Add skb_frag_off(), skb_frag_off_add(), skb_frag_off_set(),
and skb_frag_off_copy() accessors for page_offset.
Signed-off-by: NJonathan Lemon <jonathan.lemon@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

There are a lot of users of frag->page_offset, so use a union
to avoid converting those users today.
Signed-off-by: NMatthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Improved compatibility with bvec
Signed-off-by: NMatthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

One step closer to turning the skb_frag_t into a bio_vec.
Signed-off-by: NMatthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Match the layout of bio_vec.
Signed-off-by: NMatthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

To increase commonality between block and net, we are going to replace
the skb_frag_t with the bio_vec.  This patch increases the size of
skb_frag_t on 32-bit machines from 8 bytes to 12 bytes.  The size is
unchanged on 64-bit machines.
Signed-off-by: NMatthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

In preparation for unifying the skb_frag and bio_vec, use the fine
accessors which already exist and use skb_frag_t instead of
struct skb_frag_struct.
Signed-off-by: NMatthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Retreives connection tracking zone, mark, label, and state from
a SKB.
Signed-off-by: NPaul Blakey <paulb@mellanox.com>
Signed-off-by: NMarcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Acked-by: NJiri Pirko <jiri@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Currently, TC offers the ability to match on the MPLS fields of a packet
through the use of the flow_dissector_key_mpls struct. However, as yet, TC
actions do not allow the modification or manipulation of such fields.

Add a new module that registers TC action ops to allow manipulation of
MPLS. This includes the ability to push and pop headers as well as modify
the contents of new or existing headers. A further action to decrement the
TTL field of an MPLS header is also provided with a new helper added to
support this.

Examples of the usage of the new action with flower rules to push and pop
MPLS labels are:

tc filter add dev eth0 protocol ip parent ffff: flower \
    action mpls push protocol mpls_uc label 123  \
    action mirred egress redirect dev eth1

tc filter add dev eth0 protocol mpls_uc parent ffff: flower \
    action mpls pop protocol ipv4  \
    action mirred egress redirect dev eth1
Signed-off-by: NJohn Hurley <john.hurley@netronome.com>
Reviewed-by: NJakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: NSimon Horman <simon.horman@netronome.com>
Reviewed-by: NWillem de Bruijn <willemb@google.com>
Acked-by: NCong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Open vSwitch allows the updating of an existing MPLS header on a packet.
In preparation for supporting similar functionality in TC, move this to a
common skb helper function.
Signed-off-by: NJohn Hurley <john.hurley@netronome.com>
Reviewed-by: NJakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: NSimon Horman <simon.horman@netronome.com>
Reviewed-by: NWillem de Bruijn <willemb@google.com>
Acked-by: NCong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Open vSwitch provides code to pop an MPLS header to a packet. In
preparation for supporting this in TC, move the pop code to an skb helper
that can be reused.

Remove the, now unused, update_ethertype static function from OvS.
Signed-off-by: NJohn Hurley <john.hurley@netronome.com>
Reviewed-by: NJakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: NSimon Horman <simon.horman@netronome.com>
Reviewed-by: NWillem de Bruijn <willemb@google.com>
Acked-by: NCong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Open vSwitch provides code to push an MPLS header to a packet. In
preparation for supporting this in TC, move the push code to an skb helper
that can be reused.
Signed-off-by: NJohn Hurley <john.hurley@netronome.com>
Reviewed-by: NJakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: NSimon Horman <simon.horman@netronome.com>
Reviewed-by: NWillem de Bruijn <willemb@google.com>
Acked-by: NCong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

skb_warn_bad_offload and netdev_rx_csum_fault trigger on hard to debug
issues. Dump more state and the header.

Optionally dump the entire packet and linear segment. This is required
to debug checksum bugs that may include bytes past skb_tail_pointer().

Both call sites call this function inside a net_ratelimit() block.
Limit full packet log further to a hard limit of can_dump_full (5).

Based on an earlier patch by Cong Wang, see link below.

Changes v1 -> v2
  - dump frag_list only on full_pkt

Link: https://patchwork.ozlabs.org/patch/1000841/Signed-off-by: NWillem de Bruijn <willemb@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

the check parameter is never used
Signed-off-by: NLi RongQing <lirongqing@baidu.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Add new key meta that contains ingress ifindex value and add a function
to dissect this from skb. The key and function is prepared to cover
other potential skb metadata values dissection.
Signed-off-by: NJiri Pirko <jiri@mellanox.com>
Signed-off-by: NIdo Schimmel <idosch@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

If strparser gets cornered into starting a new message from
an sk_buff which already has frags, it will allocate a new
skb to become the "wrapper" around the fragments of the
message.

This new skb does not inherit any metadata fields.  In case
of TLS offload this may lead to unnecessarily re-encrypting
the message, as skb->decrypted is not set for the wrapper skb.

Try to be conservative and copy all fields of old skb
strparser's user may reasonably need.
Signed-off-by: NJakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: NDirk van der Merwe <dirk.vandermerwe@netronome.com>
Reviewed-by: NSimon Horman <simon.horman@netronome.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Based on 1 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license as published by
  the free software foundation either version 2 of the license or at
  your option any later version

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 3029 file(s).
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Reviewed-by: NAllison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.deSigned-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

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: 5cd8d46e ("packet: copy user buffers before orphan or clone")
Signed-off-by: NWillem de Bruijn <willemb@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

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: NStanislav Fomichev <sdf@google.com>
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>

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: NStanislav Fomichev <sdf@google.com>
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>

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: NStanislav Fomichev <sdf@google.com>
Reviewed-by: NSaeed Mahameed <saeedm@mellanox.com>
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>

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: NStanislav Fomichev <sdf@google.com>
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>

We are discouraging the use of BUG() these days, remove the
unused ASSERT macros from skbuff.h.
Signed-off-by: NJakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: NDirk van der Merwe <dirk.vandermerwe@netronome.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

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: NJesper Dangaard Brouer <brouer@redhat.com>
Acked-by: NSong Liu <songliubraving@fb.com>
Acked-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NAlexei Starovoitov <ast@kernel.org>

After commit a297569f ("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: NPaolo Abeni <pabeni@redhat.com>
Acked-by: NWillem de Bruijn <willemb@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

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: NFlorian Westphal <fw@strlen.de>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

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: NPedro Tammela <pctammela@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

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: b90efd22 ("bpf: only adjust gso_size on bytestream protocols")
Signed-off-by: NWillem de Bruijn <willemb@google.com>
Acked-by: NYonghong Song <yhs@fb.com>
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>

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: NMaxim Mikityanskiy <maximmi@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

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: bfd5f4a3 ("packet: Add GSO/csum offload support.")
Fixes: f43798c2 ("tun: Allow GSO using virtio_net_hdr")
Reported-by: Nsyzbot <syzkaller@googlegroups.com>
Signed-off-by: NWillem de Bruijn <willemb@google.com>
Reviewed-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

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: NBrian Norris <briannorris@chromium.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

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 d02f51cb ("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: bec1f6f6 ("udp: generate gso with UDP_SEGMENT")
Signed-off-by: NWillem de Bruijn <willemb@google.com>
Signed-off-by: NAlexei Starovoitov <ast@kernel.org>

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: NDeepa Dinamani <deepa.kernel@gmail.com>
Acked-by: NWillem 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: NDavid S. Miller <davem@davemloft.net>

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: NDeepa Dinamani <deepa.kernel@gmail.com>
Acked-by: NWillem de Bruijn <willemb@google.com>
Cc: isdn@linux-pingi.de
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This way, we can reuse it for flow dissector in BPF_PROG_TEST_RUN.

No functional changes.
Signed-off-by: NStanislav Fomichev <sdf@google.com>
Acked-by: NSong Liu <songliubraving@fb.com>
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>

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: NRoss Lagerwall <ross.lagerwall@citrix.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

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: NOtto Sabart <ottosabart@seberm.com>
Acked-by: NDavid S. Miller <davem@davemloft.net>
Signed-off-by: NJonathan Corbet <corbet@lwn.net>

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: NPaolo Abeni <pabeni@redhat.com>
Acked-by: NFlorian Westphal <fw@strlen.de>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

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: NFlorian Westphal <fw@strlen.de>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

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: NFlorian Westphal <fw@strlen.de>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>