60 Commits
Author SHA1 Message Date
Qi TangandSteffen Klassert 1c428b0384 xfrm: hold dev ref until after transport_finish NF_HOOK
After async crypto completes, xfrm_input_resume() calls dev_put()
immediately on re-entry before the skb reaches transport_finish.
The skb->dev pointer is then used inside NF_HOOK and its okfn,
which can race with device teardown.

Remove the dev_put from the async resumption entry and instead
drop the reference after the NF_HOOK call in transport_finish,
using a saved device pointer since NF_HOOK may consume the skb.
This covers NF_DROP, NF_QUEUE and NF_STOLEN paths that skip
the okfn.

For non-transport exits (decaps, gro, drop) and secondary
async return points, release the reference inline when
async is set.

Suggested-by: Florian Westphal <fw@strlen.de>
Fixes: acf568ee85 ("xfrm: Reinject transport-mode packets through tasklet")
Cc: stable@vger.kernel.org
Signed-off-by: Qi Tang <tpluszz77@gmail.com>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
2026-04-07 10:12:40 +02:00
Tobias BrunnerandSteffen Klassert 3ac9e29211 xfrm: Set transport header to fix UDP GRO handling
The referenced commit replaced a call to __xfrm4|6_udp_encap_rcv() with
a custom check for non-ESP markers.  But what the called function also
did was setting the transport header to the ESP header.  The function
that follows, esp4|6_gro_receive(), relies on that being set when it calls
xfrm_parse_spi().  We have to set the full offset as the skb's head was
not moved yet so adding just the UDP header length won't work.

Fixes: e3fd057776 ("xfrm: Fix UDP GRO handling for some corner cases")
Signed-off-by: Tobias Brunner <tobias@strongswan.org>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
2025-07-02 09:19:56 +02:00
Tobias BrunnerandSteffen Klassert e3fd057776 xfrm: Fix UDP GRO handling for some corner cases
This fixes an issue that's caused if there is a mismatch between the data
offset in the GRO header and the length fields in the regular sk_buff due
to the pskb_pull()/skb_push() calls.  That's because the UDP GRO layer
stripped off the UDP header via skb_gro_pull() already while the UDP
header was explicitly not pulled/pushed in this function.

For example, an IKE packet that triggered this had len=data_len=1268 and
the data_offset in the GRO header was 28 (IPv4 + UDP).  So pskb_pull()
was called with an offset of 28-8=20, which reduced len to 1248 and via
pskb_may_pull() and __pskb_pull_tail() it also set data_len to 1248.
As the ESP offload module was not loaded, the function bailed out and
called skb_push(), which restored len to 1268, however, data_len remained
at 1248.

So while skb_headlen() was 0 before, it was now 20.  The latter caused a
difference of 8 instead of 28 (or 0 if pskb_pull()/skb_push() was called
with the complete GRO data_offset) in gro_try_pull_from_frag0() that
triggered a call to gro_pull_from_frag0() that corrupted the packet.

This change uses a more GRO-like approach seen in other GRO receivers
via skb_gro_header() to just read the actual data we are interested in
and does not try to "restore" the UDP header at this point to call the
existing function.  If the offload module is not loaded, it immediately
bails out, otherwise, it only does a quick check to see if the packet
is an IKE or keepalive packet instead of calling the existing function.

Fixes: 172bf009c1 ("xfrm: Support GRO for IPv4 ESP in UDP encapsulation")
Fixes: 221ddb723d ("xfrm: Support GRO for IPv6 ESP in UDP encapsulation")
Signed-off-by: Tobias Brunner <tobias@strongswan.org>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
2025-04-17 11:08:16 +02:00
Guillaume NaultandJakub Kicinski 66fb6386d3 ipv4: Convert ip_route_input_noref() to dscp_t.
Pass a dscp_t variable to ip_route_input_noref(), instead of a plain
u8, to prevent accidental setting of ECN bits in ->flowi4_tos.

Callers of ip_route_input_noref() to consider are:

  * arp_process() in net/ipv4/arp.c. This function sets the tos
    parameter to 0, which is already a valid dscp_t value, so it
    doesn't need to be adjusted for the new prototype.

  * ip_route_input(), which already has a dscp_t variable to pass as
    parameter. We just need to remove the inet_dscp_to_dsfield()
    conversion.

  * ipvlan_l3_rcv(), bpf_lwt_input_reroute(), ip_expire(),
    ip_rcv_finish_core(), xfrm4_rcv_encap_finish() and
    xfrm4_rcv_encap(), which get the DSCP directly from IPv4 headers
    and can simply use the ip4h_dscp() helper.

While there, declare the IPv4 header pointers as const in
ipvlan_l3_rcv() and bpf_lwt_input_reroute().
Also, modify the declaration of ip_route_input_noref() in
include/net/route.h so that it matches the prototype of its
implementation in net/ipv4/route.c.

Signed-off-by: Guillaume Nault <gnault@redhat.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://patch.msgid.link/a8a747bed452519c4d0cc06af32c7e7795d7b627.1727807926.git.gnault@redhat.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-10-03 16:21:21 -07:00
Jakub Kicinski e7073830cc Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Cross-merge networking fixes after downstream PR.

No conflicts.

Adjacent changes:

drivers/net/ethernet/hisilicon/hns3/hns3pf/hclge_main.c
  35d92abfba ("net: hns3: fix kernel crash when devlink reload during initialization")
  2a1a1a7b5f ("net: hns3: add command queue trace for hns3")

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-05-09 10:01:01 -07:00
Paul DaveyandSteffen Klassert 58fbfecab9 xfrm: Preserve vlan tags for transport mode software GRO
The software GRO path for esp transport mode uses skb_mac_header_rebuild
prior to re-injecting the packet via the xfrm_napi_dev.  This only
copies skb->mac_len bytes of header which may not be sufficient if the
packet contains 802.1Q tags or other VLAN tags.  Worse copying only the
initial header will leave a packet marked as being VLAN tagged but
without the corresponding tag leading to mangling when it is later
untagged.

The VLAN tags are important when receiving the decrypted esp transport
mode packet after GRO processing to ensure it is received on the correct
interface.

Therefore record the full mac header length in xfrm*_transport_input for
later use in corresponding xfrm*_transport_finish to copy the entire mac
header when rebuilding the mac header for GRO.  The skb->data pointer is
left pointing skb->mac_header bytes after the start of the mac header as
is expected by the network stack and network and transport header
offsets reset to this location.

Fixes: 7785bba299 ("esp: Add a software GRO codepath")
Signed-off-by: Paul Davey <paul.davey@alliedtelesis.co.nz>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
2024-04-26 06:44:33 +02:00
Antony AntonyandSteffen Klassert aeb48a428d udpencap: Remove Obsolete UDP_ENCAP_ESPINUDP_NON_IKE Support
The UDP_ENCAP_ESPINUDP_NON_IKE mode, introduced into the Linux kernel
in 2004 [2], has remained inactive and obsolete for an extended period.

This mode was originally defined in an early version of an IETF draft
[1] from 2001. By the time it was integrated into the kernel in 2004 [2],
it had already been replaced by UDP_ENCAP_ESPINUDP [3] in later
versions of draft-ietf-ipsec-udp-encaps, particularly in version 06.

Over time, UDP_ENCAP_ESPINUDP_NON_IKE has lost its relevance, with no
known use cases.

With this commit, we remove support for UDP_ENCAP_ESPINUDP_NON_IKE,
simplifying the codebase and eliminating unnecessary complexity.
Kernel will return an error -ENOPROTOOPT if the userspace tries to set
this option.

References:
[1] https://datatracker.ietf.org/doc/html/draft-ietf-ipsec-udp-encaps-00.txt

[2] Commit that added UDP_ENCAP_ESPINUDP_NON_IKE to the Linux historic
    repository.

    Author: Andreas Gruenbacher <agruen@suse.de>
    Date: Fri Apr 9 01:47:47 2004 -0700

   [IPSEC]: Support draft-ietf-ipsec-udp-encaps-00/01, some ipec impls need it.

[3] Commit that added UDP_ENCAP_ESPINUDP to the Linux historic
    repository.

    Author: Derek Atkins <derek@ihtfp.com>
    Date: Wed Apr 2 13:21:02 2003 -0800

    [IPSEC]: Implement UDP Encapsulation framework.

Signed-off-by: Antony Antony <antony.antony@secunet.com>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
2024-04-18 11:38:23 +02:00
Eric DumazetandDavid S. Miller 80bfab79b8 net: adopt skb_network_offset() and similar helpers
This is a cleanup patch, making code a bit more concise.

1) Use skb_network_offset(skb) in place of
       (skb_network_header(skb) - skb->data)

2) Use -skb_network_offset(skb) in place of
       (skb->data - skb_network_header(skb))

3) Use skb_transport_offset(skb) in place of
       (skb_transport_header(skb) - skb->data)

4) Use skb_inner_transport_offset(skb) in place of
       (skb_inner_transport_header(skb) - skb->data)

Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Edward Cree <ecree.xilinx@gmail.com> # for sfc
Signed-off-by: David S. Miller <davem@davemloft.net>
2024-03-04 08:47:06 +00:00
Steffen Klassert 53a5b4f2ea xfrm Fix use after free in __xfrm6_udp_encap_rcv.
A recent patch changed xfrm6_udp_encap_rcv to not
free the skb itself anymore but fogot the case
where xfrm4_udp_encap_rcv is called subsequently.

Fix this by moving the call to xfrm4_udp_encap_rcv
from __xfrm6_udp_encap_rcv to xfrm6_udp_encap_rcv.

Fixes: 221ddb723d ("xfrm: Support GRO for IPv6 ESP in UDP encapsulation")
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
2023-10-23 07:10:39 +02:00
Steffen Klassert 172bf009c1 xfrm: Support GRO for IPv4 ESP in UDP encapsulation
This patch enables the GRO codepath for IPv4 ESP in UDP encapsulated
packets. Decapsulation happens at L2 and saves a full round through
the stack for each packet. This is also needed to support HW offload
for ESP in UDP encapsulation.

Enabling this would imporove performance for ESP in UDP datapath, i.e
IPsec with NAT in between.

By default GRP for ESP-in-UDP is disabled for UDP sockets.
To enable this feature for an ESP socket, the following two options
need to be set:
1. enable ESP-in-UDP: (this is already set by an IKE daemon).
   int type = UDP_ENCAP_ESPINUDP;
   setsockopt(fd, SOL_UDP, UDP_ENCAP, &type, sizeof(type));

2. To enable GRO for ESP in UDP socket:
   type = true;
   setsockopt(fd, SOL_UDP, UDP_GRO, &type, sizeof(type));

Enabling ESP-in-UDP has the side effect of preventing the Linux stack from
seeing ESP packets at the L3 (when ESP OFFLOAD is disabled), as packets are
immediately decapsulated from UDP and decrypted.
This change may affect nftable rules that match on ESP packets at L3.
Also tcpdump won't see the ESP packet.

Developers/admins are advised to review and adapt any nftable rules
accordingly before enabling this feature to prevent potential rule breakage.
Also tcpdump will not see from ESP packets from a ESP in UDP flow, when this
is enabled.

Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Co-developed-by: Antony Antony <antony.antony@secunet.com>
Signed-off-by: Antony Antony <antony.antony@secunet.com>
Reviewed-by: Eyal Birger <eyal.birger@gmail.com>
2023-10-06 07:30:40 +02:00
Eric DumazetandPaolo Abeni 70a36f5713 udp: annotate data-races around udp->encap_type
syzbot/KCSAN complained about UDP_ENCAP_L2TPINUDP setsockopt() racing.

Add READ_ONCE()/WRITE_ONCE() to document races on this lockless field.

syzbot report was:
BUG: KCSAN: data-race in udp_lib_setsockopt / udp_lib_setsockopt

read-write to 0xffff8881083603fa of 1 bytes by task 16557 on cpu 0:
udp_lib_setsockopt+0x682/0x6c0
udp_setsockopt+0x73/0xa0 net/ipv4/udp.c:2779
sock_common_setsockopt+0x61/0x70 net/core/sock.c:3697
__sys_setsockopt+0x1c9/0x230 net/socket.c:2263
__do_sys_setsockopt net/socket.c:2274 [inline]
__se_sys_setsockopt net/socket.c:2271 [inline]
__x64_sys_setsockopt+0x66/0x80 net/socket.c:2271
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x63/0xcd

read-write to 0xffff8881083603fa of 1 bytes by task 16554 on cpu 1:
udp_lib_setsockopt+0x682/0x6c0
udp_setsockopt+0x73/0xa0 net/ipv4/udp.c:2779
sock_common_setsockopt+0x61/0x70 net/core/sock.c:3697
__sys_setsockopt+0x1c9/0x230 net/socket.c:2263
__do_sys_setsockopt net/socket.c:2274 [inline]
__se_sys_setsockopt net/socket.c:2271 [inline]
__x64_sys_setsockopt+0x66/0x80 net/socket.c:2271
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x63/0xcd

value changed: 0x01 -> 0x05

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 16554 Comm: syz-executor.5 Not tainted 6.5.0-rc7-syzkaller-00004-gf7757129e3de #0

Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2023-09-14 16:16:36 +02:00
Maciej ŻenczykowskiandSteffen Klassert 1166a530a8 xfrm: fix inbound ipv4/udp/esp packets to UDPv6 dualstack sockets
Before Linux v5.8 an AF_INET6 SOCK_DGRAM (udp/udplite) socket
with SOL_UDP, UDP_ENCAP, UDP_ENCAP_ESPINUDP{,_NON_IKE} enabled
would just unconditionally use xfrm4_udp_encap_rcv(), afterwards
such a socket would use the newly added xfrm6_udp_encap_rcv()
which only handles IPv6 packets.

Cc: Sabrina Dubroca <sd@queasysnail.net>
Cc: Steffen Klassert <steffen.klassert@secunet.com>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: Benedict Wong <benedictwong@google.com>
Cc: Yan Yan <evitayan@google.com>
Fixes: 0146dca70b ("xfrm: add support for UDPv6 encapsulation of ESP")
Signed-off-by: Maciej Żenczykowski <maze@google.com>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Reviewed-by: Sabrina Dubroca <sd@queasysnail.net>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
2023-06-09 08:16:34 +02:00
Florian WestphalandSteffen Klassert a269fbfc4e xfrm: state: remove extract_input indirection from xfrm_state_afinfo
In order to keep CONFIG_IPV6=m working, xfrm6_extract_header needs to be
duplicated.  It will be removed again in a followup change when the
remaining caller is moved to net/xfrm as well.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
2020-05-06 09:40:08 +02:00
Sowmini VaradhanandSteffen Klassert bfc0698beb xfrm: reset transport header back to network header after all input transforms ahave been applied
A policy may have been set up with multiple transforms (e.g., ESP
and ipcomp). In this situation, the ingress IPsec processing
iterates in xfrm_input() and applies each transform in turn,
processing the nexthdr to find any additional xfrm that may apply.

This patch resets the transport header back to network header
only after the last transformation so that subsequent xfrms
can find the correct transport header.

Fixes: 7785bba299 ("esp: Add a software GRO codepath")
Suggested-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Sowmini Varadhan <sowmini.varadhan@oracle.com>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
2018-09-04 10:26:30 +02:00
Herbert XuandSteffen Klassert acf568ee85 xfrm: Reinject transport-mode packets through tasklet
This is an old bugbear of mine:

https://www.mail-archive.com/netdev@vger.kernel.org/msg03894.html

By crafting special packets, it is possible to cause recursion
in our kernel when processing transport-mode packets at levels
that are only limited by packet size.

The easiest one is with DNAT, but an even worse one is where
UDP encapsulation is used in which case you just have to insert
an UDP encapsulation header in between each level of recursion.

This patch avoids this problem by reinjecting tranport-mode packets
through a tasklet.

Fixes: b05e106698 ("[IPV4/6]: Netfilter IPsec input hooks")
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
2017-12-19 08:23:21 +01:00
Greg Kroah-Hartman b24413180f License cleanup: add SPDX GPL-2.0 license identifier to files with no license
Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.

By default all files without license information are under the default
license of the kernel, which is GPL version 2.

Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier.  The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.

This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.

How this work was done:

Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
 - file had no licensing information it it.
 - file was a */uapi/* one with no licensing information in it,
 - file was a */uapi/* one with existing licensing information,

Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.

The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne.  Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.

The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed.  Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.

Criteria used to select files for SPDX license identifier tagging was:
 - Files considered eligible had to be source code files.
 - Make and config files were included as candidates if they contained >5
   lines of source
 - File already had some variant of a license header in it (even if <5
   lines).

All documentation files were explicitly excluded.

The following heuristics were used to determine which SPDX license
identifiers to apply.

 - when both scanners couldn't find any license traces, file was
   considered to have no license information in it, and the top level
   COPYING file license applied.

   For non */uapi/* files that summary was:

   SPDX license identifier                            # files
   ---------------------------------------------------|-------
   GPL-2.0                                              11139

   and resulted in the first patch in this series.

   If that file was a */uapi/* path one, it was "GPL-2.0 WITH
   Linux-syscall-note" otherwise it was "GPL-2.0".  Results of that was:

   SPDX license identifier                            # files
   ---------------------------------------------------|-------
   GPL-2.0 WITH Linux-syscall-note                        930

   and resulted in the second patch in this series.

 - if a file had some form of licensing information in it, and was one
   of the */uapi/* ones, it was denoted with the Linux-syscall-note if
   any GPL family license was found in the file or had no licensing in
   it (per prior point).  Results summary:

   SPDX license identifier                            # files
   ---------------------------------------------------|------
   GPL-2.0 WITH Linux-syscall-note                       270
   GPL-2.0+ WITH Linux-syscall-note                      169
   ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause)    21
   ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause)    17
   LGPL-2.1+ WITH Linux-syscall-note                      15
   GPL-1.0+ WITH Linux-syscall-note                       14
   ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause)    5
   LGPL-2.0+ WITH Linux-syscall-note                       4
   LGPL-2.1 WITH Linux-syscall-note                        3
   ((GPL-2.0 WITH Linux-syscall-note) OR MIT)              3
   ((GPL-2.0 WITH Linux-syscall-note) AND MIT)             1

   and that resulted in the third patch in this series.

 - when the two scanners agreed on the detected license(s), that became
   the concluded license(s).

 - when there was disagreement between the two scanners (one detected a
   license but the other didn't, or they both detected different
   licenses) a manual inspection of the file occurred.

 - In most cases a manual inspection of the information in the file
   resulted in a clear resolution of the license that should apply (and
   which scanner probably needed to revisit its heuristics).

 - When it was not immediately clear, the license identifier was
   confirmed with lawyers working with the Linux Foundation.

 - If there was any question as to the appropriate license identifier,
   the file was flagged for further research and to be revisited later
   in time.

In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.

Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights.  The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.

Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.

In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.

Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
 - a full scancode scan run, collecting the matched texts, detected
   license ids and scores
 - reviewing anything where there was a license detected (about 500+
   files) to ensure that the applied SPDX license was correct
 - reviewing anything where there was no detection but the patch license
   was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
   SPDX license was correct

This produced a worksheet with 20 files needing minor correction.  This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.

These .csv files were then reviewed by Greg.  Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected.  This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.)  Finally Greg ran the script using the .csv files to
generate the patches.

Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-02 11:10:55 +01:00
Steffen Klassert 7785bba299 esp: Add a software GRO codepath
This patch adds GRO ifrastructure and callbacks for ESP on
ipv4 and ipv6.

In case the GRO layer detects an ESP packet, the
esp{4,6}_gro_receive() function does a xfrm state lookup
and calls the xfrm input layer if it finds a matching state.
The packet will be decapsulated and reinjected it into layer 2.

Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
2017-02-15 11:04:11 +01:00
Eric W. BiedermanandDavid S. Miller 0c4b51f005 netfilter: Pass net into okfn
This is immediately motivated by the bridge code that chains functions that
call into netfilter.  Without passing net into the okfns the bridge code would
need to guess about the best expression for the network namespace to process
packets in.

As net is frequently one of the first things computed in continuation functions
after netfilter has done it's job passing in the desired network namespace is in
many cases a code simplification.

To support this change the function dst_output_okfn is introduced to
simplify passing dst_output as an okfn.  For the moment dst_output_okfn
just silently drops the struct net.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-09-17 17:18:37 -07:00
Eric W. BiedermanandDavid S. Miller 29a26a5680 netfilter: Pass struct net into the netfilter hooks
Pass a network namespace parameter into the netfilter hooks.  At the
call site of the netfilter hooks the path a packet is taking through
the network stack is well known which allows the network namespace to
be easily and reliabily.

This allows the replacement of magic code like
"dev_net(state->in?:state->out)" that appears at the start of most
netfilter hooks with "state->net".

In almost all cases the network namespace passed in is derived
from the first network device passed in, guaranteeing those
paths will not see any changes in practice.

The exceptions are:
xfrm/xfrm_output.c:xfrm_output_resume()         xs_net(skb_dst(skb)->xfrm)
ipvs/ip_vs_xmit.c:ip_vs_nat_send_or_cont()      ip_vs_conn_net(cp)
ipvs/ip_vs_xmit.c:ip_vs_send_or_cont()          ip_vs_conn_net(cp)
ipv4/raw.c:raw_send_hdrinc()                    sock_net(sk)
ipv6/ip6_output.c:ip6_xmit()			sock_net(sk)
ipv6/ndisc.c:ndisc_send_skb()                   dev_net(skb->dev) not dev_net(dst->dev)
ipv6/raw.c:raw6_send_hdrinc()                   sock_net(sk)
br_netfilter_hooks.c:br_nf_pre_routing_finish() dev_net(skb->dev) before skb->dev is set to nf_bridge->physindev

In all cases these exceptions seem to be a better expression for the
network namespace the packet is being processed in then the historic
"dev_net(in?in:out)".  I am documenting them in case something odd
pops up and someone starts trying to track down what happened.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-09-17 17:18:37 -07:00
David Miller 7026b1ddb6 netfilter: Pass socket pointer down through okfn().
On the output paths in particular, we have to sometimes deal with two
socket contexts.  First, and usually skb->sk, is the local socket that
generated the frame.

And second, is potentially the socket used to control a tunneling
socket, such as one the encapsulates using UDP.

We do not want to disassociate skb->sk when encapsulating in order
to fix this, because that would break socket memory accounting.

The most extreme case where this can cause huge problems is an
AF_PACKET socket transmitting over a vxlan device.  We hit code
paths doing checks that assume they are dealing with an ipv4
socket, but are actually operating upon the AF_PACKET one.

Signed-off-by: David S. Miller <davem@davemloft.net>
2015-04-07 15:25:55 -04:00
Ian MorrisandDavid S. Miller 51456b2914 ipv4: coding style: comparison for equality with NULL
The ipv4 code uses a mixture of coding styles. In some instances check
for NULL pointer is done as x == NULL and sometimes as !x. !x is
preferred according to checkpatch and this patch makes the code
consistent by adopting the latter form.

No changes detected by objdiff.

Signed-off-by: Ian Morris <ipm@chirality.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-04-03 12:11:15 -04:00
Steffen Klassert 3328715e6c xfrm4: Add IPsec protocol multiplexer
This patch add an IPsec protocol multiplexer. With this
it is possible to add alternative protocol handlers as
needed for IPsec virtual tunnel interfaces.

Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
2014-02-25 07:04:16 +01:00
Pravin B ShelarandDavid S. Miller 14bbd6a565 net: Add skb_unclone() helper function.
This function will be used in next GRE_GSO patch. This patch does
not change any functionality.

Signed-off-by: Pravin B Shelar <pshelar@nicira.com>
Acked-by: Eric Dumazet <edumazet@google.com>
2013-02-15 15:10:37 -05:00
David S. Miller c6cffba4ff ipv4: Fix input route performance regression.
With the routing cache removal we lost the "noref" code paths on
input, and this can kill some routing workloads.

Reinstate the noref path when we hit a cached route in the FIB
nexthops.

With help from Eric Dumazet.

Reported-by: Alexander Duyck <alexander.duyck@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-07-26 15:50:39 -07:00
David Miller 38a424e465 ipv4: Kill ip_route_input_noref().
The "noref" argument to ip_route_input_common() is now always ignored
because we do not cache routes, and in that case we must always grab
a reference to the resulting 'dst'.

Signed-off-by: David S. Miller <davem@davemloft.net>
2012-07-20 13:30:59 -07:00