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436 commits

Author SHA1 Message Date
Willem de Bruijn 59c820b231 ipv6: elide flowlabel check if no exclusive leases exist
Processes can request ipv6 flowlabels with cmsg IPV6_FLOWINFO.
If not set, by default an autogenerated flowlabel is selected.

Explicit flowlabels require a control operation per label plus a
datapath check on every connection (every datagram if unconnected).
This is particularly expensive on unconnected sockets multiplexing
many flows, such as QUIC.

In the common case, where no lease is exclusive, the check can be
safely elided, as both lease request and check trivially succeed.
Indeed, autoflowlabel does the same even with exclusive leases.

Elide the check if no process has requested an exclusive lease.

fl6_sock_lookup previously returns either a reference to a lease or
NULL to denote failure. Modify to return a real error and update
all callers. On return NULL, they can use the label and will elide
the atomic_dec in fl6_sock_release.

This is an optimization. Robust applications still have to revert to
requesting leases if the fast path fails due to an exclusive lease.

Changes RFC->v1:
  - use static_key_false_deferred to rate limit jump label operations
    - call static_key_deferred_flush to stop timers on exit
  - move decrement out of RCU context
  - defer optimization also if opt data is associated with a lease
  - updated all fp6_sock_lookup callers, not just udp

Signed-off-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-07-08 19:38:03 -07:00
Li RongQing e4aa33ad59 net: remove unused parameter from skb_checksum_try_convert
the check parameter is never used

Signed-off-by: Li RongQing <lirongqing@baidu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-07-05 15:30:36 -07:00
David S. Miller 13091aa305 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Honestly all the conflicts were simple overlapping changes,
nothing really interesting to report.

Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-17 20:20:36 -07:00
Tim Beale f48d2ccee1 udp: Remove unused variable/function (exact_dif)
This was originally passed through to the VRF logic in compute_score().
But that logic has now been replaced by udp_sk_bound_dev_eq() and so
this code is no longer used or needed.

Signed-off-by: Tim Beale <timbeale@catalyst.net.nz>
Reviewed-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-14 19:52:07 -07:00
Tim Beale 735453730a udp: Remove unused parameter (exact_dif)
Originally this was used by the VRF logic in compute_score(), but that
was later replaced by udp_sk_bound_dev_eq() and the parameter became
unused.

Note this change adds an 'unused variable' compiler warning that will be
removed in the next patch (I've split the removal in two to make review
slightly easier).

Signed-off-by: Tim Beale <timbeale@catalyst.net.nz>
Reviewed-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-14 19:52:07 -07:00
David S. Miller 38e406f600 Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf
Daniel Borkmann says:

====================
pull-request: bpf 2019-06-07

The following pull-request contains BPF updates for your *net* tree.

The main changes are:

1) Fix several bugs in riscv64 JIT code emission which forgot to clear high
   32-bits for alu32 ops, from Björn and Luke with selftests covering all
   relevant BPF alu ops from Björn and Jiong.

2) Two fixes for UDP BPF reuseport that avoid calling the program in case of
   __udp6_lib_err and UDP GRO which broke reuseport_select_sock() assumption
   that skb->data is pointing to transport header, from Martin.

3) Two fixes for BPF sockmap: a use-after-free from sleep in psock's backlog
   workqueue, and a missing restore of sk_write_space when psock gets dropped,
   from Jakub and John.

4) Fix unconnected UDP sendmsg hook API which is insufficient as-is since it
   breaks standard applications like DNS if reverse NAT is not performed upon
   receive, from Daniel.

5) Fix an out-of-bounds read in __bpf_skc_lookup which in case of AF_INET6
   fails to verify that the length of the tuple is long enough, from Lorenz.

6) Fix libbpf's libbpf__probe_raw_btf to return an fd instead of 0/1 (for
   {un,}successful probe) as that is expected to be propagated as an fd to
   load_sk_storage_btf() and thus closing the wrong descriptor otherwise,
   from Michal.

7) Fix bpftool's JSON output for the case when a lookup fails, from Krzesimir.

8) Minor misc fixes in docs, samples and selftests, from various others.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-07 14:46:47 -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
Daniel Borkmann 983695fa67 bpf: fix unconnected udp hooks
Intention of cgroup bind/connect/sendmsg BPF hooks is to act transparently
to applications as also stated in original motivation in 7828f20e37 ("Merge
branch 'bpf-cgroup-bind-connect'"). When recently integrating the latter
two hooks into Cilium to enable host based load-balancing with Kubernetes,
I ran into the issue that pods couldn't start up as DNS got broken. Kubernetes
typically sets up DNS as a service and is thus subject to load-balancing.

Upon further debugging, it turns out that the cgroupv2 sendmsg BPF hooks API
is currently insufficient and thus not usable as-is for standard applications
shipped with most distros. To break down the issue we ran into with a simple
example:

  # cat /etc/resolv.conf
  nameserver 147.75.207.207
  nameserver 147.75.207.208

For the purpose of a simple test, we set up above IPs as service IPs and
transparently redirect traffic to a different DNS backend server for that
node:

  # cilium service list
  ID   Frontend            Backend
  1    147.75.207.207:53   1 => 8.8.8.8:53
  2    147.75.207.208:53   1 => 8.8.8.8:53

The attached BPF program is basically selecting one of the backends if the
service IP/port matches on the cgroup hook. DNS breaks here, because the
hooks are not transparent enough to applications which have built-in msg_name
address checks:

  # nslookup 1.1.1.1
  ;; reply from unexpected source: 8.8.8.8#53, expected 147.75.207.207#53
  ;; reply from unexpected source: 8.8.8.8#53, expected 147.75.207.208#53
  ;; reply from unexpected source: 8.8.8.8#53, expected 147.75.207.207#53
  [...]
  ;; connection timed out; no servers could be reached

  # dig 1.1.1.1
  ;; reply from unexpected source: 8.8.8.8#53, expected 147.75.207.207#53
  ;; reply from unexpected source: 8.8.8.8#53, expected 147.75.207.208#53
  ;; reply from unexpected source: 8.8.8.8#53, expected 147.75.207.207#53
  [...]

  ; <<>> DiG 9.11.3-1ubuntu1.7-Ubuntu <<>> 1.1.1.1
  ;; global options: +cmd
  ;; connection timed out; no servers could be reached

For comparison, if none of the service IPs is used, and we tell nslookup
to use 8.8.8.8 directly it works just fine, of course:

  # nslookup 1.1.1.1 8.8.8.8
  1.1.1.1.in-addr.arpa	name = one.one.one.one.

In order to fix this and thus act more transparent to the application,
this needs reverse translation on recvmsg() side. A minimal fix for this
API is to add similar recvmsg() hooks behind the BPF cgroups static key
such that the program can track state and replace the current sockaddr_in{,6}
with the original service IP. From BPF side, this basically tracks the
service tuple plus socket cookie in an LRU map where the reverse NAT can
then be retrieved via map value as one example. Side-note: the BPF cgroups
static key should be converted to a per-hook static key in future.

Same example after this fix:

  # cilium service list
  ID   Frontend            Backend
  1    147.75.207.207:53   1 => 8.8.8.8:53
  2    147.75.207.208:53   1 => 8.8.8.8:53

Lookups work fine now:

  # nslookup 1.1.1.1
  1.1.1.1.in-addr.arpa    name = one.one.one.one.

  Authoritative answers can be found from:

  # dig 1.1.1.1

  ; <<>> DiG 9.11.3-1ubuntu1.7-Ubuntu <<>> 1.1.1.1
  ;; global options: +cmd
  ;; Got answer:
  ;; ->>HEADER<<- opcode: QUERY, status: NXDOMAIN, id: 51550
  ;; flags: qr rd ra ad; QUERY: 1, ANSWER: 0, AUTHORITY: 1, ADDITIONAL: 1

  ;; OPT PSEUDOSECTION:
  ; EDNS: version: 0, flags:; udp: 512
  ;; QUESTION SECTION:
  ;1.1.1.1.                       IN      A

  ;; AUTHORITY SECTION:
  .                       23426   IN      SOA     a.root-servers.net. nstld.verisign-grs.com. 2019052001 1800 900 604800 86400

  ;; Query time: 17 msec
  ;; SERVER: 147.75.207.207#53(147.75.207.207)
  ;; WHEN: Tue May 21 12:59:38 UTC 2019
  ;; MSG SIZE  rcvd: 111

And from an actual packet level it shows that we're using the back end
server when talking via 147.75.207.20{7,8} front end:

  # tcpdump -i any udp
  [...]
  12:59:52.698732 IP foo.42011 > google-public-dns-a.google.com.domain: 18803+ PTR? 1.1.1.1.in-addr.arpa. (38)
  12:59:52.698735 IP foo.42011 > google-public-dns-a.google.com.domain: 18803+ PTR? 1.1.1.1.in-addr.arpa. (38)
  12:59:52.701208 IP google-public-dns-a.google.com.domain > foo.42011: 18803 1/0/0 PTR one.one.one.one. (67)
  12:59:52.701208 IP google-public-dns-a.google.com.domain > foo.42011: 18803 1/0/0 PTR one.one.one.one. (67)
  [...]

In order to be flexible and to have same semantics as in sendmsg BPF
programs, we only allow return codes in [1,1] range. In the sendmsg case
the program is called if msg->msg_name is present which can be the case
in both, connected and unconnected UDP.

The former only relies on the sockaddr_in{,6} passed via connect(2) if
passed msg->msg_name was NULL. Therefore, on recvmsg side, we act in similar
way to call into the BPF program whenever a non-NULL msg->msg_name was
passed independent of sk->sk_state being TCP_ESTABLISHED or not. Note
that for TCP case, the msg->msg_name is ignored in the regular recvmsg
path and therefore not relevant.

For the case of ip{,v6}_recv_error() paths, picked up via MSG_ERRQUEUE,
the hook is not called. This is intentional as it aligns with the same
semantics as in case of TCP cgroup BPF hooks right now. This might be
better addressed in future through a different bpf_attach_type such
that this case can be distinguished from the regular recvmsg paths,
for example.

Fixes: 1cedee13d2 ("bpf: Hooks for sys_sendmsg")
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Andrey Ignatov <rdna@fb.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Acked-by: Martynas Pumputis <m@lambda.lt>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2019-06-06 16:53:12 -07:00
Enrico Weigelt 26f8113cc7 net: ipv6: drop unneeded likely() call around IS_ERR()
IS_ERR() already calls unlikely(), so this extra unlikely() call
around IS_ERR() is not needed.

Signed-off-by: Enrico Weigelt <info@metux.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-05 16:57:23 -07:00
Martin KaFai Lau 257a525fe2 bpf: udp: Avoid calling reuseport's bpf_prog from udp_gro
When the commit a6024562ff ("udp: Add GRO functions to UDP socket")
added udp[46]_lib_lookup_skb to the udp_gro code path, it broke
the reuseport_select_sock() assumption that skb->data is pointing
to the transport header.

This patch follows an earlier __udp6_lib_err() fix by
passing a NULL skb to avoid calling the reuseport's bpf_prog.

Fixes: a6024562ff ("udp: Add GRO functions to UDP socket")
Cc: Tom Herbert <tom@herbertland.com>
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Acked-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2019-06-03 13:38:48 -07:00
Martin KaFai Lau 4ac30c4b36 bpf: udp: ipv6: Avoid running reuseport's bpf_prog from __udp6_lib_err
__udp6_lib_err() may be called when handling icmpv6 message. For example,
the icmpv6 toobig(type=2).  __udp6_lib_lookup() is then called
which may call reuseport_select_sock().  reuseport_select_sock() will
call into a bpf_prog (if there is one).

reuseport_select_sock() is expecting the skb->data pointing to the
transport header (udphdr in this case).  For example, run_bpf_filter()
is pulling the transport header.

However, in the __udp6_lib_err() path, the skb->data is pointing to the
ipv6hdr instead of the udphdr.

One option is to pull and push the ipv6hdr in __udp6_lib_err().
Instead of doing this, this patch follows how the original
commit 538950a1b7 ("soreuseport: setsockopt SO_ATTACH_REUSEPORT_[CE]BPF")
was done in IPv4, which has passed a NULL skb pointer to
reuseport_select_sock().

Fixes: 538950a1b7 ("soreuseport: setsockopt SO_ATTACH_REUSEPORT_[CE]BPF")
Cc: Craig Gallek <kraig@google.com>
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Acked-by: Song Liu <songliubraving@fb.com>
Acked-by: Craig Gallek <kraig@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2019-06-03 13:38:48 -07:00
Thomas Gleixner 2874c5fd28 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152
Based on 1 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

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 3029 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-30 11:26:32 -07:00
Paolo Abeni 97ff7ffb11 net: use indirect calls helpers at early demux stage
So that we avoid another indirect call per RX packet, if
early demux is enabled.

Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-05-05 10:38:04 -07:00
Paolo Abeni 0e219ae48c net: use indirect calls helpers for L3 handler hooks
So that we avoid another indirect call per RX packet in the common
case.

Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-05-05 10:38:04 -07:00
David S. Miller 6b0a7f84ea Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Conflict resolution of af_smc.c from Stephen Rothwell.

Signed-off-by: David S. Miller <davem@davemloft.net>
2019-04-17 11:26:25 -07:00
Tetsuo Handa bddc028a4f udpv6: Check address length before reading address family
KMSAN will complain if valid address length passed to udpv6_pre_connect()
is shorter than sizeof("struct sockaddr"->sa_family) bytes.

(This patch is bogus if it is guaranteed that udpv6_pre_connect() is
always called after checking "struct sockaddr"->sa_family. In that case,
we want a comment why we don't need to check valid address length here.)

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Acked-by: Song Liu <songliubraving@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-04-12 10:25:03 -07:00
Paolo Abeni fd69c399c7 datagram: remove rendundant 'peeked' argument
After commit a297569fe0 ("net/udp: do not touch skb->peeked unless
really needed") the 'peeked' argument of __skb_try_recv_datagram()
and friends is always equal to !!'flags & MSG_PEEK'.

Since such argument is really a boolean info, and the callers have
already 'flags & MSG_PEEK' handy, we can remove it and clean-up the
code a bit.

Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Acked-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-04-08 09:51:54 -07:00
Paolo Abeni 424a7cd078 udpv6: fix possible user after free in error handler
Before derefencing the encap pointer, commit e7cc082455 ("udp: Support
for error handlers of tunnels with arbitrary destination port") checks
for a NULL value, but the two fetch operation can race with removal.
Fix the above using a single access.
Also fix a couple of type annotations, to make sparse happy.

Fixes: e7cc082455 ("udp: Support for error handlers of tunnels with arbitrary destination port")
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Acked-by: Stefano Brivio <sbrivio@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-02-22 16:05:11 -08:00
Paolo Abeni 543fc3fb41 udpv6: add the required annotation to mib type
In commit 029a374348 ("udp6: cleanup stats accounting in recvmsg()")
I forgot to add the percpu annotation for the mib pointer. Add it, and
make sparse happy.

Fixes: 029a374348 ("udp6: cleanup stats accounting in recvmsg()")
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-02-22 16:05:11 -08:00
Alexey Kodanev f7c46156f4 udp6: add missing rehash callback to udplite
After commit 23b0269e58 ("net: udp6: prefer listeners bound to an
address"), UDP-Lite only works when specifying a local address for
the sockets.

This is related to the problem addressed in the commit 719f835853
("udp: add rehash on connect()"). Moreover, __udp6_lib_lookup() now
looks for a socket immediately in the secondary hash table.

And this issue was found with LTP/network tests as well.

Fixes: 23b0269e58 ("net: udp6: prefer listeners bound to an address")
Signed-off-by: Alexey Kodanev <alexey.kodanev@oracle.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-01-17 15:01:08 -08:00
Willem de Bruijn 0f149c9fec udp: with udp_segment release on error path
Failure __ip_append_data triggers udp_flush_pending_frames, but these
tests happen later. The skb must be freed directly.

Fixes: bec1f6f697 ("udp: generate gso with UDP_SEGMENT")
Reported-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-01-16 15:48:11 -08:00
Andrey Ignatov e8e3698408 bpf: Fix [::] -> [::1] rewrite in sys_sendmsg
sys_sendmsg has supported unspecified destination IPv6 (wildcard) for
unconnected UDP sockets since 876c7f41. When [::] is passed by user as
destination, sys_sendmsg rewrites it with [::1] to be consistent with
BSD (see "BSD'ism" comment in the code).

This didn't work when cgroup-bpf was enabled though since the rewrite
[::] -> [::1] happened before passing control to cgroup-bpf block where
fl6.daddr was updated with passed by user sockaddr_in6.sin6_addr (that
might or might not be changed by BPF program). That way if user passed
[::] as dst IPv6 it was first rewritten with [::1] by original code from
876c7f41, but then rewritten back with [::] by cgroup-bpf block.

It happened even when BPF_CGROUP_UDP6_SENDMSG program was not present
(CONFIG_CGROUP_BPF=y was enough).

The fix is to apply BSD'ism after cgroup-bpf block so that [::] is
replaced with [::1] no matter where it came from: passed by user to
sys_sendmsg or set by BPF_CGROUP_UDP6_SENDMSG program.

Fixes: 1cedee13d2 ("bpf: Hooks for sys_sendmsg")
Reported-by: Nitin Rawat <nitin.rawat@intel.com>
Signed-off-by: Andrey Ignatov <rdna@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2019-01-04 20:23:33 -08:00
Peter Oskolkov 23b0269e58 net: udp6: prefer listeners bound to an address
A relatively common use case is to have several IPs configured
on a host, and have different listeners for each of them. We would
like to add a "catch all" listener on addr_any, to match incoming
connections not served by any of the listeners bound to a specific
address.

However, port-only lookups can match addr_any sockets when sockets
listening on specific addresses are present if so_reuseport flag
is set. This patch eliminates lookups into port-only hashtable,
as lookups by (addr,port) tuple are easily available.

In addition, compute_score() is tweaked to _not_ match
addr_any sockets to specific addresses, as hash collisions
could result in the unwanted behavior described above.

Tested: the patch compiles; full test in the last patch in this
patchset. Existing reuseport_* selftests also pass.

Suggested-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Peter Oskolkov <posk@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-12-14 15:55:20 -08:00
Paolo Abeni 9c48060141 udp: fix jump label misuse
The commit 60fb9567bf ("udp: implement complete book-keeping for
encap_needed") introduced a severe misuse of jump label APIs, which
syzbot, as reported by Eric, was able to exploit.

When multiple sockets/process can concurrently request (and than
disable) the udp encap, we need to track the activation counter with
*_inc()/*_dec() jump label variants, or we can experience bad things
at disable time.

Fixes: 60fb9567bf ("udp: implement complete book-keeping for encap_needed")
Reported-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-11-16 23:01:56 -08:00
Paolo Abeni 029a374348 udp6: cleanup stats accounting in recvmsg()
In the udp6 code path, we needed multiple tests to select the correct
mib to be updated. Since we touch at least a counter at each iteration,
it's convenient to use the recently introduced __UDPX_MIB() helper once
and remove some code duplication.

Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-11-09 20:07:05 -08:00
Stefano Brivio e7cc082455 udp: Support for error handlers of tunnels with arbitrary destination port
ICMP error handling is currently not possible for UDP tunnels not
employing a receiving socket with local destination port matching the
remote one, because we have no way to look them up.

Add an err_handler tunnel encapsulation operation that can be exported by
tunnels in order to pass the error to the protocol implementing the
encapsulation. We can't easily use a lookup function as we did for VXLAN
and GENEVE, as protocol error handlers, which would be in turn called by
implementations of this new operation, handle the errors themselves,
together with the tunnel lookup.

Without a socket, we can't be sure which encapsulation error handler is
the appropriate one: encapsulation handlers (the ones for FoU and GUE
introduced in the next patch, e.g.) will need to check the new error codes
returned by protocol handlers to figure out if errors match the given
encapsulation, and, in turn, report this error back, so that we can try
all of them in __udp{4,6}_lib_err_encap_no_sk() until we have a match.

v2:
- Name all arguments in err_handler prototypes (David Miller)

Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
Reviewed-by: Sabrina Dubroca <sd@queasysnail.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-11-08 17:13:08 -08:00
Stefano Brivio 32bbd8793f net: Convert protocol error handlers from void to int
We'll need this to handle ICMP errors for tunnels without a sending socket
(i.e. FoU and GUE). There, we might have to look up different types of IP
tunnels, registered as network protocols, before we get a match, so we
want this for the error handlers of IPPROTO_IPIP and IPPROTO_IPV6 in both
inet_protos and inet6_protos. These error codes will be used in the next
patch.

For consistency, return sensible error codes in protocol error handlers
whenever handlers can't handle errors because, even if valid, they don't
match a protocol or any of its states.

This has no effect on existing error handling paths.

Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
Reviewed-by: Sabrina Dubroca <sd@queasysnail.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-11-08 17:13:08 -08:00
Stefano Brivio a36e185e8c udp: Handle ICMP errors for tunnels with same destination port on both endpoints
For both IPv4 and IPv6, if we can't match errors to a socket, try
tunnels before ignoring them. Look up a socket with the original source
and destination ports as found in the UDP packet inside the ICMP payload,
this will work for tunnels that force the same destination port for both
endpoints, i.e. VXLAN and GENEVE.

Actually, lwtunnels could break this assumption if they are configured by
an external control plane to have different destination ports on the
endpoints: in this case, we won't be able to trace ICMP messages back to
them.

For IPv6 redirect messages, call ip6_redirect() directly with the output
interface argument set to the interface we received the packet from (as
it's the very interface we should build the exception on), otherwise the
new nexthop will be rejected. There's no such need for IPv4.

Tunnels can now export an encap_err_lookup() operation that indicates a
match. Pass the packet to the lookup function, and if the tunnel driver
reports a matching association, continue with regular ICMP error handling.

v2:
- Added newline between network and transport header sets in
  __udp{4,6}_lib_err_encap() (David Miller)
- Removed redundant skb_reset_network_header(skb); in
  __udp4_lib_err_encap()
- Removed redundant reassignment of iph in __udp4_lib_err_encap()
  (Sabrina Dubroca)
- Edited comment to __udp{4,6}_lib_err_encap() to reflect the fact this
  won't work with lwtunnels configured to use asymmetric ports. By the way,
  it's VXLAN, not VxLAN (Jiri Benc)

Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
Reviewed-by: Sabrina Dubroca <sd@queasysnail.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-11-08 17:13:08 -08:00
Paolo Abeni cf329aa42b udp: cope with UDP GRO packet misdirection
In some scenarios, the GRO engine can assemble an UDP GRO packet
that ultimately lands on a non GRO-enabled socket.
This patch tries to address the issue explicitly checking for the UDP
socket features before enqueuing the packet, and eventually segmenting
the unexpected GRO packet, as needed.

We must also cope with re-insertion requests: after segmentation the
UDP code calls the helper introduced by the previous patches, as needed.

Segmentation is performed by a common helper, which takes care of
updating socket and protocol stats is case of failure.

rfc v3 -> v1
 - fix compile issues with rxrpc
 - when gso_segment returns NULL, treat is as an error
 - added 'ipv4' argument to udp_rcv_segment()

rfc v2 -> rfc v3
 - moved udp_rcv_segment() into net/udp.h, account errors to socket
   and ns, always return NULL or segs list

Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-11-07 16:23:05 -08:00
Paolo Abeni bcd1665e35 udp: add support for UDP_GRO cmsg
When UDP GRO is enabled, the UDP_GRO cmsg will carry the ingress
datagram size. User-space can use such info to compute the original
packets layout.

Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-11-07 16:23:04 -08:00
Paolo Abeni 60fb9567bf udp: implement complete book-keeping for encap_needed
The *encap_needed static keys are enabled by UDP tunnels
and several UDP encapsulations type, but they are never
turned off. This can cause unneeded overall performance
degradation for systems where such features are used
transiently.

This patch introduces complete book-keeping for such keys,
decreasing the usage at socket destruction time, if needed,
and avoiding that the same socket could increase the key
usage multiple times.

rfc v3 -> v1:
 - add socket lock around udp_tunnel_encap_enable()

rfc v2 -> rfc v3:
 - use udp_tunnel_encap_enable() in setsockopt()

Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-11-07 16:23:04 -08:00
Dewi Morgan 7bd2db404e ipv6: do not drop vrf udp multicast packets
For bound udp sockets in a vrf, also check the sdif to get the index
for ingress devices enslaved to an l3mdev.

Signed-off-by: Dewi Morgan <morgand@vyatta.att-mail.com>
Signed-off-by: Mike Manning <mmanning@vyatta.att-mail.com>
Reviewed-by: David Ahern <dsahern@gmail.com>
Tested-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-11-07 16:12:39 -08:00
Mike Manning 6da5b0f027 net: ensure unbound datagram socket to be chosen when not in a VRF
Ensure an unbound datagram skt is chosen when not in a VRF. The check
for a device match in compute_score() for UDP must be performed when
there is no device match. For this, a failure is returned when there is
no device match. This ensures that bound sockets are never selected,
even if there is no unbound socket.

Allow IPv6 packets to be sent over a datagram skt bound to a VRF. These
packets are currently blocked, as flowi6_oif was set to that of the
master vrf device, and the ipi6_ifindex is that of the slave device.
Allow these packets to be sent by checking the device with ipi6_ifindex
has the same L3 scope as that of the bound device of the skt, which is
the master vrf device. Note that this check always succeeds if the skt
is unbound.

Even though the right datagram skt is now selected by compute_score(),
a different skt is being returned that is bound to the wrong vrf. The
difference between these and stream sockets is the handling of the skt
option for SO_REUSEPORT. While the handling when adding a skt for reuse
correctly checks that the bound device of the skt is a match, the skts
in the hashslot are already incorrect. So for the same hash, a skt for
the wrong vrf may be selected for the required port. The root cause is
that the skt is immediately placed into a slot when it is created,
but when the skt is then bound using SO_BINDTODEVICE, it remains in the
same slot. The solution is to move the skt to the correct slot by
forcing a rehash.

Signed-off-by: Mike Manning <mmanning@vyatta.att-mail.com>
Reviewed-by: David Ahern <dsahern@gmail.com>
Tested-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-11-07 16:12:38 -08:00
Mike Manning f64bf6b8ae net: allow traceroute with a specified interface in a vrf
Traceroute executed in a vrf succeeds if no device is given or if the
vrf is given as the device, but fails if the interface is given as the
device. This is for default UDP probes, it succeeds for TCP SYN or ICMP
ECHO probes. As the skb bound dev is the interface and the sk dev is
the vrf, sk lookup fails for ICMP_DEST_UNREACH and ICMP_TIME_EXCEEDED
messages. The solution is for the secondary dev to be passed so that
the interface is available for the device match to succeed, in the same
way as is already done for non-error cases.

Signed-off-by: Mike Manning <mmanning@vyatta.att-mail.com>
Reviewed-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-26 16:03:08 -07:00
David S. Miller 2e2d6f0342 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
net/sched/cls_api.c has overlapping changes to a call to
nlmsg_parse(), one (from 'net') added rtm_tca_policy instead of NULL
to the 5th argument, and another (from 'net-next') added cb->extack
instead of NULL to the 6th argument.

net/ipv4/ipmr_base.c is a case of a bug fix in 'net' being done to
code which moved (to mr_table_dump)) in 'net-next'.  Thanks to David
Ahern for the heads up.

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-19 11:03:06 -07:00
Paolo Abeni 84dad55951 udp6: fix encap return code for resubmitting
The commit eb63f2964d ("udp6: add missing checks on edumux packet
processing") used the same return code convention of the ipv4 counterpart,
but ipv6 uses the opposite one: positive values means resubmit.

This change addresses the issue, using positive return value for
resubmitting. Also update the related comment, which was broken, too.

Fixes: eb63f2964d ("udp6: add missing checks on edumux packet processing")
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-17 22:26:53 -07:00
Willem de Bruijn f2e9de210d udp: gro behind static key
Avoid the socket lookup cost in udp_gro_receive if no socket has a
udp tunnel callback configured.

udp_sk(sk)->gro_receive requires a registration with
setup_udp_tunnel_sock, which enables the static key.

Signed-off-by: Willem de Bruijn <willemb@google.com>
Acked-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-05 11:52:38 -07:00
Paolo Abeni eb63f2964d udp6: add missing checks on edumux packet processing
Currently the UDPv6 early demux rx code path lacks some mandatory
checks, already implemented into the normal RX code path - namely
the checksum conversion and no_check6_rx check.

Similar to the previous commit, we move the common processing to
an UDPv6 specific helper and call it from both edemux code path
and normal code path. In respect to the UDPv4, we need to add an
explicit check for non zero csum according to no_check6_rx value.

Reported-by: Jianlin Shi <jishi@redhat.com>
Suggested-by: Xin Long <lucien.xin@gmail.com>
Fixes: c9f2c1ae12 ("udp6: fix socket leak on early demux")
Fixes: 2abb7cdc0d ("udp: Add support for doing checksum unnecessary conversion")
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-09-16 15:27:44 -07:00
Martin KaFai Lau 8217ca653e bpf: Enable BPF_PROG_TYPE_SK_REUSEPORT bpf prog in reuseport selection
This patch allows a BPF_PROG_TYPE_SK_REUSEPORT bpf prog to select a
SO_REUSEPORT sk from a BPF_MAP_TYPE_REUSEPORT_ARRAY introduced in
the earlier patch.  "bpf_run_sk_reuseport()" will return -ECONNREFUSED
when the BPF_PROG_TYPE_SK_REUSEPORT prog returns SK_DROP.
The callers, in inet[6]_hashtable.c and ipv[46]/udp.c, are modified to
handle this case and return NULL immediately instead of continuing the
sk search from its hashtable.

It re-uses the existing SO_ATTACH_REUSEPORT_EBPF setsockopt to attach
BPF_PROG_TYPE_SK_REUSEPORT.  The "sk_reuseport_attach_bpf()" will check
if the attaching bpf prog is in the new SK_REUSEPORT or the existing
SOCKET_FILTER type and then check different things accordingly.

One level of "__reuseport_attach_prog()" call is removed.  The
"sk_unhashed() && ..." and "sk->sk_reuseport_cb" tests are pushed
back to "reuseport_attach_prog()" in sock_reuseport.c.  sock_reuseport.c
seems to have more knowledge on those test requirements than filter.c.
In "reuseport_attach_prog()", after new_prog is attached to reuse->prog,
the old_prog (if any) is also directly freed instead of returning the
old_prog to the caller and asking the caller to free.

The sysctl_optmem_max check is moved back to the
"sk_reuseport_attach_filter()" and "sk_reuseport_attach_bpf()".
As of other bpf prog types, the new BPF_PROG_TYPE_SK_REUSEPORT is only
bounded by the usual "bpf_prog_charge_memlock()" during load time
instead of bounded by both bpf_prog_charge_memlock and sysctl_optmem_max.

Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-08-11 01:58:46 +02:00
Willem de Bruijn 5fdaa88dfe ipv6: fold sockcm_cookie into ipcm6_cookie
ipcm_cookie includes sockcm_cookie. Do the same for ipcm6_cookie.

This reduces the number of arguments that need to be passed around,
applies ipcm6_init to all cookie fields at once and reduces code
differentiation between ipv4 and ipv6.

Signed-off-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-07 10:58:49 +09:00
Willem de Bruijn b515430ac9 ipv6: ipcm6_cookie initializer
Initialize the cookie in one location to reduce code duplication and
avoid bugs from inconsistent initialization, such as that fixed in
commit 9887cba199 ("ip: limit use of gso_size to udp").

Signed-off-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-07 10:58:49 +09:00
Jesus Sanchez-Palencia a818f75e31 net: ipv6: Hook into time based transmission
Add a struct sockcm_cookie parameter to ip6_setup_cork() so
we can easily re-use the transmit_time field from struct inet_cork
for most paths, by copying the timestamp from the CMSG cookie.
This is later copied into the skb during __ip6_make_skb().

For the raw fast path, also pass the sockcm_cookie as a parameter
so we can just perform the copy at rawv6_send_hdrinc() directly.

Signed-off-by: Jesus Sanchez-Palencia <jesus.sanchez-palencia@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-04 22:30:27 +09:00
Paolo Abeni 6c206b2009 udp: fix rx queue len reported by diag and proc interface
After commit 6b229cf77d ("udp: add batching to udp_rmem_release()")
the sk_rmem_alloc field does not measure exactly anymore the
receive queue length, because we batch the rmem release. The issue
is really apparent only after commit 0d4a6608f6 ("udp: do rmem bulk
free even if the rx sk queue is empty"): the user space can easily
check for an empty socket with not-0 queue length reported by the 'ss'
tool or the procfs interface.

We need to use a custom UDP helper to report the correct queue length,
taking into account the forward allocation deficit.

Reported-by: trevor.francis@46labs.com
Fixes: 6b229cf77d ("UDP: add batching to udp_rmem_release()")
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-06-08 19:55:15 -04:00
Linus Torvalds 1c8c5a9d38 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next
Pull networking updates from David Miller:

 1) Add Maglev hashing scheduler to IPVS, from Inju Song.

 2) Lots of new TC subsystem tests from Roman Mashak.

 3) Add TCP zero copy receive and fix delayed acks and autotuning with
    SO_RCVLOWAT, from Eric Dumazet.

 4) Add XDP_REDIRECT support to mlx5 driver, from Jesper Dangaard
    Brouer.

 5) Add ttl inherit support to vxlan, from Hangbin Liu.

 6) Properly separate ipv6 routes into their logically independant
    components. fib6_info for the routing table, and fib6_nh for sets of
    nexthops, which thus can be shared. From David Ahern.

 7) Add bpf_xdp_adjust_tail helper, which can be used to generate ICMP
    messages from XDP programs. From Nikita V. Shirokov.

 8) Lots of long overdue cleanups to the r8169 driver, from Heiner
    Kallweit.

 9) Add BTF ("BPF Type Format"), from Martin KaFai Lau.

10) Add traffic condition monitoring to iwlwifi, from Luca Coelho.

11) Plumb extack down into fib_rules, from Roopa Prabhu.

12) Add Flower classifier offload support to igb, from Vinicius Costa
    Gomes.

13) Add UDP GSO support, from Willem de Bruijn.

14) Add documentation for eBPF helpers, from Quentin Monnet.

15) Add TLS tx offload to mlx5, from Ilya Lesokhin.

16) Allow applications to be given the number of bytes available to read
    on a socket via a control message returned from recvmsg(), from
    Soheil Hassas Yeganeh.

17) Add x86_32 eBPF JIT compiler, from Wang YanQing.

18) Add AF_XDP sockets, with zerocopy support infrastructure as well.
    From Björn Töpel.

19) Remove indirect load support from all of the BPF JITs and handle
    these operations in the verifier by translating them into native BPF
    instead. From Daniel Borkmann.

20) Add GRO support to ipv6 gre tunnels, from Eran Ben Elisha.

21) Allow XDP programs to do lookups in the main kernel routing tables
    for forwarding. From David Ahern.

22) Allow drivers to store hardware state into an ELF section of kernel
    dump vmcore files, and use it in cxgb4. From Rahul Lakkireddy.

23) Various RACK and loss detection improvements in TCP, from Yuchung
    Cheng.

24) Add TCP SACK compression, from Eric Dumazet.

25) Add User Mode Helper support and basic bpfilter infrastructure, from
    Alexei Starovoitov.

26) Support ports and protocol values in RTM_GETROUTE, from Roopa
    Prabhu.

27) Support bulking in ->ndo_xdp_xmit() API, from Jesper Dangaard
    Brouer.

28) Add lots of forwarding selftests, from Petr Machata.

29) Add generic network device failover driver, from Sridhar Samudrala.

* ra.kernel.org:/pub/scm/linux/kernel/git/davem/net-next: (1959 commits)
  strparser: Add __strp_unpause and use it in ktls.
  rxrpc: Fix terminal retransmission connection ID to include the channel
  net: hns3: Optimize PF CMDQ interrupt switching process
  net: hns3: Fix for VF mailbox receiving unknown message
  net: hns3: Fix for VF mailbox cannot receiving PF response
  bnx2x: use the right constant
  Revert "net: sched: cls: Fix offloading when ingress dev is vxlan"
  net: dsa: b53: Fix for brcm tag issue in Cygnus SoC
  enic: fix UDP rss bits
  netdev-FAQ: clarify DaveM's position for stable backports
  rtnetlink: validate attributes in do_setlink()
  mlxsw: Add extack messages for port_{un, }split failures
  netdevsim: Add extack error message for devlink reload
  devlink: Add extack to reload and port_{un, }split operations
  net: metrics: add proper netlink validation
  ipmr: fix error path when ipmr_new_table fails
  ip6mr: only set ip6mr_table from setsockopt when ip6mr_new_table succeeds
  net: hns3: remove unused hclgevf_cfg_func_mta_filter
  netfilter: provide udp*_lib_lookup for nf_tproxy
  qed*: Utilize FW 8.37.2.0
  ...
2018-06-06 18:39:49 -07:00
David S. Miller fd129f8941 Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next
Daniel Borkmann says:

====================
pull-request: bpf-next 2018-06-05

The following pull-request contains BPF updates for your *net-next* tree.

The main changes are:

1) Add a new BPF hook for sendmsg similar to existing hooks for bind and
   connect: "This allows to override source IP (including the case when it's
   set via cmsg(3)) and destination IP:port for unconnected UDP (slow path).
   TCP and connected UDP (fast path) are not affected. This makes UDP support
   complete, that is, connected UDP is handled by connect hooks, unconnected
   by sendmsg ones.", from Andrey.

2) Rework of the AF_XDP API to allow extending it in future for type writer
   model if necessary. In this mode a memory window is passed to hardware
   and multiple frames might be filled into that window instead of just one
   that is the case in the current fixed frame-size model. With the new
   changes made this can be supported without having to add a new descriptor
   format. Also, core bits for the zero-copy support for AF_XDP have been
   merged as agreed upon, where i40e bits will be routed via Jeff later on.
   Various improvements to documentation and sample programs included as
   well, all from Björn and Magnus.

3) Given BPF's flexibility, a new program type has been added to implement
   infrared decoders. Quote: "The kernel IR decoders support the most
   widely used IR protocols, but there are many protocols which are not
   supported. [...] There is a 'long tail' of unsupported IR protocols,
   for which lircd is need to decode the IR. IR encoding is done in such
   a way that some simple circuit can decode it; therefore, BPF is ideal.
   [...] user-space can define a decoder in BPF, attach it to the rc
   device through the lirc chardev.", from Sean.

4) Several improvements and fixes to BPF core, among others, dumping map
   and prog IDs into fdinfo which is a straight forward way to correlate
   BPF objects used by applications, removing an indirect call and therefore
   retpoline in all map lookup/update/delete calls by invoking the callback
   directly for 64 bit archs, adding a new bpf_skb_cgroup_id() BPF helper
   for tc BPF programs to have an efficient way of looking up cgroup v2 id
   for policy or other use cases. Fixes to make sure we zero tunnel/xfrm
   state that hasn't been filled, to allow context access wrt pt_regs in
   32 bit archs for tracing, and last but not least various test cases
   for fixes that landed in bpf earlier, from Daniel.

5) Get rid of the ndo_xdp_flush API and extend the ndo_xdp_xmit with
   a XDP_XMIT_FLUSH flag instead which allows to avoid one indirect
   call as flushing is now merged directly into ndo_xdp_xmit(), from Jesper.

6) Add a new bpf_get_current_cgroup_id() helper that can be used in
   tracing to retrieve the cgroup id from the current process in order
   to allow for e.g. aggregation of container-level events, from Yonghong.

7) Two follow-up fixes for BTF to reject invalid input values and
   related to that also two test cases for BPF kselftests, from Martin.

8) Various API improvements to the bpf_fib_lookup() helper, that is,
   dropping MPLS bits which are not fully hashed out yet, rejecting
   invalid helper flags, returning error for unsupported address
   families as well as renaming flowlabel to flowinfo, from David.

9) Various fixes and improvements to sockmap BPF kselftests in particular
   in proper error detection and data verification, from Prashant.

10) Two arm32 BPF JIT improvements. One is to fix imm range check with
    regards to whether immediate fits into 24 bits, and a naming cleanup
    to get functions related to rsh handling consistent to those handling
    lsh, from Wang.

11) Two compile warning fixes in BPF, one for BTF and a false positive
    to silent gcc in stack_map_get_build_id_offset(), from Arnd.

12) Add missing seg6.h header into tools include infrastructure in order
    to fix compilation of BPF kselftests, from Mathieu.

13) Several formatting cleanups in the BPF UAPI helper description that
    also fix an error during rst2man compilation, from Quentin.

14) Hide an unused variable in sk_msg_convert_ctx_access() when IPv6 is
    not built into the kernel, from Yue.

15) Remove a useless double assignment in dev_map_enqueue(), from Colin.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-06-05 12:42:19 -04:00
Arnd Bergmann 6e86000c2c netfilter: provide udp*_lib_lookup for nf_tproxy
It is now possible to enable the libified nf_tproxy modules without
also enabling NETFILTER_XT_TARGET_TPROXY, which throws off the
ifdef logic in the udp core code:

net/ipv6/netfilter/nf_tproxy_ipv6.o: In function `nf_tproxy_get_sock_v6':
nf_tproxy_ipv6.c:(.text+0x1a8): undefined reference to `udp6_lib_lookup'
net/ipv4/netfilter/nf_tproxy_ipv4.o: In function `nf_tproxy_get_sock_v4':
nf_tproxy_ipv4.c:(.text+0x3d0): undefined reference to `udp4_lib_lookup'

We can actually simplify the conditions now to provide the two functions
exactly when they are needed.

Fixes: 45ca4e0cf2 ("netfilter: Libify xt_TPROXY")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Paolo Abeni <pabeni@redhat.com>
Acked-by: Máté Eckl <ecklm94@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-06-05 10:55:05 -04:00
Andrey Ignatov 1cedee13d2 bpf: Hooks for sys_sendmsg
In addition to already existing BPF hooks for sys_bind and sys_connect,
the patch provides new hooks for sys_sendmsg.

It leverages existing BPF program type `BPF_PROG_TYPE_CGROUP_SOCK_ADDR`
that provides access to socket itlself (properties like family, type,
protocol) and user-passed `struct sockaddr *` so that BPF program can
override destination IP and port for system calls such as sendto(2) or
sendmsg(2) and/or assign source IP to the socket.

The hooks are implemented as two new attach types:
`BPF_CGROUP_UDP4_SENDMSG` and `BPF_CGROUP_UDP6_SENDMSG` for UDPv4 and
UDPv6 correspondingly.

UDPv4 and UDPv6 separate attach types for same reason as sys_bind and
sys_connect hooks, i.e. to prevent reading from / writing to e.g.
user_ip6 fields when user passes sockaddr_in since it'd be out-of-bound.

The difference with already existing hooks is sys_sendmsg are
implemented only for unconnected UDP.

For TCP it doesn't make sense to change user-provided `struct sockaddr *`
at sendto(2)/sendmsg(2) time since socket either was already connected
and has source/destination set or wasn't connected and call to
sendto(2)/sendmsg(2) would lead to ENOTCONN anyway.

Connected UDP is already handled by sys_connect hooks that can override
source/destination at connect time and use fast-path later, i.e. these
hooks don't affect UDP fast-path.

Rewriting source IP is implemented differently than that in sys_connect
hooks. When sys_sendmsg is used with unconnected UDP it doesn't work to
just bind socket to desired local IP address since source IP can be set
on per-packet basis by using ancillary data (cmsg(3)). So no matter if
socket is bound or not, source IP has to be rewritten on every call to
sys_sendmsg.

To do so two new fields are added to UAPI `struct bpf_sock_addr`;
* `msg_src_ip4` to set source IPv4 for UDPv4;
* `msg_src_ip6` to set source IPv6 for UDPv6.

Signed-off-by: Andrey Ignatov <rdna@fb.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-05-28 17:41:02 +02:00
Willem de Bruijn ff06342cbc udp: exclude gso from xfrm paths
UDP GSO delays final datagram construction to the GSO layer. This
conflicts with protocol transformations.

Fixes: bec1f6f697 ("udp: generate gso with UDP_SEGMENT")
CC: Michal Kubecek <mkubecek@suse.cz>
Signed-off-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-05-23 14:48:44 -04:00
Christoph Hellwig c350637227 proc: introduce proc_create_net{,_data}
Variants of proc_create{,_data} that directly take a struct seq_operations
and deal with network namespaces in ->open and ->release.  All callers of
proc_create + seq_open_net converted over, and seq_{open,release}_net are
removed entirely.

Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-05-16 07:24:30 +02:00
Christoph Hellwig a3d2599b24 ipv{4,6}/udp{,lite}: simplify proc registration
Remove a couple indirections to make the code look like most other
protocols.

Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-05-16 07:23:35 +02:00