Commit Graph

822 Commits

Author SHA1 Message Date
Willem de Bruijn 185ce5c38e net: test nouarg before dereferencing zerocopy pointers
Zerocopy skbs without completion notification were added for packet
sockets with PACKET_TX_RING user buffers. Those signal completion
through the TP_STATUS_USER bit in the ring. Zerocopy annotation was
added only to avoid premature notification after clone or orphan, by
triggering a copy on these paths for these packets.

The mechanism had to define a special "no-uarg" mode because packet
sockets already use skb_uarg(skb) == skb_shinfo(skb)->destructor_arg
for a different pointer.

Before deferencing skb_uarg(skb), verify that it is a real pointer.

Fixes: 5cd8d46ea1 ("packet: copy user buffers before orphan or clone")
Signed-off-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-05-16 12:17:50 -07:00
Stanislav Fomichev 118c8e9ae6 bpf: support BPF_PROG_QUERY for BPF_FLOW_DISSECTOR attach_type
target_fd is target namespace. If there is a flow dissector BPF program
attached to that namespace, its (single) id is returned.

v5:
* drop net ref right after rcu unlock (Daniel Borkmann)

v4:
* add missing put_net (Jann Horn)

v3:
* add missing inline to skb_flow_dissector_prog_query static def
  (kbuild test robot <lkp@intel.com>)

v2:
* don't sleep in rcu critical section (Jakub Kicinski)
* check input prog_cnt (exit early)

Cc: Jann Horn <jannh@google.com>
Signed-off-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2019-04-25 23:49:06 +02:00
Stanislav Fomichev 9b52e3f267 flow_dissector: handle no-skb use case
When called without skb, gather all required data from the
__skb_flow_dissect's arguments and use recently introduces
no-skb mode of bpf flow dissector.

Note: WARN_ON_ONCE(!net) will now trigger for eth_get_headlen users.

Signed-off-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2019-04-23 18:36:34 +02:00
Stanislav Fomichev 3cbf4ffba5 net: plumb network namespace into __skb_flow_dissect
This new argument will be used in the next patches for the
eth_get_headlen use case. eth_get_headlen calls flow dissector
with only data (without skb) so there is currently no way to
pull attached BPF flow dissector program. With this new argument,
we can amend the callers to explicitly pass network namespace
so we can use attached BPF program.

Signed-off-by: Stanislav Fomichev <sdf@google.com>
Reviewed-by: Saeed Mahameed <saeedm@mellanox.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2019-04-23 18:36:34 +02:00
Stanislav Fomichev 089b19a920 flow_dissector: switch kernel context to struct bpf_flow_dissector
struct bpf_flow_dissector has a small subset of sk_buff fields that
flow dissector BPF program is allowed to access and an optional
pointer to real skb. Real skb is used only in bpf_skb_load_bytes
helper to read non-linear data.

The real motivation for this is to be able to call flow dissector
from eth_get_headlen context where we don't have an skb and need
to dissect raw bytes.

Signed-off-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2019-04-23 18:36:33 +02:00
David S. Miller 2843ba2ec7 Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next
Alexei Starovoitov says:

====================
pull-request: bpf-next 2019-04-22

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

The main changes are:

1) allow stack/queue helpers from more bpf program types, from Alban.

2) allow parallel verification of root bpf programs, from Alexei.

3) introduce bpf sysctl hook for trusted root cases, from Andrey.

4) recognize var/datasec in btf deduplication, from Andrii.

5) cpumap performance optimizations, from Jesper.

6) verifier prep for alu32 optimization, from Jiong.

7) libbpf xsk cleanup, from Magnus.

8) other various fixes and cleanups.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2019-04-22 21:35:55 -07:00
Jakub Kicinski a06eaaf791 net: skb: remove unused asserts
We are discouraging the use of BUG() these days, remove the
unused ASSERT macros from skbuff.h.

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Dirk van der Merwe <dirk.vandermerwe@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-04-18 17:06:15 -07:00
Jesper Dangaard Brouer ba0509b688 net: core: introduce build_skb_around
The function build_skb() also have the responsibility to allocate and clear
the SKB structure. Introduce a new function build_skb_around(), that moves
the responsibility of allocation and clearing to the caller. This allows
caller to use kmem_cache (slab/slub) bulk allocation API.

Next patch use this function combined with kmem_cache_alloc_bulk.

Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Acked-by: Song Liu <songliubraving@fb.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2019-04-17 19:09:24 -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
Florian Westphal 4f296edeb9 drivers: net: aurora: use netdev_xmit_more helper
This is the last driver using always-0 skb->xmit_more.
Switch it to netdev_xmit_more and remove the now unused xmit_more flag
from sk_buff.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-04-01 18:35:02 -07:00
Linus Torvalds 8f49a658b4 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Pull networking fixes from David Miller:
 "First batch of fixes in the new merge window:

   1) Double dst_cache free in act_tunnel_key, from Wenxu.

   2) Avoid NULL deref in IN_DEV_MFORWARD() by failing early in the
      ip_route_input_rcu() path, from Paolo Abeni.

   3) Fix appletalk compile regression, from Arnd Bergmann.

   4) If SLAB objects reach the TCP sendpage method we are in serious
      trouble, so put a debugging check there. From Vasily Averin.

   5) Memory leak in hsr layer, from Mao Wenan.

   6) Only test GSO type on GSO packets, from Willem de Bruijn.

   7) Fix crash in xsk_diag_put_umem(), from Eric Dumazet.

   8) Fix VNIC mailbox length in nfp, from Dirk van der Merwe.

   9) Fix race in ipv4 route exception handling, from Xin Long.

  10) Missing DMA memory barrier in hns3 driver, from Jian Shen.

  11) Use after free in __tcf_chain_put(), from Vlad Buslov.

  12) Handle inet_csk_reqsk_queue_add() failures, from Guillaume Nault.

  13) Return value correction when ip_mc_may_pull() fails, from Eric
      Dumazet.

  14) Use after free in x25_device_event(), also from Eric"

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (72 commits)
  gro_cells: make sure device is up in gro_cells_receive()
  vxlan: test dev->flags & IFF_UP before calling gro_cells_receive()
  net/x25: fix use-after-free in x25_device_event()
  isdn: mISDNinfineon: fix potential NULL pointer dereference
  net: hns3: fix to stop multiple HNS reset due to the AER changes
  ip: fix ip_mc_may_pull() return value
  net: keep refcount warning in reqsk_free()
  net: stmmac: Avoid one more sometimes uninitialized Clang warning
  net: dsa: mv88e6xxx: Set correct interface mode for CPU/DSA ports
  rxrpc: Fix client call queueing, waiting for channel
  tcp: handle inet_csk_reqsk_queue_add() failures
  net: ethernet: sun: Zero initialize class in default case in niu_add_ethtool_tcam_entry
  8139too : Add support for U.S. Robotics USR997901A 10/100 Cardbus NIC
  fou, fou6: avoid uninit-value in gue_err() and gue6_err()
  net: sched: fix potential use-after-free in __tcf_chain_put()
  vhost: silence an unused-variable warning
  vsock/virtio: fix kernel panic from virtio_transport_reset_no_sock
  connector: fix unsafe usage of ->real_parent
  vxlan: do not need BH again in vxlan_cleanup()
  net: hns3: add dma_rmb() for rx description
  ...
2019-03-11 08:54:01 -07:00
Linus Torvalds 1a29e85750 A fairly routine cycle for docs - lots of typo fixes, some new documents,
and more translations.  There's also some LICENSES adjustments from
 Thomas.
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Merge tag 'docs-5.1' of git://git.lwn.net/linux

Pull documentation updates from Jonathan Corbet:
 "A fairly routine cycle for docs - lots of typo fixes, some new
  documents, and more translations. There's also some LICENSES
  adjustments from Thomas"

* tag 'docs-5.1' of git://git.lwn.net/linux: (74 commits)
  docs: Bring some order to filesystem documentation
  Documentation/locking/lockdep: Drop last two chars of sample states
  doc: rcu: Suspicious RCU usage is a warning
  docs: driver-api: iio: fix errors in documentation
  Documentation/process/howto: Update for 4.x -> 5.x versioning
  docs: Explicitly state that the 'Fixes:' tag shouldn't split lines
  doc: security: Add kern-doc for lsm_hooks.h
  doc: sctp: Merge and clean up rst files
  Docs: Correct /proc/stat path
  scripts/spdxcheck.py: fix C++ comment style detection
  doc: fix typos in license-rules.rst
  Documentation: fix admin-guide/README.rst minimum gcc version requirement
  doc: process: complete removal of info about -git patches
  doc: translations: sync translations 'remove info about -git patches'
  perf-security: wrap paragraphs on 72 columns
  perf-security: elaborate on perf_events/Perf privileged users
  perf-security: document collected perf_events/Perf data categories
  perf-security: document perf_events/Perf resource control
  sysfs.txt: add note on available attribute macros
  docs: kernel-doc: typo "if ... if" -> "if ... is"
  ...
2019-03-09 09:56:17 -08:00
David S. Miller c3ad3eca2f Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf
Daniel Borkmann says:

====================
pull-request: bpf 2019-03-09

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

The main changes are:

1) Fix a crash in AF_XDP's xsk_diag_put_ring() which was passing
   wrong queue argument, from Eric.

2) Fix a regression due to wrong test for TCP GSO packets used in
   various BPF helpers like NAT64, from Willem.

3) Fix a sk_msg strparser warning which asserts that strparser must
   be stopped first, from Jakub.

4) Fix rejection of invalid options/bind flags in AF_XDP, from Björn.

5) Fix GSO in bpf_lwt_push_ip_encap() which must properly set inner
   headers and inner protocol, from Peter.

6) Fix a libbpf leak when kernel does not support BTF, from Nikita.

7) Various BPF selftest and libbpf build fixes to make out-of-tree
   compilation work and to properly resolve dependencies via fixdep
   target, from Stanislav.

8) Fix rejection of invalid ldimm64 imm field, from Daniel.

9) Fix bpf stats sysctl compile warning of unused helper function
   proc_dointvec_minmax_bpf_stats() under some configs, from Arnd.

10) Fix couple of warnings about using plain integer as NULL, from Bo.

11) Fix some BPF sample spelling mistakes, from Colin.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2019-03-08 18:23:29 -08:00
Pedro Tammela 161e613755 net: add missing documentation in linux/skbuff.h
This patch adds missing documentation for some inline functions on
linux/skbuff.h. The patch is incomplete and a lot more can be added,
just wondering if it's of interest of the netdev developers.

Also fixed some whitespaces.

Signed-off-by: Pedro Tammela <pctammela@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-03-08 14:38:19 -08:00
Willem de Bruijn 4c3024debf bpf: only test gso type on gso packets
BPF can adjust gso only for tcp bytestreams. Fail on other gso types.

But only on gso packets. It does not touch this field if !gso_size.

Fixes: b90efd2258 ("bpf: only adjust gso_size on bytestream protocols")
Signed-off-by: Willem de Bruijn <willemb@google.com>
Acked-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2019-03-07 10:32:24 +01:00
Maxim Mikityanskiy d2aa125d62 net: Don't set transport offset to invalid value
If the socket was created with socket(AF_PACKET, SOCK_RAW, 0),
skb->protocol will be unset, __skb_flow_dissect() will fail, and
skb_probe_transport_header() will fall back to the offset_hint, making
the resulting skb_transport_offset incorrect.

If, however, there is no transport header in the packet,
transport_header shouldn't be set to an arbitrary value.

Fix it by leaving the transport offset unset if it couldn't be found, to
be explicit rather than to fill it with some wrong value. It changes the
behavior, but if some code relied on the old behavior, it would be
broken anyway, as the old one is incorrect.

Signed-off-by: Maxim Mikityanskiy <maximmi@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-02-22 12:55:31 -08:00
David S. Miller 375ca548f7 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Two easily resolvable overlapping change conflicts, one in
TCP and one in the eBPF verifier.

Signed-off-by: David S. Miller <davem@davemloft.net>
2019-02-20 00:34:07 -08:00
David S. Miller 6e1077f514 Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf
Alexei Starovoitov says:

====================
pull-request: bpf 2019-02-16

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

The main changes are:

1) fix lockdep false positive in bpf_get_stackid(), from Alexei.

2) several AF_XDP fixes, from Bjorn, Magnus, Davidlohr.

3) fix narrow load from struct bpf_sock, from Martin.

4) mips JIT fixes, from Paul.

5) gso handling fix in bpf helpers, from Willem.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2019-02-16 22:34:07 -08:00
Willem de Bruijn d5be7f632b net: validate untrusted gso packets without csum offload
Syzkaller again found a path to a kernel crash through bad gso input.
By building an excessively large packet to cause an skb field to wrap.

If VIRTIO_NET_HDR_F_NEEDS_CSUM was set this would have been dropped in
skb_partial_csum_set.

GSO packets that do not set checksum offload are suspicious and rare.
Most callers of virtio_net_hdr_to_skb already pass them to
skb_probe_transport_header.

Move that test forward, change it to detect parse failure and drop
packets on failure as those cleary are not one of the legitimate
VIRTIO_NET_HDR_GSO types.

Fixes: bfd5f4a3d6 ("packet: Add GSO/csum offload support.")
Fixes: f43798c276 ("tun: Allow GSO using virtio_net_hdr")
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: Willem de Bruijn <willemb@google.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-02-15 20:30:37 -08:00
Brian Norris 4ea7b0cf0d net/skbuff: fix up kernel-doc placement
There are several skb_* functions where the locked and unlocked
functions are confusingly documented. For several of them, the
kernel-doc for the unlocked version is placed above the locked version,
which to the casual reader makes it seems like the locked version "takes
no locks and you must therefore hold required locks before calling it."

One can see, for example, that this link claims to document
skb_queue_head(), while instead describing __skb_queue_head().

https://www.kernel.org/doc/html/latest/networking/kapi.html#c.skb_queue_head

The correct documentation for skb_queue_head() is also included further
down the page.

This diff tested via:

  $ scripts/kernel-doc -rst include/linux/skbuff.h net/core/skbuff.c

No new warnings were seen, and the output makes a little more sense.

Signed-off-by: Brian Norris <briannorris@chromium.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-02-12 12:54:37 -05:00
Willem de Bruijn b90efd2258 bpf: only adjust gso_size on bytestream protocols
bpf_skb_change_proto and bpf_skb_adjust_room change skb header length.
For GSO packets they adjust gso_size to maintain the same MTU.

The gso size can only be safely adjusted on bytestream protocols.
Commit d02f51cbcf ("bpf: fix bpf_skb_adjust_net/bpf_skb_proto_xlat
to deal with gso sctp skbs") excluded SKB_GSO_SCTP.

Since then type SKB_GSO_UDP_L4 has been added, whose contents are one
gso_size unit per datagram. Also exclude these.

Move from a blacklist to a whitelist check to future proof against
additional such new GSO types, e.g., for fraglist based GRO.

Fixes: bec1f6f697 ("udp: generate gso with UDP_SEGMENT")
Signed-off-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2019-02-10 19:57:34 -08:00
Deepa Dinamani 887feae36a socket: Add SO_TIMESTAMP[NS]_NEW
Add SO_TIMESTAMP_NEW and SO_TIMESTAMPNS_NEW variants of
socket timestamp options.
These are the y2038 safe versions of the SO_TIMESTAMP_OLD
and SO_TIMESTAMPNS_OLD for all architectures.

Note that the format of scm_timestamping.ts[0] is not changed
in this patch.

Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com>
Acked-by: Willem de Bruijn <willemb@google.com>
Cc: jejb@parisc-linux.org
Cc: ralf@linux-mips.org
Cc: rth@twiddle.net
Cc: linux-alpha@vger.kernel.org
Cc: linux-mips@linux-mips.org
Cc: linux-parisc@vger.kernel.org
Cc: linux-rdma@vger.kernel.org
Cc: netdev@vger.kernel.org
Cc: sparclinux@vger.kernel.org
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-02-03 11:17:31 -08:00
Deepa Dinamani 13c6ee2a92 socket: Use old_timeval types for socket timestamps
As part of y2038 solution, all internal uses of
struct timeval are replaced by struct __kernel_old_timeval
and struct compat_timeval by struct old_timeval32.
Make socket timestamps use these new types.

This is mainly to be able to verify that the kernel build
is y2038 safe when such non y2038 safe types are not
supported anymore.

Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com>
Acked-by: Willem de Bruijn <willemb@google.com>
Cc: isdn@linux-pingi.de
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-02-03 11:17:30 -08:00
David S. Miller ec7146db15 Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next
Daniel Borkmann says:

====================
pull-request: bpf-next 2019-01-29

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

The main changes are:

1) Teach verifier dead code removal, this also allows for optimizing /
   removing conditional branches around dead code and to shrink the
   resulting image. Code store constrained architectures like nfp would
   have hard time doing this at JIT level, from Jakub.

2) Add JMP32 instructions to BPF ISA in order to allow for optimizing
   code generation for 32-bit sub-registers. Evaluation shows that this
   can result in code reduction of ~5-20% compared to 64 bit-only code
   generation. Also add implementation for most JITs, from Jiong.

3) Add support for __int128 types in BTF which is also needed for
   vmlinux's BTF conversion to work, from Yonghong.

4) Add a new command to bpftool in order to dump a list of BPF-related
   parameters from the system or for a specific network device e.g. in
   terms of available prog/map types or helper functions, from Quentin.

5) Add AF_XDP sock_diag interface for querying sockets from user
   space which provides information about the RX/TX/fill/completion
   rings, umem, memory usage etc, from Björn.

6) Add skb context access for skb_shared_info->gso_segs field, from Eric.

7) Add support for testing flow dissector BPF programs by extending
   existing BPF_PROG_TEST_RUN infrastructure, from Stanislav.

8) Split BPF kselftest's test_verifier into various subgroups of tests
   in order better deal with merge conflicts in this area, from Jakub.

9) Add support for queue/stack manipulations in bpftool, from Stanislav.

10) Document BTF, from Yonghong.

11) Dump supported ELF section names in libbpf on program load
    failure, from Taeung.

12) Silence a false positive compiler warning in verifier's BTF
    handling, from Peter.

13) Fix help string in bpftool's feature probing, from Prashant.

14) Remove duplicate includes in BPF kselftests, from Yue.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2019-01-28 19:38:33 -08:00
Stanislav Fomichev c8aa703822 net/flow_dissector: move bpf case into __skb_flow_bpf_dissect
This way, we can reuse it for flow dissector in BPF_PROG_TEST_RUN.

No functional changes.

Signed-off-by: Stanislav Fomichev <sdf@google.com>
Acked-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2019-01-29 01:08:29 +01:00
Ross Lagerwall 6c57f04580 net: Fix usage of pskb_trim_rcsum
In certain cases, pskb_trim_rcsum() may change skb pointers.
Reinitialize header pointers afterwards to avoid potential
use-after-frees. Add a note in the documentation of
pskb_trim_rcsum(). Found by KASAN.

Signed-off-by: Ross Lagerwall <ross.lagerwall@citrix.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-01-18 14:05:14 -08:00
Otto Sabart d0dcde6426 doc: networking: convert offload files into RST and update references
This patch renames offload files. This is necessary for Sphinx.

Also update reference to checksum-offloads.rst file.

Whole kernel code was grepped for references using:
$ grep -r "\(segmentation\|checksum\)-offloads.txt" .

There should be no other references
to {segmentation,checksum}-offloads.txt files.

Signed-off-by: Otto Sabart <ottosabart@seberm.com>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2019-01-07 15:27:34 -07:00
Linus Torvalds 0e9da3fbf7 for-4.21/block-20181221
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Merge tag 'for-4.21/block-20181221' of git://git.kernel.dk/linux-block

Pull block updates from Jens Axboe:
 "This is the main pull request for block/storage for 4.21.

  Larger than usual, it was a busy round with lots of goodies queued up.
  Most notable is the removal of the old IO stack, which has been a long
  time coming. No new features for a while, everything coming in this
  week has all been fixes for things that were previously merged.

  This contains:

   - Use atomic counters instead of semaphores for mtip32xx (Arnd)

   - Cleanup of the mtip32xx request setup (Christoph)

   - Fix for circular locking dependency in loop (Jan, Tetsuo)

   - bcache (Coly, Guoju, Shenghui)
      * Optimizations for writeback caching
      * Various fixes and improvements

   - nvme (Chaitanya, Christoph, Sagi, Jay, me, Keith)
      * host and target support for NVMe over TCP
      * Error log page support
      * Support for separate read/write/poll queues
      * Much improved polling
      * discard OOM fallback
      * Tracepoint improvements

   - lightnvm (Hans, Hua, Igor, Matias, Javier)
      * Igor added packed metadata to pblk. Now drives without metadata
        per LBA can be used as well.
      * Fix from Geert on uninitialized value on chunk metadata reads.
      * Fixes from Hans and Javier to pblk recovery and write path.
      * Fix from Hua Su to fix a race condition in the pblk recovery
        code.
      * Scan optimization added to pblk recovery from Zhoujie.
      * Small geometry cleanup from me.

   - Conversion of the last few drivers that used the legacy path to
     blk-mq (me)

   - Removal of legacy IO path in SCSI (me, Christoph)

   - Removal of legacy IO stack and schedulers (me)

   - Support for much better polling, now without interrupts at all.
     blk-mq adds support for multiple queue maps, which enables us to
     have a map per type. This in turn enables nvme to have separate
     completion queues for polling, which can then be interrupt-less.
     Also means we're ready for async polled IO, which is hopefully
     coming in the next release.

   - Killing of (now) unused block exports (Christoph)

   - Unification of the blk-rq-qos and blk-wbt wait handling (Josef)

   - Support for zoned testing with null_blk (Masato)

   - sx8 conversion to per-host tag sets (Christoph)

   - IO priority improvements (Damien)

   - mq-deadline zoned fix (Damien)

   - Ref count blkcg series (Dennis)

   - Lots of blk-mq improvements and speedups (me)

   - sbitmap scalability improvements (me)

   - Make core inflight IO accounting per-cpu (Mikulas)

   - Export timeout setting in sysfs (Weiping)

   - Cleanup the direct issue path (Jianchao)

   - Export blk-wbt internals in block debugfs for easier debugging
     (Ming)

   - Lots of other fixes and improvements"

* tag 'for-4.21/block-20181221' of git://git.kernel.dk/linux-block: (364 commits)
  kyber: use sbitmap add_wait_queue/list_del wait helpers
  sbitmap: add helpers for add/del wait queue handling
  block: save irq state in blkg_lookup_create()
  dm: don't reuse bio for flushes
  nvme-pci: trace SQ status on completions
  nvme-rdma: implement polling queue map
  nvme-fabrics: allow user to pass in nr_poll_queues
  nvme-fabrics: allow nvmf_connect_io_queue to poll
  nvme-core: optionally poll sync commands
  block: make request_to_qc_t public
  nvme-tcp: fix spelling mistake "attepmpt" -> "attempt"
  nvme-tcp: fix endianess annotations
  nvmet-tcp: fix endianess annotations
  nvme-pci: refactor nvme_poll_irqdisable to make sparse happy
  nvme-pci: only set nr_maps to 2 if poll queues are supported
  nvmet: use a macro for default error location
  nvmet: fix comparison of a u16 with -1
  blk-mq: enable IO poll if .nr_queues of type poll > 0
  blk-mq: change blk_mq_queue_busy() to blk_mq_queue_inflight()
  blk-mq: skip zero-queue maps in blk_mq_map_swqueue
  ...
2018-12-28 13:19:59 -08:00
Paolo Abeni d312d0a684 net: drop the unused helper skb_ext_get()
Such helper is currently unused, and skb extension users are
better off using skb_ext_add()/skb_ext_del(). So let's drop
it.

Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Acked-by: Florian Westphal <fw@strlen.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-12-21 10:24:54 -08:00
Florian Westphal 4165079ba3 net: switch secpath to use skb extension infrastructure
Remove skb->sp and allocate secpath storage via extension
infrastructure.  This also reduces sk_buff by 8 bytes on x86_64.

Total size of allyesconfig kernel is reduced slightly, as there is
less inlined code (one conditional atomic op instead of two on
skb_clone).

No differences in throughput in following ipsec performance tests:
- transport mode with aes on 10GB link
- tunnel mode between two network namespaces with aes and null cipher

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-12-19 11:21:38 -08:00
Florian Westphal 2294be0f11 net: use skb_sec_path helper in more places
skb_sec_path gains 'const' qualifier to avoid
xt_policy.c: 'skb_sec_path' discards 'const' qualifier from pointer target type

same reasoning as previous conversions: Won't need to touch these
spots anymore when skb->sp is removed.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-12-19 11:21:37 -08:00
Florian Westphal 7af8f4ca31 net: move secpath_exist helper to sk_buff.h
Future patch will remove skb->sp pointer.
To reduce noise in those patches, move existing helper to
sk_buff and use it in more places to ease skb->sp replacement later.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-12-19 11:21:37 -08:00
Florian Westphal de8bda1d22 net: convert bridge_nf to use skb extension infrastructure
This converts the bridge netfilter (calling iptables hooks from bridge)
facility to use the extension infrastructure.

The bridge_nf specific hooks in skb clone and free paths are removed, they
have been replaced by the skb_ext hooks that do the same as the bridge nf
allocations hooks did.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-12-19 11:21:37 -08:00
Florian Westphal df5042f4c5 sk_buff: add skb extension infrastructure
This adds an optional extension infrastructure, with ispec (xfrm) and
bridge netfilter as first users.
objdiff shows no changes if kernel is built without xfrm and br_netfilter
support.

The third (planned future) user is Multipath TCP which is still
out-of-tree.
MPTCP needs to map logical mptcp sequence numbers to the tcp sequence
numbers used by individual subflows.

This DSS mapping is read/written from tcp option space on receive and
written to tcp option space on transmitted tcp packets that are part of
and MPTCP connection.

Extending skb_shared_info or adding a private data field to skb fclones
doesn't work for incoming skb, so a different DSS propagation method would
be required for the receive side.

mptcp has same requirements as secpath/bridge netfilter:

1. extension memory is released when the sk_buff is free'd.
2. data is shared after cloning an skb (clone inherits extension)
3. adding extension to an skb will COW the extension buffer if needed.

The "MPTCP upstreaming" effort adds SKB_EXT_MPTCP extension to store the
mapping for tx and rx processing.

Two new members are added to sk_buff:
1. 'active_extensions' byte (filling a hole), telling which extensions
   are available for this skb.
   This has two purposes.
   a) avoids the need to initialize the pointer.
   b) allows to "delete" an extension by clearing its bit
   value in ->active_extensions.

   While it would be possible to store the active_extensions byte
   in the extension struct instead of sk_buff, there is one problem
   with this:
    When an extension has to be disabled, we can always clear the
    bit in skb->active_extensions.  But in case it would be stored in the
    extension buffer itself, we might have to COW it first, if
    we are dealing with a cloned skb.  On kmalloc failure we would
    be unable to turn an extension off.

2. extension pointer, located at the end of the sk_buff.
   If the active_extensions byte is 0, the pointer is undefined,
   it is not initialized on skb allocation.

This adds extra code to skb clone and free paths (to deal with
refcount/free of extension area) but this replaces similar code that
manages skb->nf_bridge and skb->sp structs in the followup patches of
the series.

It is possible to add support for extensions that are not preseved on
clones/copies.

To do this, it would be needed to define a bitmask of all extensions that
need copy/cow semantics, and change __skb_ext_copy() to check
->active_extensions & SKB_EXT_PRESERVE_ON_CLONE, then just set
->active_extensions to 0 on the new clone.

This isn't done here because all extensions that get added here
need the copy/cow semantics.

v2:
Allocate entire extension space using kmem_cache.
Upside is that this allows better tracking of used memory,
downside is that we will allocate more space than strictly needed in
most cases (its unlikely that all extensions are active/needed at same
time for same skb).
The allocated memory (except the small extension header) is not cleared,
so no additonal overhead aside from memory usage.

Avoid atomic_dec_and_test operation on skb_ext_put()
by using similar trick as kfree_skbmem() does with fclone_ref:
If recount is 1, there is no concurrent user and we can free right away.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-12-19 11:21:37 -08:00
Sagi Grimberg 65d69e2505 datagram: introduce skb_copy_and_hash_datagram_iter helper
Introduce a helper to copy datagram into an iovec iterator
but also update a predefined hash. This is useful for
consumers of skb_copy_datagram_iter to also support inflight
data digest without having to finish to copy and only then
traverse the iovec and calculate the digest hash.

Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sagi Grimberg <sagi@lightbitslabs.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-12-13 09:58:55 +01:00
Ido Schimmel 875e893995 skbuff: Rename 'offload_mr_fwd_mark' to 'offload_l3_fwd_mark'
Commit abf4bb6b63 ("skbuff: Add the offload_mr_fwd_mark field") added
the 'offload_mr_fwd_mark' field to indicate that a packet has already
undergone L3 multicast routing by a capable device. The field is used to
prevent the kernel from forwarding a packet through a netdev through
which the device has already forwarded the packet.

Currently, no unicast packet is routed by both the device and the
kernel, but this is about to change by subsequent patches and we need to
be able to mark such packets, so that they will no be forwarded twice.

Instead of adding yet another field to 'struct sk_buff', we can just
rename 'offload_mr_fwd_mark' to 'offload_l3_fwd_mark', as a packet
either has a multicast or a unicast destination IP.

While at it, add a comment about both 'offload_fwd_mark' and
'offload_l3_fwd_mark'.

Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-12-04 08:36:36 -08:00
Willem de Bruijn 52900d2228 udp: elide zerocopy operation in hot path
With MSG_ZEROCOPY, each skb holds a reference to a struct ubuf_info.
Release of its last reference triggers a completion notification.

The TCP stack in tcp_sendmsg_locked holds an extra ref independent of
the skbs, because it can build, send and free skbs within its loop,
possibly reaching refcount zero and freeing the ubuf_info too soon.

The UDP stack currently also takes this extra ref, but does not need
it as all skbs are sent after return from __ip(6)_append_data.

Avoid the extra refcount_inc and refcount_dec_and_test, and generally
the sock_zerocopy_put in the common path, by passing the initial
reference to the first skb.

This approach is taken instead of initializing the refcount to 0, as
that would generate error "refcount_t: increment on 0" on the
next skb_zcopy_set.

Changes
  v3 -> v4
    - Move skb_zcopy_set below the only kfree_skb that might cause
      a premature uarg destroy before skb_zerocopy_put_abort
      - Move the entire skb_shinfo assignment block, to keep that
        cacheline access in one place

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>
2018-12-03 15:58:32 -08:00
Willem de Bruijn b5947e5d1e udp: msg_zerocopy
Extend zerocopy to udp sockets. Allow setting sockopt SO_ZEROCOPY and
interpret flag MSG_ZEROCOPY.

This patch was previously part of the zerocopy RFC patchsets. Zerocopy
is not effective at small MTU. With segmentation offload building
larger datagrams, the benefit of page flipping outweights the cost of
generating a completion notification.

tools/testing/selftests/net/msg_zerocopy.sh after applying follow-on
test patch and making skb_orphan_frags_rx same as skb_orphan_frags:

    ipv4 udp -t 1
    tx=191312 (11938 MB) txc=0 zc=n
    rx=191312 (11938 MB)
    ipv4 udp -z -t 1
    tx=304507 (19002 MB) txc=304507 zc=y
    rx=304507 (19002 MB)
    ok
    ipv6 udp -t 1
    tx=174485 (10888 MB) txc=0 zc=n
    rx=174485 (10888 MB)
    ipv6 udp -z -t 1
    tx=294801 (18396 MB) txc=294801 zc=y
    rx=294801 (18396 MB)
    ok

Changes
  v1 -> v2
    - Fixup reverse christmas tree violation
  v2 -> v3
    - Split refcount avoidance optimization into separate patch
      - Fix refcount leak on error in fragmented case
        (thanks to Paolo Abeni for pointing this one out!)
      - Fix refcount inc on zero
      - Test sock_flag SOCK_ZEROCOPY directly in __ip_append_data.
        This is needed since commit 5cf4a8532c ("tcp: really ignore
	MSG_ZEROCOPY if no SO_ZEROCOPY") did the same for tcp.

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>
2018-12-03 15:58:32 -08:00
Eric Dumazet 4bffc669d6 net: remove unsafe skb_insert()
I do not see how one can effectively use skb_insert() without holding
some kind of lock. Otherwise other cpus could have changed the list
right before we have a chance of acquiring list->lock.

Only existing user is in drivers/infiniband/hw/nes/nes_mgt.c and this
one probably meant to use __skb_insert() since it appears nesqp->pau_list
is protected by nesqp->pau_lock. This looks like nesqp->pau_lock
could be removed, since nesqp->pau_list.lock could be used instead.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Faisal Latif <faisal.latif@intel.com>
Cc: Doug Ledford <dledford@redhat.com>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: linux-rdma <linux-rdma@vger.kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-11-25 10:36:19 -08:00
David S. Miller b1bf78bfb2 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2018-11-24 17:01:43 -08:00
Willem de Bruijn 5cd8d46ea1 packet: copy user buffers before orphan or clone
tpacket_snd sends packets with user pages linked into skb frags. It
notifies that pages can be reused when the skb is released by setting
skb->destructor to tpacket_destruct_skb.

This can cause data corruption if the skb is orphaned (e.g., on
transmit through veth) or cloned (e.g., on mirror to another psock).

Create a kernel-private copy of data in these cases, same as tun/tap
zerocopy transmission. Reuse that infrastructure: mark the skb as
SKBTX_ZEROCOPY_FRAG, which will trigger copy in skb_orphan_frags(_rx).

Unlike other zerocopy packets, do not set shinfo destructor_arg to
struct ubuf_info. tpacket_destruct_skb already uses that ptr to notify
when the original skb is released and a timestamp is recorded. Do not
change this timestamp behavior. The ubuf_info->callback is not needed
anyway, as no zerocopy notification is expected.

Mark destructor_arg as not-a-uarg by setting the lower bit to 1. The
resulting value is not a valid ubuf_info pointer, nor a valid
tpacket_snd frame address. Add skb_zcopy_.._nouarg helpers for this.

The fix relies on features introduced in commit 52267790ef ("sock:
add MSG_ZEROCOPY"), so can be backported as is only to 4.14.

Tested with from `./in_netns.sh ./txring_overwrite` from
http://github.com/wdebruij/kerneltools/tests

Fixes: 69e3c75f4d ("net: TX_RING and packet mmap")
Reported-by: Anand H. Krishnan <anandhkrishnan@gmail.com>
Signed-off-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-11-23 11:08:03 -08:00
Cong Wang 7f600f14df net: remove unused skb_send_sock()
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-11-16 19:32:33 -08:00
Michał Mirosław 0c4b2d3705 net: remove VLAN_TAG_PRESENT
Replace VLAN_TAG_PRESENT with single bit flag and free up
VLAN.CFI overload. Now VLAN.CFI is visible in networking stack
and can be passed around intact.

Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-11-16 19:25:29 -08:00
Michał Mirosław 5109f9fd6a net/skbuff: add macros for VLAN_PRESENT bit
Wrap VLAN_PRESENT bit using macro like PKT_TYPE_* and CLONED_*,
as used by BPF code.

Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-11-16 19:25:28 -08:00
Yangtao Li 5e1abdc3fe net: skbuff.h: remove unnecessary unlikely()
WARN_ON() already contains an unlikely(), so it's not necessary to use
unlikely.

Signed-off-by: Yangtao Li <tiny.windzz@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-11-06 11:21:49 -08:00
Gustavo A. R. Silva 82385b0d2d net: skbuff.h: Mark expected switch fall-throughs
In preparation to enabling -Wimplicit-fallthrough, mark switch cases
where we are expecting to fall through.

Acked-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-17 22:31:30 -07:00
Paolo Abeni cc16567e5a net: drop unused skb_append_datato_frags()
This helper is unused since commit 988cf74deb ("inet:
Stop generating UFO packets.")

Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-02 11:18:09 -07:00
David S. Miller 105bc1306e Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next
Daniel Borkmann says:

====================
pull-request: bpf-next 2018-09-25

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

The main changes are:

1) Allow for RX stack hardening by implementing the kernel's flow
   dissector in BPF. Idea was originally presented at netconf 2017 [0].
   Quote from merge commit:

     [...] Because of the rigorous checks of the BPF verifier, this
     provides significant security guarantees. In particular, the BPF
     flow dissector cannot get inside of an infinite loop, as with
     CVE-2013-4348, because BPF programs are guaranteed to terminate.
     It cannot read outside of packet bounds, because all memory accesses
     are checked. Also, with BPF the administrator can decide which
     protocols to support, reducing potential attack surface. Rarely
     encountered protocols can be excluded from dissection and the
     program can be updated without kernel recompile or reboot if a
     bug is discovered. [...]

   Also, a sample flow dissector has been implemented in BPF as part
   of this work, from Petar and Willem.

   [0] http://vger.kernel.org/netconf2017_files/rx_hardening_and_udp_gso.pdf

2) Add support for bpftool to list currently active attachment
   points of BPF networking programs providing a quick overview
   similar to bpftool's perf subcommand, from Yonghong.

3) Fix a verifier pruning instability bug where a union member
   from the register state was not cleared properly leading to
   branches not being pruned despite them being valid candidates,
   from Alexei.

4) Various smaller fast-path optimizations in XDP's map redirect
   code, from Jesper.

5) Enable to recognize BPF_MAP_TYPE_REUSEPORT_SOCKARRAY maps
   in bpftool, from Roman.

6) Remove a duplicate check in libbpf that probes for function
   storage, from Taeung.

7) Fix an issue in test_progs by avoid checking for errno since
   on success its value should not be checked, from Mauricio.

8) Fix unused variable warning in bpf_getsockopt() helper when
   CONFIG_INET is not configured, from Anders.

9) Fix a compilation failure in the BPF sample code's use of
   bpf_flow_keys, from Prashant.

10) Minor cleanups in BPF code, from Yue and Zhong.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-09-25 20:29:38 -07:00
Eric Dumazet d3edd06ea8 tcp: provide earliest departure time in skb->tstamp
Switch internal TCP skb->skb_mstamp to skb->skb_mstamp_ns,
from usec units to nsec units.

Do not clear skb->tstamp before entering IP stacks in TX,
so that qdisc or devices can implement pacing based on the
earliest departure time instead of socket sk->sk_pacing_rate

Packets are fed with tcp_wstamp_ns, and following patch
will update tcp_wstamp_ns when both TCP and sch_fq switch to
the earliest departure time mechanism.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-09-21 19:37:59 -07:00
Willem de Bruijn 2dfd184abd flow_dissector: fix build failure without CONFIG_NET
If boolean CONFIG_BPF_SYSCALL is enabled, kernel/bpf/syscall.c will
call flow_dissector functions from net/core/flow_dissector.c.

This causes this build failure if CONFIG_NET is disabled:

    kernel/bpf/syscall.o: In function `__x64_sys_bpf':
    syscall.c:(.text+0x3278): undefined reference to
    `skb_flow_dissector_bpf_prog_attach'
    syscall.c:(.text+0x3310): undefined reference to
    `skb_flow_dissector_bpf_prog_detach'
    kernel/bpf/syscall.o:(.rodata+0x3f0): undefined reference to
    `flow_dissector_prog_ops'
    kernel/bpf/verifier.o:(.rodata+0x250): undefined reference to
    `flow_dissector_verifier_ops'

Analogous to other optional BPF program types in syscall.c, add stubs
if the relevant functions are not compiled and move the BPF_PROG_TYPE
definition in the #ifdef CONFIG_NET block.

Fixes: d58e468b11 ("flow_dissector: implements flow dissector BPF hook")
Reported-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Willem de Bruijn <willemb@google.com>
Acked-by: Randy Dunlap <rdunlap@infradead.org> # build-tested
Acked-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-09-19 23:46:44 +02:00
Petar Penkov d58e468b11 flow_dissector: implements flow dissector BPF hook
Adds a hook for programs of type BPF_PROG_TYPE_FLOW_DISSECTOR and
attach type BPF_FLOW_DISSECTOR that is executed in the flow dissector
path. The BPF program is per-network namespace.

Signed-off-by: Petar Penkov <ppenkov@google.com>
Signed-off-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-09-14 12:04:33 -07:00
David S. Miller 992cba7e27 net: Add and use skb_list_del_init().
It documents what is happening, and eliminates the spurious list
pointer poisoning.

In the long term, in order to get proper list head debugging, we
might want to use the list poison value as the indicator that
an SKB is a singleton and not on a list.

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-09-10 10:06:54 -07:00
David S. Miller a8305bff68 net: Add and use skb_mark_not_on_list().
An SKB is not on a list if skb->next is NULL.

Codify this convention into a helper function and use it
where we are dequeueing an SKB and need to mark it as such.

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-09-10 10:06:54 -07:00
David S. Miller 8b69bd7d8a ppp: Remove direct skb_queue_head list pointer access.
Add a helper, __skb_peek(), and use it in ppp_mp_reconstruct().

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-09-10 10:06:53 -07:00
David S. Miller c1617fb4c5 Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next
Daniel Borkmann says:

====================
pull-request: bpf-next 2018-08-13

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

The main changes are:

1) Add driver XDP support for veth. This can be used in conjunction with
   redirect of another XDP program e.g. sitting on NIC so the xdp_frame
   can be forwarded to the peer veth directly without modification,
   from Toshiaki.

2) Add a new BPF map type REUSEPORT_SOCKARRAY and prog type SK_REUSEPORT
   in order to provide more control and visibility on where a SO_REUSEPORT
   sk should be located, and the latter enables to directly select a sk
   from the bpf map. This also enables map-in-map for application migration
   use cases, from Martin.

3) Add a new BPF helper bpf_skb_ancestor_cgroup_id() that returns the id
   of cgroup v2 that is the ancestor of the cgroup associated with the
   skb at the ancestor_level, from Andrey.

4) Implement BPF fs map pretty-print support based on BTF data for regular
   hash table and LRU map, from Yonghong.

5) Decouple the ability to attach BTF for a map from the key and value
   pretty-printer in BPF fs, and enable further support of BTF for maps for
   percpu and LPM trie, from Daniel.

6) Implement a better BPF sample of using XDP's CPU redirect feature for
   load balancing SKB processing to remote CPU. The sample implements the
   same XDP load balancing as Suricata does which is symmetric hash based
   on IP and L4 protocol, from Jesper.

7) Revert adding NULL pointer check with WARN_ON_ONCE() in __xdp_return()'s
   critical path as it is ensured that the allocator is present, from Björn.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-08-13 10:07:23 -07:00
Toshiaki Makita b0768a8658 net: Export skb_headers_offset_update
This is needed for veth XDP which does skb_copy_expand()-like operation.

v2:
- Drop skb_copy_header part because it has already been exported now.

Signed-off-by: Toshiaki Makita <makita.toshiaki@lab.ntt.co.jp>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-08-10 16:12:20 +02:00
YueHaibing 15693fd37f net: skbuff.h: fix using plain integer as NULL warning
Fixes the following sparse warning:
./include/linux/skbuff.h:2365:58: warning: Using plain integer as NULL pointer

Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-08-09 14:10:01 -07:00
Peter Oskolkov fa0f527358 ip: use rb trees for IP frag queue.
Similar to TCP OOO RX queue, it makes sense to use rb trees to store
IP fragments, so that OOO fragments are inserted faster.

Tested:

- a follow-up patch contains a rather comprehensive ip defrag
  self-test (functional)
- ran neper `udp_stream -c -H <host> -F 100 -l 300 -T 20`:
    netstat --statistics
    Ip:
        282078937 total packets received
        0 forwarded
        0 incoming packets discarded
        946760 incoming packets delivered
        18743456 requests sent out
        101 fragments dropped after timeout
        282077129 reassemblies required
        944952 packets reassembled ok
        262734239 packet reassembles failed
   (The numbers/stats above are somewhat better re:
    reassemblies vs a kernel without this patchset. More
    comprehensive performance testing TBD).

Reported-by: Jann Horn <jannh@google.com>
Reported-by: Juha-Matti Tilli <juha-matti.tilli@iki.fi>
Suggested-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Peter Oskolkov <posk@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Florian Westphal <fw@strlen.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-08-05 17:16:46 -07:00
Peter Oskolkov 385114dec8 net: modify skb_rbtree_purge to return the truesize of all purged skbs.
Tested: see the next patch is the series.

Suggested-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Peter Oskolkov <posk@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Florian Westphal <fw@strlen.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-08-05 17:16:46 -07:00
David S. Miller c4c5551df1 Merge ra.kernel.org:/pub/scm/linux/kernel/git/torvalds/linux
All conflicts were trivial overlapping changes, so reasonably
easy to resolve.

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-20 21:17:12 -07:00
Stefano Brivio a48d189ef5 net: Move skb decrypted field, avoid explicity copy
Commit 784abe24c9 ("net: Add decrypted field to skb")
introduced a 'decrypted' field that is explicitly copied on skb
copy and clone.

Move it between headers_start[0] and headers_end[0], so that we
don't need to copy it explicitly as it's copied by the memcpy()
in __copy_skb_header().

While at it, drop the assignment in __skb_clone(), it was
already redundant.

This doesn't change the size of sk_buff or cacheline boundaries.

The 15-bits hole before tc_index becomes a 14-bits hole, and
will be again a 15-bits hole when this change is merged with
commit 8b7008620b ("net: Don't copy pfmemalloc flag in
__copy_skb_header()").

v2: as reported by kbuild test robot (oops, I forgot to build
    with CONFIG_TLS_DEVICE it seems), we can't use
    CHECK_SKB_FIELD() on a bit-field member. Just drop the
    check for the moment being, perhaps we could think of some
    magic to also check bit-field members one day.

Fixes: 784abe24c9 ("net: Add decrypted field to skb")
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-18 13:42:08 -07:00
Boris Pismenny 784abe24c9 net: Add decrypted field to skb
The decrypted bit is propogated to cloned/copied skbs.
This will be used later by the inline crypto receive side offload
of tls.

Signed-off-by: Boris Pismenny <borisp@mellanox.com>
Signed-off-by: Ilya Lesokhin <ilyal@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-16 00:12:09 -07:00
Stefano Brivio 8b7008620b net: Don't copy pfmemalloc flag in __copy_skb_header()
The pfmemalloc flag indicates that the skb was allocated from
the PFMEMALLOC reserves, and the flag is currently copied on skb
copy and clone.

However, an skb copied from an skb flagged with pfmemalloc
wasn't necessarily allocated from PFMEMALLOC reserves, and on
the other hand an skb allocated that way might be copied from an
skb that wasn't.

So we should not copy the flag on skb copy, and rather decide
whether to allow an skb to be associated with sockets unrelated
to page reclaim depending only on how it was allocated.

Move the pfmemalloc flag before headers_start[0] using an
existing 1-bit hole, so that __copy_skb_header() doesn't copy
it.

When cloning, we'll now take care of this flag explicitly,
contravening to the warning comment of __skb_clone().

While at it, restore the newline usage introduced by commit
b193722731 ("net: reorganize sk_buff for faster
__copy_skb_header()") to visually separate bytes used in
bitfields after headers_start[0], that was gone after commit
a9e419dc7b ("netfilter: merge ctinfo into nfct pointer storage
area"), and describe the pfmemalloc flag in the kernel-doc
structure comment.

This doesn't change the size of sk_buff or cacheline boundaries,
but consolidates the 15 bits hole before tc_index into a 2 bytes
hole before csum, that could now be filled more easily.

Reported-by: Patrick Talbert <ptalbert@redhat.com>
Fixes: c93bdd0e03 ("netvm: allow skb allocation to use PFMEMALLOC reserves")
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-12 15:15:16 -07:00
David S. Miller 5cd3da4ba2 Merge ra.kernel.org:/pub/scm/linux/kernel/git/davem/net
Simple overlapping changes in stmmac driver.

Adjust skb_gro_flush_final_remcsum function signature to make GRO list
changes in net-next, as per Stephen Rothwell's example merge
resolution.

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-03 10:29:26 +09:00
Linus Torvalds a11e1d432b Revert changes to convert to ->poll_mask() and aio IOCB_CMD_POLL
The poll() changes were not well thought out, and completely
unexplained.  They also caused a huge performance regression, because
"->poll()" was no longer a trivial file operation that just called down
to the underlying file operations, but instead did at least two indirect
calls.

Indirect calls are sadly slow now with the Spectre mitigation, but the
performance problem could at least be largely mitigated by changing the
"->get_poll_head()" operation to just have a per-file-descriptor pointer
to the poll head instead.  That gets rid of one of the new indirections.

But that doesn't fix the new complexity that is completely unwarranted
for the regular case.  The (undocumented) reason for the poll() changes
was some alleged AIO poll race fixing, but we don't make the common case
slower and more complex for some uncommon special case, so this all
really needs way more explanations and most likely a fundamental
redesign.

[ This revert is a revert of about 30 different commits, not reverted
  individually because that would just be unnecessarily messy  - Linus ]

Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-06-28 10:40:47 -07:00
David Miller d4546c2509 net: Convert GRO SKB handling to list_head.
Manage pending per-NAPI GRO packets via list_head.

Return an SKB pointer from the GRO receive handlers.  When GRO receive
handlers return non-NULL, it means that this SKB needs to be completed
at this time and removed from the NAPI queue.

Several operations are greatly simplified by this transformation,
especially timing out the oldest SKB in the list when gro_count
exceeds MAX_GRO_SKBS, and napi_gro_flush() which walks the queue
in reverse order.

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-06-26 11:33:04 +09:00
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
Randy Dunlap 1f4c741321 net: skbuff.h: drop unneeded <linux/slab.h>
<linux/skbuff.h> does not use nor need <linux/slab.h>, so drop this
header file from skbuff.h.

<linux/skbuff.h> is currently #included in around 1200 C source and
header files, making it the 31st most-used header file.

Build tested [allmodconfig] on 20 arch-es.

Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-06-04 17:02:06 -04:00
Christoph Hellwig db5051ead6 net: convert datagram_poll users tp ->poll_mask
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-26 09:16:44 +02:00
Paolo Abeni 72a338bcc6 net: core: rework basic flow dissection helper
When the core networking needs to detect the transport offset in a given
packet and parse it explicitly, a full-blown flow_keys struct is used for
storage.
This patch introduces a smaller keys store, rework the basic flow dissect
helper to use it, and apply this new helper where possible - namely in
skb_probe_transport_header(). The used flow dissector data structures
are renamed to match more closely the new role.

The above gives ~50% performance improvement in micro benchmarking around
skb_probe_transport_header() and ~30% around eth_get_headlen(), mostly due
to the smaller memset. Small, but measurable improvement is measured also
in macro benchmarking.

v1 -> v2: use the new helper in eth_get_headlen() and skb_get_poff(),
  as per DaveM suggestion

Suggested-by: David Miller <davem@davemloft.net>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-05-08 00:02:36 -04:00
Ilya Lesokhin 08303c1895 net: Rename and export copy_skb_header
copy_skb_header is renamed to skb_copy_header and
exported. Exposing this function give more flexibility
in copying SKBs.
skb_copy and skb_copy_expand do not give enough control
over which parts are copied.

Signed-off-by: Ilya Lesokhin <ilyal@mellanox.com>
Signed-off-by: Boris Pismenny <borisp@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-05-01 09:42:46 -04:00
Willem de Bruijn ee80d1ebe5 udp: add udp gso
Implement generic segmentation offload support for udp datagrams. A
follow-up patch adds support to the protocol stack to generate such
packets.

UDP GSO is not UFO. UFO fragments a single large datagram. GSO splits
a large payload into a number of discrete UDP datagrams.

The implementation adds a GSO type SKB_UDP_GSO_L4 to differentiate it
from UFO (SKB_UDP_GSO).

IPPROTO_UDPLITE is excluded, as that protocol has no gso handler
registered.

[ Export __udp_gso_segment for ipv6. -DaveM ]

Signed-off-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-04-26 15:07:42 -04:00
Eric Dumazet 88078d98d1 net: pskb_trim_rcsum() and CHECKSUM_COMPLETE are friends
After working on IP defragmentation lately, I found that some large
packets defeat CHECKSUM_COMPLETE optimization because of NIC adding
zero paddings on the last (small) fragment.

While removing the padding with pskb_trim_rcsum(), we set skb->ip_summed
to CHECKSUM_NONE, forcing a full csum validation, even if all prior
fragments had CHECKSUM_COMPLETE set.

We can instead compute the checksum of the part we are trimming,
usually smaller than the part we keep.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-04-19 13:44:11 -04:00
Eric Dumazet bf66337140 inet: frags: get rid of ipfrag_skb_cb/FRAG_CB
ip_defrag uses skb->cb[] to store the fragment offset, and unfortunately
this integer is currently in a different cache line than skb->next,
meaning that we use two cache lines per skb when finding the insertion point.

By aliasing skb->ip_defrag_offset and skb->dev, we pack all the fields
in a single cache line and save precious memory bandwidth.

Note that after the fast path added by Changli Gao in commit
d6bebca92c ("fragment: add fast path for in-order fragments")
this change wont help the fast path, since we still need
to access prev->len (2nd cache line), but will show great
benefits when slow path is entered, since we perform
a linear scan of a potentially long list.

Also, note that this potential long list is an attack vector,
we might consider also using an rb-tree there eventually.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-03-31 23:25:40 -04:00
David S. Miller 03fe2debbb Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Fun set of conflict resolutions here...

For the mac80211 stuff, these were fortunately just parallel
adds.  Trivially resolved.

In drivers/net/phy/phy.c we had a bug fix in 'net' that moved the
function phy_disable_interrupts() earlier in the file, whilst in
'net-next' the phy_error() call from this function was removed.

In net/ipv4/xfrm4_policy.c, David Ahern's changes to remove the
'rt_table_id' member of rtable collided with a bug fix in 'net' that
added a new struct member "rt_mtu_locked" which needs to be copied
over here.

The mlxsw driver conflict consisted of net-next separating
the span code and definitions into separate files, whilst
a 'net' bug fix made some changes to that moved code.

The mlx5 infiniband conflict resolution was quite non-trivial,
the RDMA tree's merge commit was used as a guide here, and
here are their notes:

====================

    Due to bug fixes found by the syzkaller bot and taken into the for-rc
    branch after development for the 4.17 merge window had already started
    being taken into the for-next branch, there were fairly non-trivial
    merge issues that would need to be resolved between the for-rc branch
    and the for-next branch.  This merge resolves those conflicts and
    provides a unified base upon which ongoing development for 4.17 can
    be based.

    Conflicts:
            drivers/infiniband/hw/mlx5/main.c - Commit 42cea83f95
            (IB/mlx5: Fix cleanup order on unload) added to for-rc and
            commit b5ca15ad7e (IB/mlx5: Add proper representors support)
            add as part of the devel cycle both needed to modify the
            init/de-init functions used by mlx5.  To support the new
            representors, the new functions added by the cleanup patch
            needed to be made non-static, and the init/de-init list
            added by the representors patch needed to be modified to
            match the init/de-init list changes made by the cleanup
            patch.
    Updates:
            drivers/infiniband/hw/mlx5/mlx5_ib.h - Update function
            prototypes added by representors patch to reflect new function
            names as changed by cleanup patch
            drivers/infiniband/hw/mlx5/ib_rep.c - Update init/de-init
            stage list to match new order from cleanup patch
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-03-23 11:31:58 -04:00
David S. Miller cfda06d736 Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf
Daniel Borkmann says:

====================
pull-request: bpf 2018-03-08

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

The main changes are:

1) Fix various BPF helpers which adjust the skb and its GSO information
   with regards to SCTP GSO. The latter is a special case where gso_size
   is of value GSO_BY_FRAGS, so mangling that will end up corrupting
   the skb, thus bail out when seeing SCTP GSO packets, from Daniel(s).

2) Fix a compilation error in bpftool where BPF_FS_MAGIC is not defined
   due to too old kernel headers in the system, from Jiri.

3) Increase the number of x64 JIT passes in order to allow larger images
   to converge instead of punting them to interpreter or having them
   rejected when the interpreter is not built into the kernel, from Daniel.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-03-07 20:27:51 -05:00
David S. Miller 0f3e9c97eb Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
All of the conflicts were cases of overlapping changes.

In net/core/devlink.c, we have to make care that the
resouce size_params have become a struct member rather
than a pointer to such an object.

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-03-06 01:20:46 -05:00
Daniel Axtens a4a77718ee net: make skb_gso_*_seglen functions private
They're very hard to use properly as they do not consider the
GSO_BY_FRAGS case. Code should use skb_gso_validate_network_len
and skb_gso_validate_mac_len as they do consider this case.

Make the seglen functions static, which stops people using them
outside of skbuff.c

Signed-off-by: Daniel Axtens <dja@axtens.net>
Reviewed-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-03-04 17:49:17 -05:00
Daniel Axtens 779b7931b2 net: rename skb_gso_validate_mtu -> skb_gso_validate_network_len
If you take a GSO skb, and split it into packets, will the network
length (L3 headers + L4 headers + payload) of those packets be small
enough to fit within a given MTU?

skb_gso_validate_mtu gives you the answer to that question. However,
we recently added to add a way to validate the MAC length of a split GSO
skb (L2+L3+L4+payload), and the names get confusing, so rename
skb_gso_validate_mtu to skb_gso_validate_network_len

Signed-off-by: Daniel Axtens <dja@axtens.net>
Reviewed-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-03-04 17:49:17 -05:00
Daniel Axtens d02f51cbcf bpf: fix bpf_skb_adjust_net/bpf_skb_proto_xlat to deal with gso sctp skbs
SCTP GSO skbs have a gso_size of GSO_BY_FRAGS, so any sort of
unconditionally mangling of that will result in nonsense value
and would corrupt the skb later on.

Therefore, i) add two helpers skb_increase_gso_size() and
skb_decrease_gso_size() that would throw a one time warning and
bail out for such skbs and ii) refuse and return early with an
error in those BPF helpers that are affected. We do need to bail
out as early as possible from there before any changes on the
skb have been performed.

Fixes: 6578171a7f ("bpf: add bpf_skb_change_proto helper")
Co-authored-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Daniel Axtens <dja@axtens.net>
Cc: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-03-03 13:01:11 -08:00
David S. Miller f5c0c6f429 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2018-02-19 18:46:11 -05:00
Sowmini Varadhan 6f89dbce8e skbuff: export mm_[un]account_pinned_pages for other modules
RDS would like to use the helper functions for managing pinned pages
added by Commit a91dbff551 ("sock: ulimit on MSG_ZEROCOPY pages")

Signed-off-by: Sowmini Varadhan <sowmini.varadhan@oracle.com>
Acked-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-02-16 16:04:16 -05:00
David S. Miller da27988766 skbuff: Fix comment mis-spelling.
'peform' --> 'perform'

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-02-16 15:52:42 -05:00
Daniel Axtens 2b16f04872 net: create skb_gso_validate_mac_len()
If you take a GSO skb, and split it into packets, will the MAC
length (L2 + L3 + L4 headers + payload) of those packets be small
enough to fit within a given length?

Move skb_gso_mac_seglen() to skbuff.h with other related functions
like skb_gso_network_seglen() so we can use it, and then create
skb_gso_validate_mac_len to do the full calculation.

Signed-off-by: Daniel Axtens <dja@axtens.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-02-01 09:36:03 -05:00
Linus Torvalds b2fe5fa686 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next
Pull networking updates from David Miller:

 1) Significantly shrink the core networking routing structures. Result
    of http://vger.kernel.org/~davem/seoul2017_netdev_keynote.pdf

 2) Add netdevsim driver for testing various offloads, from Jakub
    Kicinski.

 3) Support cross-chip FDB operations in DSA, from Vivien Didelot.

 4) Add a 2nd listener hash table for TCP, similar to what was done for
    UDP. From Martin KaFai Lau.

 5) Add eBPF based queue selection to tun, from Jason Wang.

 6) Lockless qdisc support, from John Fastabend.

 7) SCTP stream interleave support, from Xin Long.

 8) Smoother TCP receive autotuning, from Eric Dumazet.

 9) Lots of erspan tunneling enhancements, from William Tu.

10) Add true function call support to BPF, from Alexei Starovoitov.

11) Add explicit support for GRO HW offloading, from Michael Chan.

12) Support extack generation in more netlink subsystems. From Alexander
    Aring, Quentin Monnet, and Jakub Kicinski.

13) Add 1000BaseX, flow control, and EEE support to mvneta driver. From
    Russell King.

14) Add flow table abstraction to netfilter, from Pablo Neira Ayuso.

15) Many improvements and simplifications to the NFP driver bpf JIT,
    from Jakub Kicinski.

16) Support for ipv6 non-equal cost multipath routing, from Ido
    Schimmel.

17) Add resource abstration to devlink, from Arkadi Sharshevsky.

18) Packet scheduler classifier shared filter block support, from Jiri
    Pirko.

19) Avoid locking in act_csum, from Davide Caratti.

20) devinet_ioctl() simplifications from Al viro.

21) More TCP bpf improvements from Lawrence Brakmo.

22) Add support for onlink ipv6 route flag, similar to ipv4, from David
    Ahern.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1925 commits)
  tls: Add support for encryption using async offload accelerator
  ip6mr: fix stale iterator
  net/sched: kconfig: Remove blank help texts
  openvswitch: meter: Use 64-bit arithmetic instead of 32-bit
  tcp_nv: fix potential integer overflow in tcpnv_acked
  r8169: fix RTL8168EP take too long to complete driver initialization.
  qmi_wwan: Add support for Quectel EP06
  rtnetlink: enable IFLA_IF_NETNSID for RTM_NEWLINK
  ipmr: Fix ptrdiff_t print formatting
  ibmvnic: Wait for device response when changing MAC
  qlcnic: fix deadlock bug
  tcp: release sk_frag.page in tcp_disconnect
  ipv4: Get the address of interface correctly.
  net_sched: gen_estimator: fix lockdep splat
  net: macb: Handle HRESP error
  net/mlx5e: IPoIB, Fix copy-paste bug in flow steering refactoring
  ipv6: addrconf: break critical section in addrconf_verify_rtnl()
  ipv6: change route cache aging logic
  i40e/i40evf: Update DESC_NEEDED value to reflect larger value
  bnxt_en: cleanup DIM work on device shutdown
  ...
2018-01-31 14:31:10 -08:00
Linus Torvalds 168fe32a07 Merge branch 'misc.poll' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull poll annotations from Al Viro:
 "This introduces a __bitwise type for POLL### bitmap, and propagates
  the annotations through the tree. Most of that stuff is as simple as
  'make ->poll() instances return __poll_t and do the same to local
  variables used to hold the future return value'.

  Some of the obvious brainos found in process are fixed (e.g. POLLIN
  misspelled as POLL_IN). At that point the amount of sparse warnings is
  low and most of them are for genuine bugs - e.g. ->poll() instance
  deciding to return -EINVAL instead of a bitmap. I hadn't touched those
  in this series - it's large enough as it is.

  Another problem it has caught was eventpoll() ABI mess; select.c and
  eventpoll.c assumed that corresponding POLL### and EPOLL### were
  equal. That's true for some, but not all of them - EPOLL### are
  arch-independent, but POLL### are not.

  The last commit in this series separates userland POLL### values from
  the (now arch-independent) kernel-side ones, converting between them
  in the few places where they are copied to/from userland. AFAICS, this
  is the least disruptive fix preserving poll(2) ABI and making epoll()
  work on all architectures.

  As it is, it's simply broken on sparc - try to give it EPOLLWRNORM and
  it will trigger only on what would've triggered EPOLLWRBAND on other
  architectures. EPOLLWRBAND and EPOLLRDHUP, OTOH, are never triggered
  at all on sparc. With this patch they should work consistently on all
  architectures"

* 'misc.poll' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (37 commits)
  make kernel-side POLL... arch-independent
  eventpoll: no need to mask the result of epi_item_poll() again
  eventpoll: constify struct epoll_event pointers
  debugging printk in sg_poll() uses %x to print POLL... bitmap
  annotate poll(2) guts
  9p: untangle ->poll() mess
  ->si_band gets POLL... bitmap stored into a user-visible long field
  ring_buffer_poll_wait() return value used as return value of ->poll()
  the rest of drivers/*: annotate ->poll() instances
  media: annotate ->poll() instances
  fs: annotate ->poll() instances
  ipc, kernel, mm: annotate ->poll() instances
  net: annotate ->poll() instances
  apparmor: annotate ->poll() instances
  tomoyo: annotate ->poll() instances
  sound: annotate ->poll() instances
  acpi: annotate ->poll() instances
  crypto: annotate ->poll() instances
  block: annotate ->poll() instances
  x86: annotate ->poll() instances
  ...
2018-01-30 17:58:07 -08:00
Simon Horman 62b32379fd flow_dissector: dissect tunnel info outside __skb_flow_dissect()
Move dissection of tunnel info to outside of the main flow dissection
function, __skb_flow_dissect(). The sole user of this feature, the flower
classifier, is updated to call tunnel info dissection directly, using
skb_flow_dissect_tunnel_info().

This results in a slightly less complex implementation of
__skb_flow_dissect(), in particular removing logic from that call path
which is not used by the majority of users. The expense of this is borne by
the flower classifier which now has to make an extra call for tunnel info
dissection.

This patch should not result in any behavioural change.

Signed-off-by: Simon Horman <simon.horman@netronome.com>
Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-05 12:09:18 -05:00
Geert Uytterhoeven f8821f96ae skbuff: Grammar s/are can/can/, s/change/changes/
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-30 09:15:53 -05:00
Al Viro ade994f4f6 net: annotate ->poll() instances
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2017-11-27 16:20:04 -05:00
Willem de Bruijn 0c19f846d5 net: accept UFO datagrams from tuntap and packet
Tuntap and similar devices can inject GSO packets. Accept type
VIRTIO_NET_HDR_GSO_UDP, even though not generating UFO natively.

Processes are expected to use feature negotiation such as TUNSETOFFLOAD
to detect supported offload types and refrain from injecting other
packets. This process breaks down with live migration: guest kernels
do not renegotiate flags, so destination hosts need to expose all
features that the source host does.

Partially revert the UFO removal from 182e0b6b5846~1..d9d30adf5677.
This patch introduces nearly(*) no new code to simplify verification.
It brings back verbatim tuntap UFO negotiation, VIRTIO_NET_HDR_GSO_UDP
insertion and software UFO segmentation.

It does not reinstate protocol stack support, hardware offload
(NETIF_F_UFO), SKB_GSO_UDP tunneling in SKB_GSO_SOFTWARE or reception
of VIRTIO_NET_HDR_GSO_UDP packets in tuntap.

To support SKB_GSO_UDP reappearing in the stack, also reinstate
logic in act_csum and openvswitch. Achieve equivalence with v4.13 HEAD
by squashing in commit 939912216f ("net: skb_needs_check() removes
CHECKSUM_UNNECESSARY check for tx.") and reverting commit 8d63bee643
("net: avoid skb_warn_bad_offload false positives on UFO").

(*) To avoid having to bring back skb_shinfo(skb)->ip6_frag_id,
ipv6_proxy_select_ident is changed to return a __be32 and this is
assigned directly to the frag_hdr. Also, SKB_GSO_UDP is inserted
at the end of the enum to minimize code churn.

Tested
  Booted a v4.13 guest kernel with QEMU. On a host kernel before this
  patch `ethtool -k eth0` shows UFO disabled. After the patch, it is
  enabled, same as on a v4.13 host kernel.

  A UFO packet sent from the guest appears on the tap device:
    host:
      nc -l -p -u 8000 &
      tcpdump -n -i tap0

    guest:
      dd if=/dev/zero of=payload.txt bs=1 count=2000
      nc -u 192.16.1.1 8000 < payload.txt

  Direct tap to tap transmission of VIRTIO_NET_HDR_GSO_UDP succeeds,
  packets arriving fragmented:

    ./with_tap_pair.sh ./tap_send_ufo tap0 tap1
    (from https://github.com/wdebruij/kerneltools/tree/master/tests)

Changes
  v1 -> v2
    - simplified set_offload change (review comment)
    - documented test procedure

Link: http://lkml.kernel.org/r/<CAF=yD-LuUeDuL9YWPJD9ykOZ0QCjNeznPDr6whqZ9NGMNF12Mw@mail.gmail.com>
Fixes: fb652fdfe8 ("macvlan/macvtap: Remove NETIF_F_UFO advertisement.")
Reported-by: Michal Kubecek <mkubecek@suse.cz>
Signed-off-by: Willem de Bruijn <willemb@google.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-24 01:37:35 +09:00
Linus Torvalds 7c225c69f8 Merge branch 'akpm' (patches from Andrew)
Merge updates from Andrew Morton:

 - a few misc bits

 - ocfs2 updates

 - almost all of MM

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (131 commits)
  memory hotplug: fix comments when adding section
  mm: make alloc_node_mem_map a void call if we don't have CONFIG_FLAT_NODE_MEM_MAP
  mm: simplify nodemask printing
  mm,oom_reaper: remove pointless kthread_run() error check
  mm/page_ext.c: check if page_ext is not prepared
  writeback: remove unused function parameter
  mm: do not rely on preempt_count in print_vma_addr
  mm, sparse: do not swamp log with huge vmemmap allocation failures
  mm/hmm: remove redundant variable align_end
  mm/list_lru.c: mark expected switch fall-through
  mm/shmem.c: mark expected switch fall-through
  mm/page_alloc.c: broken deferred calculation
  mm: don't warn about allocations which stall for too long
  fs: fuse: account fuse_inode slab memory as reclaimable
  mm, page_alloc: fix potential false positive in __zone_watermark_ok
  mm: mlock: remove lru_add_drain_all()
  mm, sysctl: make NUMA stats configurable
  shmem: convert shmem_init_inodecache() to void
  Unify migrate_pages and move_pages access checks
  mm, pagevec: rename pagevec drained field
  ...
2017-11-15 19:42:40 -08:00
Mel Gorman 453f85d43f mm: remove __GFP_COLD
As the page free path makes no distinction between cache hot and cold
pages, there is no real useful ordering of pages in the free list that
allocation requests can take advantage of.  Juding from the users of
__GFP_COLD, it is likely that a number of them are the result of copying
other sites instead of actually measuring the impact.  Remove the
__GFP_COLD parameter which simplifies a number of paths in the page
allocator.

This is potentially controversial but bear in mind that the size of the
per-cpu pagelists versus modern cache sizes means that the whole per-cpu
list can often fit in the L3 cache.  Hence, there is only a potential
benefit for microbenchmarks that alloc/free pages in a tight loop.  It's
even worse when THP is taken into account which has little or no chance
of getting a cache-hot page as the per-cpu list is bypassed and the
zeroing of multiple pages will thrash the cache anyway.

The truncate microbenchmarks are not shown as this patch affects the
allocation path and not the free path.  A page fault microbenchmark was
tested but it showed no sigificant difference which is not surprising
given that the __GFP_COLD branches are a miniscule percentage of the
fault path.

Link: http://lkml.kernel.org/r/20171018075952.10627-9-mgorman@techsingularity.net
Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-11-15 18:21:06 -08:00
Levin, Alexander (Sasha Levin) 4950276672 kmemcheck: remove annotations
Patch series "kmemcheck: kill kmemcheck", v2.

As discussed at LSF/MM, kill kmemcheck.

KASan is a replacement that is able to work without the limitation of
kmemcheck (single CPU, slow).  KASan is already upstream.

We are also not aware of any users of kmemcheck (or users who don't
consider KASan as a suitable replacement).

The only objection was that since KASAN wasn't supported by all GCC
versions provided by distros at that time we should hold off for 2
years, and try again.

Now that 2 years have passed, and all distros provide gcc that supports
KASAN, kill kmemcheck again for the very same reasons.

This patch (of 4):

Remove kmemcheck annotations, and calls to kmemcheck from the kernel.

[alexander.levin@verizon.com: correctly remove kmemcheck call from dma_map_sg_attrs]
  Link: http://lkml.kernel.org/r/20171012192151.26531-1-alexander.levin@verizon.com
Link: http://lkml.kernel.org/r/20171007030159.22241-2-alexander.levin@verizon.com
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Tim Hansen <devtimhansen@gmail.com>
Cc: Vegard Nossum <vegardno@ifi.uio.no>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-11-15 18:21:04 -08:00
Mat Martineau 39b1752110 net: Remove unused skb_shared_info member
ip6_frag_id was only used by UFO, which has been removed.
ipv6_proxy_select_ident() only existed to set ip6_frag_id and has no
in-tree callers.

Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-11 22:09:40 +09:00
David S. Miller 4dc6758d78 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Simple cases of overlapping changes in the packet scheduler.

Must easier to resolve this time.

Which probably means that I screwed it up somehow.

Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-10 10:00:18 +09:00
Ye Yin 2b5ec1a5f9 netfilter/ipvs: clear ipvs_property flag when SKB net namespace changed
When run ipvs in two different network namespace at the same host, and one
ipvs transport network traffic to the other network namespace ipvs.
'ipvs_property' flag will make the second ipvs take no effect. So we should
clear 'ipvs_property' when SKB network namespace changed.

Fixes: 621e84d6f3 ("dev: introduce skb_scrub_packet()")
Signed-off-by: Ye Yin <hustcat@gmail.com>
Signed-off-by: Wei Zhou <chouryzhou@gmail.com>
Signed-off-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Simon Horman <horms@verge.net.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-04 22:37:42 +09:00
Eric Dumazet 18a4c0eab2 net: add rb_to_skb() and other rb tree helpers
Geeralize private netem_rb_to_skb()

TCP rtx queue will soon be converted to rb-tree,
so we will need skb_rbtree_walk() helpers.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-07 00:28:53 +01:00
Eric Dumazet e2080072ed tcp: new list for sent but unacked skbs for RACK recovery
This patch adds a new queue (list) that tracks the sent but not yet
acked or SACKed skbs for a TCP connection. The list is chronologically
ordered by skb->skb_mstamp (the head is the oldest sent skb).

This list will be used to optimize TCP Rack recovery, which checks
an skb's timestamp to judge if it has been lost and needs to be
retransmitted. Since TCP write queue is ordered by sequence instead
of sent time, RACK has to scan over the write queue to catch all
eligible packets to detect lost retransmission, and iterates through
SACKed skbs repeatedly.

Special cares for rare events:
1. TCP repair fakes skb transmission so the send queue needs adjusted
2. SACK reneging would require re-inserting SACKed skbs into the
   send queue. For now I believe it's not worth the complexity to
   make RACK work perfectly on SACK reneging, so we do nothing here.
3. Fast Open: currently for non-TFO, send-queue correctly queues
   the pure SYN packet. For TFO which queues a pure SYN and
   then a data packet, send-queue only queues the data packet but
   not the pure SYN due to the structure of TFO code. This is okay
   because the SYN receiver would never respond with a SACK on a
   missing SYN (i.e. SYN is never fast-retransmitted by SACK/RACK).

In order to not grow sk_buff, we use an union for the new list and
_skb_refdst/destructor fields. This is a bit complicated because
we need to make sure _skb_refdst and destructor are properly zeroed
before skb is cloned/copied at transmit, and before being freed.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-05 21:24:47 -07:00
Yotam Gigi abf4bb6b63 skbuff: Add the offload_mr_fwd_mark field
Similarly to the offload_fwd_mark field, the offload_mr_fwd_mark field is
used to allow partial offloading of MFC multicast routes.

Switchdev drivers can offload MFC multicast routes to the hardware by
registering to the FIB notification chain. When one of the route output
interfaces is not offload-able, i.e. has different parent ID, the route
cannot be fully offloaded by the hardware. Examples to non-offload-able
devices are a management NIC, dummy device, pimreg device, etc.

Similar problem exists in the bridge module, as one bridge can hold
interfaces with different parent IDs. At the bridge, the problem is solved
by the offload_fwd_mark skb field.

Currently, when a route cannot go through full offload, the only solution
for a switchdev driver is not to offload it at all and let the packet go
through slow path.

Using the offload_mr_fwd_mark field, a driver can indicate that a packet
was already forwarded by hardware to all the devices with the same parent
ID as the input device. Further patches in this patch-set are going to
enhance ipmr to skip multicast forwarding to devices with the same parent
ID if a packets is marked with that field.

The reason why the already existing "offload_fwd_mark" bit cannot be used
is that a switchdev driver would want to make the distinction between a
packet that has already gone through L2 forwarding but did not go through
multicast forwarding, and a packet that has already gone through both L2
and multicast forwarding.

For example: when a packet is ingressing from a switchport enslaved to a
bridge, which is configured with multicast forwarding, the following
scenarios are possible:
 - The packet can be trapped to the CPU due to exception while multicast
   forwarding (for example, MTU error). In that case, it had already gone
   through L2 forwarding in the hardware, thus A switchdev driver would
   want to set the skb->offload_fwd_mark and not the
   skb->offload_mr_fwd_mark.
 - The packet can also be trapped due to a pimreg/dummy device used as one
   of the output interfaces. In that case, it can go through both L2 and
   (partial) multicast forwarding inside the hardware, thus a switchdev
   driver would want to set both the skb->offload_fwd_mark and
   skb->offload_mr_fwd_mark.

Signed-off-by: Yotam Gigi <yotamg@mellanox.com>
Reviewed-by: Ido Schimmel <idosch@mellaox.com>
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-03 10:06:30 -07:00
Daniel Borkmann de8f3a83b0 bpf: add meta pointer for direct access
This work enables generic transfer of metadata from XDP into skb. The
basic idea is that we can make use of the fact that the resulting skb
must be linear and already comes with a larger headroom for supporting
bpf_xdp_adjust_head(), which mangles xdp->data. Here, we base our work
on a similar principle and introduce a small helper bpf_xdp_adjust_meta()
for adjusting a new pointer called xdp->data_meta. Thus, the packet has
a flexible and programmable room for meta data, followed by the actual
packet data. struct xdp_buff is therefore laid out that we first point
to data_hard_start, then data_meta directly prepended to data followed
by data_end marking the end of packet. bpf_xdp_adjust_head() takes into
account whether we have meta data already prepended and if so, memmove()s
this along with the given offset provided there's enough room.

xdp->data_meta is optional and programs are not required to use it. The
rationale is that when we process the packet in XDP (e.g. as DoS filter),
we can push further meta data along with it for the XDP_PASS case, and
give the guarantee that a clsact ingress BPF program on the same device
can pick this up for further post-processing. Since we work with skb
there, we can also set skb->mark, skb->priority or other skb meta data
out of BPF, thus having this scratch space generic and programmable
allows for more flexibility than defining a direct 1:1 transfer of
potentially new XDP members into skb (it's also more efficient as we
don't need to initialize/handle each of such new members). The facility
also works together with GRO aggregation. The scratch space at the head
of the packet can be multiple of 4 byte up to 32 byte large. Drivers not
yet supporting xdp->data_meta can simply be set up with xdp->data_meta
as xdp->data + 1 as bpf_xdp_adjust_meta() will detect this and bail out,
such that the subsequent match against xdp->data for later access is
guaranteed to fail.

The verifier treats xdp->data_meta/xdp->data the same way as we treat
xdp->data/xdp->data_end pointer comparisons. The requirement for doing
the compare against xdp->data is that it hasn't been modified from it's
original address we got from ctx access. It may have a range marking
already from prior successful xdp->data/xdp->data_end pointer comparisons
though.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-09-26 13:36:44 -07:00