Commit Graph

13 Commits

Author SHA1 Message Date
Xin Long
1fef8544bf sctp: remove the NETIF_F_SG flag before calling skb_segment
It makes more sense to clear NETIF_F_SG instead of set it when
calling skb_segment() in sctp_gso_segment(), since SCTP GSO is
using head_skb's fraglist, of which all frags are linear skbs.

This will make SCTP GSO code more understandable.

Suggested-by: Alexander Duyck <alexander.duyck@gmail.com>
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-01-16 19:05:59 -08:00
Xin Long
527beb8ef9 udp: support sctp over udp in skb_udp_tunnel_segment
For the gso of sctp over udp packets, sctp_gso_segment() will be called in
skb_udp_tunnel_segment(), we need to set transport_header to sctp header.

As all the current HWs can't handle both crc checksum and udp checksum at
the same time, the crc checksum has to be done in sctp_gso_segment() by
removing the NETIF_F_SCTP_CRC flag from the features.

Meanwhile, if the HW can't do udp checksum, csum and csum_start has to be
set correctly, and udp checksum will be done in __skb_udp_tunnel_segment()
by calling gso_make_checksum().

Thanks to Paolo, Marcelo and Guillaume for helping with this one.

v1->v2:
  - no change.
v2->v3:
  - remove the he NETIF_F_SCTP_CRC flag from the features.
  - set csum and csum_start in sctp_gso_make_checksum().

Signed-off-by: Xin Long <lucien.xin@gmail.com>
Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-10-30 15:23:46 -07:00
David S. Miller
a6cdeeb16b Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Some ISDN files that got removed in net-next had some changes
done in mainline, take the removals.

Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-07 11:00:14 -07:00
Matteo Croce
c3e933a5b8 sctp: deduplicate identical skb_checksum_ops
The same skb_checksum_ops struct is defined twice in two different places,
leading to code duplication. Declare it as a global variable into a common
header instead of allocating it on the stack on each function call.
bloat-o-meter reports a slight code shrink.

add/remove: 1/1 grow/shrink: 0/10 up/down: 128/-1282 (-1154)
Function                                     old     new   delta
sctp_csum_ops                                  -     128    +128
crc32c_csum_ops                               16       -     -16
sctp_rcv                                    6616    6583     -33
sctp_packet_pack                            4542    4504     -38
nf_conntrack_sctp_packet                    4980    4926     -54
execute_masked_set_action                   6453    6389     -64
tcf_csum_sctp                                575     428    -147
sctp_gso_segment                            1292    1126    -166
sctp_csum_check                              579     412    -167
sctp_snat_handler                            957     772    -185
sctp_dnat_handler                           1321    1132    -189
l4proto_manip_pkt                           2536    2313    -223
Total: Before=359297613, After=359296459, chg -0.00%

Reviewed-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: Matteo Croce <mcroce@redhat.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-05-30 14:35:44 -07:00
Thomas Gleixner
c942fddf87 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 157
Based on 3 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license as published by
  the free software foundation either version 2 of the license or at
  your option any later version this program is distributed in the
  hope that it will be useful but without any warranty without even
  the implied warranty of merchantability or fitness for a particular
  purpose see the gnu general public license for more details

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license as published by
  the free software foundation either version 2 of the license or at
  your option any later version [author] [kishon] [vijay] [abraham]
  [i] [kishon]@[ti] [com] this program is distributed in the hope that
  it will be useful but without any warranty without even the implied
  warranty of merchantability or fitness for a particular purpose see
  the gnu general public license for more details

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license as published by
  the free software foundation either version 2 of the license or at
  your option any later version [author] [graeme] [gregory]
  [gg]@[slimlogic] [co] [uk] [author] [kishon] [vijay] [abraham] [i]
  [kishon]@[ti] [com] [based] [on] [twl6030]_[usb] [c] [author] [hema]
  [hk] [hemahk]@[ti] [com] this program is distributed in the hope
  that it will be useful but without any warranty without even the
  implied warranty of merchantability or fitness for a particular
  purpose see the gnu general public license for more details

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 1105 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Richard Fontana <rfontana@redhat.com>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070033.202006027@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-30 11:26:37 -07:00
Xin Long
fc228abc23 sctp: call gso_reset_checksum when computing checksum in sctp_gso_segment
Jianlin reported a panic when running sctp gso over gre over vlan device:

  [   84.772930] RIP: 0010:do_csum+0x6d/0x170
  [   84.790605] Call Trace:
  [   84.791054]  csum_partial+0xd/0x20
  [   84.791657]  gre_gso_segment+0x2c3/0x390
  [   84.792364]  inet_gso_segment+0x161/0x3e0
  [   84.793071]  skb_mac_gso_segment+0xb8/0x120
  [   84.793846]  __skb_gso_segment+0x7e/0x180
  [   84.794581]  validate_xmit_skb+0x141/0x2e0
  [   84.795297]  __dev_queue_xmit+0x258/0x8f0
  [   84.795949]  ? eth_header+0x26/0xc0
  [   84.796581]  ip_finish_output2+0x196/0x430
  [   84.797295]  ? skb_gso_validate_network_len+0x11/0x80
  [   84.798183]  ? ip_finish_output+0x169/0x270
  [   84.798875]  ip_output+0x6c/0xe0
  [   84.799413]  ? ip_append_data.part.50+0xc0/0xc0
  [   84.800145]  iptunnel_xmit+0x144/0x1c0
  [   84.800814]  ip_tunnel_xmit+0x62d/0x930 [ip_tunnel]
  [   84.801699]  gre_tap_xmit+0xac/0xf0 [ip_gre]
  [   84.802395]  dev_hard_start_xmit+0xa5/0x210
  [   84.803086]  sch_direct_xmit+0x14f/0x340
  [   84.803733]  __dev_queue_xmit+0x799/0x8f0
  [   84.804472]  ip_finish_output2+0x2e0/0x430
  [   84.805255]  ? skb_gso_validate_network_len+0x11/0x80
  [   84.806154]  ip_output+0x6c/0xe0
  [   84.806721]  ? ip_append_data.part.50+0xc0/0xc0
  [   84.807516]  sctp_packet_transmit+0x716/0xa10 [sctp]
  [   84.808337]  sctp_outq_flush+0xd7/0x880 [sctp]

It was caused by SKB_GSO_CB(skb)->csum_start not set in sctp_gso_segment.
sctp_gso_segment() calls skb_segment() with 'feature | NETIF_F_HW_CSUM',
which causes SKB_GSO_CB(skb)->csum_start not to be set in skb_segment().

For TCP/UDP, when feature supports HW_CSUM, CHECKSUM_PARTIAL will be set
and gso_reset_checksum will be called to set SKB_GSO_CB(skb)->csum_start.

So SCTP should do the same as TCP/UDP, to call gso_reset_checksum() when
computing checksum in sctp_gso_segment.

Reported-by: Jianlin Shi <jishi@redhat.com>
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-02-13 19:31:43 -05:00
Daniel Axtens
1dd27cde30 net: use skb_is_gso_sctp() instead of open-coding
As well as the basic conversion, I noticed that a lot of the
SCTP code checks gso_type without first checking skb_is_gso()
so I have added that where appropriate.

Also, document the helper.

Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: Daniel Axtens <dja@axtens.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-03-09 11:41:47 -05:00
Willem de Bruijn
121d57af30 gso: validate gso_type in GSO handlers
Validate gso_type during segmentation as SKB_GSO_DODGY sources
may pass packets where the gso_type does not match the contents.

Syzkaller was able to enter the SCTP gso handler with a packet of
gso_type SKB_GSO_TCPV4.

On entry of transport layer gso handlers, verify that the gso_type
matches the transport protocol.

Fixes: 90017accff ("sctp: Add GSO support")
Link: http://lkml.kernel.org/r/<001a1137452496ffc305617e5fe0@google.com>
Reported-by: syzbot+fee64147a25aecd48055@syzkaller.appspotmail.com
Signed-off-by: Willem de Bruijn <willemb@google.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Reviewed-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-01-22 16:01:30 -05:00
Davide Caratti
dba003067a net: use skb->csum_not_inet to identify packets needing crc32c
skb->csum_not_inet carries the indication on which algorithm is needed to
compute checksum on skb in the transmit path, when skb->ip_summed is equal
to CHECKSUM_PARTIAL. If skb carries a SCTP packet and crc32c hasn't been
yet written in L4 header, skb->csum_not_inet is assigned to 1; otherwise,
assume Internet Checksum is needed and thus set skb->csum_not_inet to 0.

Suggested-by: Tom Herbert <tom@herbertland.com>
Signed-off-by: Davide Caratti <dcaratti@redhat.com>
Acked-by: Tom Herbert <tom@herbertland.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-05-19 19:21:29 -04:00
Davide Caratti
9617813dba skbuff: add stub to help computing crc32c on SCTP packets
sctp_compute_checksum requires crc32c symbol (provided by libcrc32c), so
it can't be used in net core. Like it has been done previously with other
symbols (e.g. ipv6_dst_lookup), introduce a stub struct skb_checksum_ops
to allow computation of crc32c checksum in net core after sctp.ko (and thus
libcrc32c) has been loaded.

Signed-off-by: Davide Caratti <dcaratti@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-05-19 19:21:29 -04:00
Xin Long
5207f39963 sctp: sctp gso should set feature with NETIF_F_SG when calling skb_segment
Now sctp gso puts segments into skb's frag_list, then processes these
segments in skb_segment. But skb_segment handles them only when gs is
enabled, as it's in the same branch with skb's frags.

Although almost all the NICs support sg other than some old ones, but
since commit 1e16aa3ddf ("net: gso: use feature flag argument in all
protocol gso handlers"), features &= skb->dev->hw_enc_features, and
xfrm_output_gso call skb_segment with features = 0, which means sctp
gso would call skb_segment with sg = 0, and skb_segment would not work
as expected.

This patch is to fix it by setting features param with NETIF_F_SG when
calling skb_segment so that it can go the right branch to process the
skb's frag_list.

Signed-off-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-01-25 12:28:33 -05:00
Marcelo Ricardo Leitner
c5c4e45c4b sctp: fix GSO for IPv6
commit 90017accff ("sctp: Add GSO support") didn't register SCTP GSO
offloading for IPv6 and yet didn't put any restrictions on generating
GSO packets while in IPv6, which causes all IPv6 GSO'ed packets to be
silently dropped.

The fix is to properly register the offload this time.

Fixes: 90017accff ("sctp: Add GSO support")
Signed-off-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-07-16 22:02:09 -07:00
Marcelo Ricardo Leitner
90017accff sctp: Add GSO support
SCTP has this pecualiarity that its packets cannot be just segmented to
(P)MTU. Its chunks must be contained in IP segments, padding respected.
So we can't just generate a big skb, set gso_size to the fragmentation
point and deliver it to IP layer.

This patch takes a different approach. SCTP will now build a skb as it
would be if it was received using GRO. That is, there will be a cover
skb with protocol headers and children ones containing the actual
segments, already segmented to a way that respects SCTP RFCs.

With that, we can tell skb_segment() to just split based on frag_list,
trusting its sizes are already in accordance.

This way SCTP can benefit from GSO and instead of passing several
packets through the stack, it can pass a single large packet.

v2:
- Added support for receiving GSO frames, as requested by Dave Miller.
- Clear skb->cb if packet is GSO (otherwise it's not used by SCTP)
- Added heuristics similar to what we have in TCP for not generating
  single GSO packets that fills cwnd.
v3:
- consider sctphdr size in skb_gso_transport_seglen()
- rebased due to 5c7cdf339a ("gso: Remove arbitrary checks for
  unsupported GSO")

Signed-off-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Tested-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-06-03 19:37:21 -04:00