From: Xin Long <lucien.xin@gmail.com>
To: Willem de Bruijn <willemdebruijn.kernel@gmail.com>
Cc: network dev <netdev@vger.kernel.org>,
linux-sctp@vger.kernel.org,
Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>,
Neil Horman <nhorman@tuxdriver.com>,
Michael Tuexen <tuexen@fh-muenster.de>,
David Miller <davem@davemloft.net>
Subject: Re: [PATCHv2 net-next 02/17] udp6: move the mss check after udp gso tunnel processing
Date: Fri, 09 Oct 2020 01:48:45 +0000 [thread overview]
Message-ID: <CADvbK_en7mePKdmMaLr9V8hTdmjf2bSVpSrid2CjharJtvD6YQ@mail.gmail.com> (raw)
In-Reply-To: <CA+FuTScNHkYu2F2xPBjLj9ivfLRXVbTPypgjvtEZrebatpJJfQ@mail.gmail.com>
On Thu, Oct 8, 2020 at 8:45 PM Willem de Bruijn
<willemdebruijn.kernel@gmail.com> wrote:
>
> On Thu, Oct 8, 2020 at 5:48 AM Xin Long <lucien.xin@gmail.com> wrote:
> >
> > For some protocol's gso, like SCTP, it's using GSO_BY_FRAGS for
> > gso_size. When using UDP to encapsulate its packet, it will
> > return error in udp6_ufo_fragment() as skb->len < gso_size,
> > and it will never go to the gso tunnel processing.
> >
> > So we should move this check after udp gso tunnel processing,
> > the same as udp4_ufo_fragment() does. While at it, also tidy
> > the variables up.
>
> Please don't mix a new feature and code cleanup.
Hi, Willem,
Tidying up variables are not worth a single patch, that's what I was
thinking. I can leave the variables as it is if you wish in this patch.
>
> This patch changes almost every line of the function due to
> indentation changes. But the only relevant part is
>
> "
> mss = skb_shinfo(skb)->gso_size;
> if (unlikely(skb->len <= mss))
> goto out;
>
> if (skb->encapsulation && skb_shinfo(skb)->gso_type &
> (SKB_GSO_UDP_TUNNEL|SKB_GSO_UDP_TUNNEL_CSUM))
> segs = skb_udp_tunnel_segment(skb, features, true);
> else {
> /* irrelevant here */
> }
>
> out:
> return segs;
> }
> "
>
> Is it a sufficient change to just skip the mss check if mss = GSO_BY_FRAGS?
It is sufficient.
But I think we'd better keep the code here consistent with ipv4's if
there's no other reason to do 'skb->len <= mss' check at the first.
We can go with if-else as you showed above now, then do a cleanup in
the future. What do you think?
WARNING: multiple messages have this Message-ID (diff)
From: Xin Long <lucien.xin@gmail.com>
To: Willem de Bruijn <willemdebruijn.kernel@gmail.com>
Cc: network dev <netdev@vger.kernel.org>,
linux-sctp@vger.kernel.org,
Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>,
Neil Horman <nhorman@tuxdriver.com>,
Michael Tuexen <tuexen@fh-muenster.de>,
David Miller <davem@davemloft.net>
Subject: Re: [PATCHv2 net-next 02/17] udp6: move the mss check after udp gso tunnel processing
Date: Fri, 9 Oct 2020 09:48:45 +0800 [thread overview]
Message-ID: <CADvbK_en7mePKdmMaLr9V8hTdmjf2bSVpSrid2CjharJtvD6YQ@mail.gmail.com> (raw)
Message-ID: <20201009014845.waI785LS_eGWP9zQFceba-TF1MbawKNC69iSzcpmnoI@z> (raw)
In-Reply-To: <CA+FuTScNHkYu2F2xPBjLj9ivfLRXVbTPypgjvtEZrebatpJJfQ@mail.gmail.com>
On Thu, Oct 8, 2020 at 8:45 PM Willem de Bruijn
<willemdebruijn.kernel@gmail.com> wrote:
>
> On Thu, Oct 8, 2020 at 5:48 AM Xin Long <lucien.xin@gmail.com> wrote:
> >
> > For some protocol's gso, like SCTP, it's using GSO_BY_FRAGS for
> > gso_size. When using UDP to encapsulate its packet, it will
> > return error in udp6_ufo_fragment() as skb->len < gso_size,
> > and it will never go to the gso tunnel processing.
> >
> > So we should move this check after udp gso tunnel processing,
> > the same as udp4_ufo_fragment() does. While at it, also tidy
> > the variables up.
>
> Please don't mix a new feature and code cleanup.
Hi, Willem,
Tidying up variables are not worth a single patch, that's what I was
thinking. I can leave the variables as it is if you wish in this patch.
>
> This patch changes almost every line of the function due to
> indentation changes. But the only relevant part is
>
> "
> mss = skb_shinfo(skb)->gso_size;
> if (unlikely(skb->len <= mss))
> goto out;
>
> if (skb->encapsulation && skb_shinfo(skb)->gso_type &
> (SKB_GSO_UDP_TUNNEL|SKB_GSO_UDP_TUNNEL_CSUM))
> segs = skb_udp_tunnel_segment(skb, features, true);
> else {
> /* irrelevant here */
> }
>
> out:
> return segs;
> }
> "
>
> Is it a sufficient change to just skip the mss check if mss == GSO_BY_FRAGS?
It is sufficient.
But I think we'd better keep the code here consistent with ipv4's if
there's no other reason to do 'skb->len <= mss' check at the first.
We can go with if-else as you showed above now, then do a cleanup in
the future. What do you think?
next prev parent reply other threads:[~2020-10-09 1:48 UTC|newest]
Thread overview: 62+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-10-08 9:47 [PATCHv2 net-next 00/17] sctp: Implement RFC6951: UDP Encapsulation of SCTP Xin Long
2020-10-08 9:47 ` Xin Long
2020-10-08 9:47 ` [PATCHv2 net-next 01/17] udp: check udp sock encap_type in __udp_lib_err Xin Long
2020-10-08 9:47 ` Xin Long
2020-10-08 9:47 ` [PATCHv2 net-next 02/17] udp6: move the mss check after udp gso tunnel processing Xin Long
2020-10-08 9:47 ` Xin Long
2020-10-08 9:47 ` [PATCHv2 net-next 03/17] udp: do checksum properly in skb_udp_tunnel_segment Xin Long
2020-10-08 9:47 ` Xin Long
2020-10-08 9:48 ` [PATCHv2 net-next 04/17] udp: support sctp over udp " Xin Long
2020-10-08 9:48 ` Xin Long
2020-10-08 9:48 ` [PATCHv2 net-next 05/17] sctp: create udp4 sock and add its encap_rcv Xin Long
2020-10-08 9:48 ` Xin Long
2020-10-08 9:48 ` [PATCHv2 net-next 06/17] sctp: create udp6 sock and set " Xin Long
2020-10-08 9:48 ` Xin Long
2020-10-08 9:48 ` [PATCHv2 net-next 07/17] sctp: add encap_err_lookup for udp encap socks Xin Long
2020-10-08 9:48 ` Xin Long
2020-10-08 9:48 ` [PATCHv2 net-next 08/17] sctp: add encap_port for netns sock asoc and transport Xin Long
2020-10-08 9:48 ` Xin Long
2020-10-08 9:48 ` [PATCHv2 net-next 09/17] sctp: add SCTP_REMOTE_UDP_ENCAPS_PORT sockopt Xin Long
2020-10-08 9:48 ` Xin Long
2020-10-08 9:48 ` [PATCHv2 net-next 10/17] sctp: allow changing transport encap_port by peer packets Xin Long
2020-10-08 9:48 ` Xin Long
2020-10-08 9:48 ` [PATCHv2 net-next 11/17] sctp: add udphdr to overhead when udp_port is set Xin Long
2020-10-08 9:48 ` Xin Long
2020-10-08 9:48 ` [PATCHv2 net-next 12/17] sctp: call sk_setup_caps in sctp_packet_transmit instead Xin Long
2020-10-08 9:48 ` Xin Long
2020-10-08 9:48 ` [PATCHv2 net-next 13/17] sctp: support for sending packet over udp4 sock Xin Long
2020-10-08 9:48 ` Xin Long
2020-10-08 9:48 ` [PATCHv2 net-next 14/17] sctp: support for sending packet over udp6 sock Xin Long
2020-10-08 9:48 ` Xin Long
2020-10-08 9:48 ` [PATCHv2 net-next 15/17] sctp: add the error cause for new encapsulation port restart Xin Long
2020-10-08 9:48 ` Xin Long
2020-10-08 9:48 ` [PATCHv2 net-next 16/17] sctp: handle the init chunk matching an existing asoc Xin Long
2020-10-08 9:48 ` Xin Long
2020-10-08 9:48 ` [PATCHv2 net-next 17/17] sctp: enable udp tunneling socks Xin Long
2020-10-08 9:48 ` Xin Long
2020-10-08 15:46 ` kernel test robot
2020-10-08 15:46 ` kernel test robot
2020-10-09 2:02 ` Xin Long
2020-10-09 2:02 ` Xin Long
2020-10-08 14:33 ` [PATCHv2 net-next 15/17] sctp: add the error cause for new encapsulation port restart kernel test robot
2020-10-08 14:33 ` kernel test robot
2020-10-08 13:10 ` [PATCHv2 net-next 09/17] sctp: add SCTP_REMOTE_UDP_ENCAPS_PORT sockopt kernel test robot
2020-10-08 13:10 ` kernel test robot
2020-10-08 21:18 ` [PATCHv2 net-next 06/17] sctp: create udp6 sock and set its encap_rcv kernel test robot
2020-10-08 21:18 ` kernel test robot
2020-10-09 1:59 ` Xin Long
2020-10-09 1:59 ` Xin Long
2020-10-08 18:29 ` [PATCHv2 net-next 05/17] sctp: create udp4 sock and add " kernel test robot
2020-10-08 18:29 ` kernel test robot
2020-10-09 1:59 ` Xin Long
2020-10-09 1:59 ` Xin Long
2020-10-08 10:01 ` [PATCHv2 net-next 04/17] udp: support sctp over udp in skb_udp_tunnel_segment Xin Long
2020-10-08 10:01 ` Xin Long
2020-10-08 10:01 ` [PATCHv2 net-next 03/17] udp: do checksum properly " Xin Long
2020-10-08 10:01 ` Xin Long
2020-10-08 12:44 ` [PATCHv2 net-next 02/17] udp6: move the mss check after udp gso tunnel processing Willem de Bruijn
2020-10-08 12:44 ` Willem de Bruijn
2020-10-09 1:48 ` Xin Long [this message]
2020-10-09 1:48 ` Xin Long
2020-10-09 13:59 ` Willem de Bruijn
2020-10-09 13:59 ` Willem de Bruijn
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=CADvbK_en7mePKdmMaLr9V8hTdmjf2bSVpSrid2CjharJtvD6YQ@mail.gmail.com \
--to=lucien.xin@gmail.com \
--cc=davem@davemloft.net \
--cc=linux-sctp@vger.kernel.org \
--cc=marcelo.leitner@gmail.com \
--cc=netdev@vger.kernel.org \
--cc=nhorman@tuxdriver.com \
--cc=tuexen@fh-muenster.de \
--cc=willemdebruijn.kernel@gmail.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).