] tcp md5sig: Use skb's saddr when replying to an incoming segment
Date: Mon, 11 Dec 2017 20:51:09 -0800 [thread overview]
Message-ID: <1513054269.25033.46.camel@gmail.com> (raw)
In-Reply-To: <20171211080546.89418-1-cpaasch@apple.com>
On Mon, 2017-12-11 at 00:05 -0800, Christoph Paasch wrote:
> The MD5-key that belongs to a connection is identified by the peer's
> IP-address. When we are in tcp_v4(6)_reqsk_send_ack(), we are
> replying
> to an incoming segment from tcp_check_req() that failed the seq-
> number
> checks.
>
> Thus, to find the correct key, we need to use the skb's saddr and not
> the daddr.
>
> This bug seems to have been there since quite a while, but probably
> got
> unnoticed because the consequences are not catastrophic. We will call
> tcp_v4_reqsk_send_ack only to send a challenge-ACK back to the peer,
> thus the connection doesn't really fail.
>
> Fixes: 9501f9722922 ("tcp md5sig: Let the caller pass appropriate key
> for tcp_v{4,6}_do_calc_md5_hash().")
> Signed-off-by: Christoph Paasch <cpaasch@apple•com>
> ---
> net/ipv4/tcp_ipv4.c | 2 +-
> net/ipv6/tcp_ipv6.c | 2 +-
> 2 files changed, 2 insertions(+), 2 deletions(-)
Reviewed-by: Eric Dumazet <edumazet@google•com>
Thanks !
next prev parent reply other threads:[~2017-12-12 4:51 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-12-11 8:05 [PATCH net] tcp md5sig: Use skb's saddr when replying to an incoming segment Christoph Paasch
2017-12-12 4:51 ` Eric Dumazet [this message]
2017-12-12 16:21 ` David 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=1513054269.25033.46.camel@gmail.com \
--to=eric.dumazet@gmail$(echo .)com \
--cc=cpaasch@apple$(echo .)com \
--cc=davem@davemloft$(echo .)net \
--cc=netdev@vger$(echo .)kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
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