Skb_gso_segment() uses skb control block during segmentation.
This patch adds 32-bytes room for previous control block which
will be copied into all resulting segments.

This patch fixes kernel crash during fragmenting forwarded packets.
Fragmentation requires valid IP CB in skb for clearing ip options.
Also patch removes custom save/restore in ovs code, now it's redundant.
Signed-off-by: NKonstantin Khlebnikov <koct9i@gmail.com>
Link: http://lkml.kernel.org/r/CALYGNiP-0MZ-FExV2HutTvE9U-QQtkKSoE--KN=JQE5STYsjAA@mail.gmail.comSigned-off-by: NDavid S. Miller <davem@davemloft.net>

Add a small helper skb_postpush_rcsum() and fix up redirect locations
that need CHECKSUM_COMPLETE fixups on ingress. dev_forward_skb() expects
a proper csum that covers also Ethernet header, f.e. since 2c26d34b
("net/core: Handle csum for CHECKSUM_COMPLETE VXLAN forwarding"), we
also do skb_postpull_rcsum() after pulling Ethernet header off via
eth_type_trans().

When using eBPF in a netns setup f.e. with vxlan in collect metadata mode,
I can trigger the following csum issue with an IPv6 setup:

  [  505.144065] dummy1: hw csum failure
  [...]
  [  505.144108] Call Trace:
  [  505.144112]  <IRQ>  [<ffffffff81372f08>] dump_stack+0x44/0x5c
  [  505.144134]  [<ffffffff81607cea>] netdev_rx_csum_fault+0x3a/0x40
  [  505.144142]  [<ffffffff815fee3f>] __skb_checksum_complete+0xcf/0xe0
  [  505.144149]  [<ffffffff816f0902>] nf_ip6_checksum+0xb2/0x120
  [  505.144161]  [<ffffffffa08c0e0e>] icmpv6_error+0x17e/0x328 [nf_conntrack_ipv6]
  [  505.144170]  [<ffffffffa0898eca>] ? ip6t_do_table+0x2fa/0x645 [ip6_tables]
  [  505.144177]  [<ffffffffa08c0725>] ? ipv6_get_l4proto+0x65/0xd0 [nf_conntrack_ipv6]
  [  505.144189]  [<ffffffffa06c9a12>] nf_conntrack_in+0xc2/0x5a0 [nf_conntrack]
  [  505.144196]  [<ffffffffa08c039c>] ipv6_conntrack_in+0x1c/0x20 [nf_conntrack_ipv6]
  [  505.144204]  [<ffffffff8164385d>] nf_iterate+0x5d/0x70
  [  505.144210]  [<ffffffff816438d6>] nf_hook_slow+0x66/0xc0
  [  505.144218]  [<ffffffff816bd302>] ipv6_rcv+0x3f2/0x4f0
  [  505.144225]  [<ffffffff816bca40>] ? ip6_make_skb+0x1b0/0x1b0
  [  505.144232]  [<ffffffff8160b77b>] __netif_receive_skb_core+0x36b/0x9a0
  [  505.144239]  [<ffffffff8160bdc8>] ? __netif_receive_skb+0x18/0x60
  [  505.144245]  [<ffffffff8160bdc8>] __netif_receive_skb+0x18/0x60
  [  505.144252]  [<ffffffff8160ccff>] process_backlog+0x9f/0x140
  [  505.144259]  [<ffffffff8160c4a5>] net_rx_action+0x145/0x320
  [...]

What happens is that on ingress, we push Ethernet header back in, either
from cls_bpf or right before skb_do_redirect(), but without updating csum.
The "hw csum failure" can be fixed by using the new skb_postpush_rcsum()
helper for the dev_forward_skb() case to correct the csum diff again.

Thanks to Hannes Frederic Sowa for the csum_partial() idea!

Fixes: 3896d655 ("bpf: introduce bpf_clone_redirect() helper")
Fixes: 27b29f63 ("bpf: add bpf_redirect() helper")
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>
Acked-by: NAlexei Starovoitov <ast@kernel.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Add specifics and details the description of the interface between
the stack and drivers for doing checksum offload. This description
is meant to be as specific and complete as possible.
Signed-off-by: NTom Herbert <tom@herbertland.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Same thing as skb_transport_offset but returns the offset of the inner
transport header (when skb->encpasulation is set).
Signed-off-by: NTom Herbert <tom@herbertland.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch fix a typo found within comment of skb_fclone_busy.
Signed-off-by: NMasanari Iida <standby24x7@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The __skb_recv_datagram routine in core/ datagram.c provides a general
skb reception factility supposed to be utilized by protocol modules
providing datagram sockets. It encompasses both the actual recvmsg code
and a surrounding 'sleep until data is available' loop. This is
inconvenient if a protocol module has to use additional locking in order
to maintain some per-socket state the generic datagram socket code is
unaware of (as the af_unix code does). The patch below moves the recvmsg
proper code into a new __skb_try_recv_datagram routine which doesn't
sleep and renames wait_for_more_packets to
__skb_wait_for_more_packets, both routines being exported interfaces. The
original __skb_recv_datagram routine is reimplemented on top of these
two functions such that its user-visible behaviour remains unchanged.
Signed-off-by: NRainer Weikusat <rweikusat@mobileactivedefense.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

skb->sender_cpu and skb->napi_id share a common storage,
and we had various bugs about this.

We had to call skb_sender_cpu_clear() in some places to
not leave a prior skb->napi_id and fool netdev_pick_tx()

As suggested by Alexei, we could split the space so that
these errors can not happen.

0 value being reserved as the common (not initialized) value,
let's reserve [1 .. NR_CPUS] range for valid sender_cpu,
and [NR_CPUS+1 .. ~0U] for valid napi_id.

This will allow proper busy polling support over tunnels.
Signed-off-by: NEric Dumazet <edumazet@google.com>
Suggested-by: NAlexei Starovoitov <ast@kernel.org>
Acked-by: NAlexei Starovoitov <ast@kernel.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

mm, page_alloc: distinguish between being unable to sleep, unwilling to sleep and avoiding waking kswapd

__GFP_WAIT has been used to identify atomic context in callers that hold
spinlocks or are in interrupts.  They are expected to be high priority and
have access one of two watermarks lower than "min" which can be referred
to as the "atomic reserve".  __GFP_HIGH users get access to the first
lower watermark and can be called the "high priority reserve".

Over time, callers had a requirement to not block when fallback options
were available.  Some have abused __GFP_WAIT leading to a situation where
an optimisitic allocation with a fallback option can access atomic
reserves.

This patch uses __GFP_ATOMIC to identify callers that are truely atomic,
cannot sleep and have no alternative.  High priority users continue to use
__GFP_HIGH.  __GFP_DIRECT_RECLAIM identifies callers that can sleep and
are willing to enter direct reclaim.  __GFP_KSWAPD_RECLAIM to identify
callers that want to wake kswapd for background reclaim.  __GFP_WAIT is
redefined as a caller that is willing to enter direct reclaim and wake
kswapd for background reclaim.

This patch then converts a number of sites

o __GFP_ATOMIC is used by callers that are high priority and have memory
  pools for those requests. GFP_ATOMIC uses this flag.

o Callers that have a limited mempool to guarantee forward progress clear
  __GFP_DIRECT_RECLAIM but keep __GFP_KSWAPD_RECLAIM. bio allocations fall
  into this category where kswapd will still be woken but atomic reserves
  are not used as there is a one-entry mempool to guarantee progress.

o Callers that are checking if they are non-blocking should use the
  helper gfpflags_allow_blocking() where possible. This is because
  checking for __GFP_WAIT as was done historically now can trigger false
  positives. Some exceptions like dm-crypt.c exist where the code intent
  is clearer if __GFP_DIRECT_RECLAIM is used instead of the helper due to
  flag manipulations.

o Callers that built their own GFP flags instead of starting with GFP_KERNEL
  and friends now also need to specify __GFP_KSWAPD_RECLAIM.

The first key hazard to watch out for is callers that removed __GFP_WAIT
and was depending on access to atomic reserves for inconspicuous reasons.
In some cases it may be appropriate for them to use __GFP_HIGH.

The second key hazard is callers that assembled their own combination of
GFP flags instead of starting with something like GFP_KERNEL.  They may
now wish to specify __GFP_KSWAPD_RECLAIM.  It's almost certainly harmless
if it's missed in most cases as other activity will wake kswapd.
Signed-off-by: NMel Gorman <mgorman@techsingularity.net>
Acked-by: NVlastimil Babka <vbabka@suse.cz>
Acked-by: NMichal Hocko <mhocko@suse.com>
Acked-by: NJohannes Weiner <hannes@cmpxchg.org>
Cc: Christoph Lameter <cl@linux.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Vitaly Wool <vitalywool@gmail.com>
Cc: Rik van Riel <riel@redhat.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

a helper to prepare the first main RACK patch.
Signed-off-by: NYuchung Cheng <ycheng@google.com>
Signed-off-by: NNeal Cardwell <ncardwell@google.com>
Signed-off-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Earlier patch 6ae459bd tried to detect void ckecksum partial
skb by comparing pull length to checksum offset. But it does
not work for all cases since checksum-offset depends on
updates to skb->data.

Following patch fixes it by validating checksum start offset
after skb-data pointer is updated. Negative value of checksum
offset start means there is no need to checksum.

Fixes: 6ae459bd ("skbuff: Fix skb checksum flag on skb pull")
Reported-by: NAndrew Vagin <avagin@odin.com>
Signed-off-by: NPravin B Shelar <pshelar@nicira.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

VXLAN device can receive skb with checksum partial. But the checksum
offset could be in outer header which is pulled on receive. This results
in negative checksum offset for the skb. Such skb can cause the assert
failure in skb_checksum_help(). Following patch fixes the bug by setting
checksum-none while pulling outer header.

Following is the kernel panic msg from old kernel hitting the bug.

------------[ cut here ]------------
kernel BUG at net/core/dev.c:1906!
RIP: 0010:[<ffffffff81518034>] skb_checksum_help+0x144/0x150
Call Trace:
<IRQ>
[<ffffffffa0164c28>] queue_userspace_packet+0x408/0x470 [openvswitch]
[<ffffffffa016614d>] ovs_dp_upcall+0x5d/0x60 [openvswitch]
[<ffffffffa0166236>] ovs_dp_process_packet_with_key+0xe6/0x100 [openvswitch]
[<ffffffffa016629b>] ovs_dp_process_received_packet+0x4b/0x80 [openvswitch]
[<ffffffffa016c51a>] ovs_vport_receive+0x2a/0x30 [openvswitch]
[<ffffffffa0171383>] vxlan_rcv+0x53/0x60 [openvswitch]
[<ffffffffa01734cb>] vxlan_udp_encap_recv+0x8b/0xf0 [openvswitch]
[<ffffffff8157addc>] udp_queue_rcv_skb+0x2dc/0x3b0
[<ffffffff8157b56f>] __udp4_lib_rcv+0x1cf/0x6c0
[<ffffffff8157ba7a>] udp_rcv+0x1a/0x20
[<ffffffff8154fdbd>] ip_local_deliver_finish+0xdd/0x280
[<ffffffff81550128>] ip_local_deliver+0x88/0x90
[<ffffffff8154fa7d>] ip_rcv_finish+0x10d/0x370
[<ffffffff81550365>] ip_rcv+0x235/0x300
[<ffffffff8151ba1d>] __netif_receive_skb+0x55d/0x620
[<ffffffff8151c360>] netif_receive_skb+0x80/0x90
[<ffffffff81459935>] virtnet_poll+0x555/0x6f0
[<ffffffff8151cd04>] net_rx_action+0x134/0x290
[<ffffffff810683d8>] __do_softirq+0xa8/0x210
[<ffffffff8162fe6c>] call_softirq+0x1c/0x30
[<ffffffff810161a5>] do_softirq+0x65/0xa0
[<ffffffff810687be>] irq_exit+0x8e/0xb0
[<ffffffff81630733>] do_IRQ+0x63/0xe0
[<ffffffff81625f2e>] common_interrupt+0x6e/0x6e
Reported-by: NAnupam Chanda <achanda@vmware.com>
Signed-off-by: NPravin B Shelar <pshelar@nicira.com>
Acked-by: NTom Herbert <tom@herbertland.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

We can't re-use the physoutdev storage area.

1.  When using NFQUEUE in PREROUTING, we attempt to bump a bogus
refcnt since nf_bridge->physoutdev is garbage (ipv4/ipv6 address)

2. for same reason, we crash in physdev match in FORWARD or later if
skb is routed instead of bridged.

This increases nf_bridge_info to 40 bytes, but we have no other choice.

Fixes: 72b1e5e4 ("netfilter: bridge: reduce nf_bridge_info to 32 bytes again")
Reported-by: NSander Eikelenboom <linux@eikelenboom.it>
Signed-off-by: NFlorian Westphal <fw@strlen.de>
Signed-off-by: NPablo Neira Ayuso <pablo@netfilter.org>

Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Commit c6cc1ca7 ("flowi: Abstract out functions to get flow hash
based on flowi") introduced a bug in __skb_set_sw_hash where we
require a dependency on evaluating arguments in a function in order.
There is no such ordering enforced in C, so this incorrect. This
patch fixes that by splitting out the arguments. This bug was
found via a compiler warning that keys may be uninitialized.
Signed-off-by: NTom Herbert <tom@herbertland.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The flags argument will allow control of the dissection process (for
instance whether to parse beyond L3).
Signed-off-by: NTom Herbert <tom@herbertland.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Create __get_hash_from_flowi6 and __get_hash_from_flowi4 to get the
flow keys and hash based on flowi structures. These are called by
__skb_get_hash_flowi6 and __skb_get_hash_flowi4. Also, created
get_hash_from_flowi6 and get_hash_from_flowi4 which can be called
when just the hash value for a flowi is needed.
Signed-off-by: NTom Herbert <tom@herbertland.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Move __skb_set_sw_hash to skbuff.h and add __skb_set_hash which is
a common method (between __skb_set_sw_hash and skb_set_hash) to set
the hash in an skbuff.

Also, move skb_clear_hash to be closer to __skb_set_hash.
Signed-off-by: NTom Herbert <tom@herbertland.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Move the flow dissector functions that are specific to skbuffs into
skbuff.h out of flow_dissector.h. This makes flow_dissector.h have
no dependencies on skbuff.h.
Signed-off-by: NTom Herbert <tom@herbertland.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Commit c48a11c7 ("netvm: propagate page->pfmemalloc to skb") added
checks for page->pfmemalloc to __skb_fill_page_desc():

        if (page->pfmemalloc && !page->mapping)
                skb->pfmemalloc = true;

It assumes page->mapping == NULL implies that page->pfmemalloc can be
trusted.  However, __delete_from_page_cache() can set set page->mapping
to NULL and leave page->index value alone.  Due to being in union, a
non-zero page->index will be interpreted as true page->pfmemalloc.

So the assumption is invalid if the networking code can see such a page.
And it seems it can.  We have encountered this with a NFS over loopback
setup when such a page is attached to a new skbuf.  There is no copying
going on in this case so the page confuses __skb_fill_page_desc which
interprets the index as pfmemalloc flag and the network stack drops
packets that have been allocated using the reserves unless they are to
be queued on sockets handling the swapping which is the case here and
that leads to hangs when the nfs client waits for a response from the
server which has been dropped and thus never arrive.

The struct page is already heavily packed so rather than finding another
hole to put it in, let's do a trick instead.  We can reuse the index
again but define it to an impossible value (-1UL).  This is the page
index so it should never see the value that large.  Replace all direct
users of page->pfmemalloc by page_is_pfmemalloc which will hide this
nastiness from unspoiled eyes.

The information will get lost if somebody wants to use page->index
obviously but that was the case before and the original code expected
that the information should be persisted somewhere else if that is
really needed (e.g.  what SLAB and SLUB do).

[akpm@linux-foundation.org: fix blooper in slub]
Fixes: c48a11c7 ("netvm: propagate page->pfmemalloc to skb")
Signed-off-by: NMichal Hocko <mhocko@suse.com>
Debugged-by: NVlastimil Babka <vbabka@suse.com>
Debugged-by: NJiri Bohac <jbohac@suse.com>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: David Miller <davem@davemloft.net>
Acked-by: NMel Gorman <mgorman@suse.de>
Cc: <stable@vger.kernel.org>	[3.6+]
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

After "62bccb8c net-timestamp: Make the clone operation stand-alone from phy
timestamping" the hwtstamps parameter of skb_complete_tx_timestamp() may no
longer be NULL.
Signed-off-by: NBenjamin Poirier <bpoirier@suse.com>
Cc: Alexander Duyck <alexander.h.duyck@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Add skb_get_hash_flowi6 and skb_get_hash_flowi4 which derive an sk_buff
hash from flowi6 and flowi4 structures respectively. These functions
can be called when creating a packet in the output path where the new
sk_buff does not yet contain a fully formed packet that is parsable by
flow dissector.
Signed-off-by: NTom Herbert <tom@herbertland.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

We can use union for most of the temporary cruft (original ipv4/ipv6
address, source mac, physoutdev) since they're used during different
stages of br netfilter traversal.

Also get rid of the last two ->mask users.

Shrinks struct from 48 to 32 on 64bit arch.
Signed-off-by: NFlorian Westphal <fw@strlen.de>
Signed-off-by: NPablo Neira Ayuso <pablo@netfilter.org>

Allows putting a VXLAN device into a new flow-based mode in which
skbs with a ip_tunnel_info dst metadata attached will be encapsulated
according to the instructions stored in there with the VXLAN device
defaults taken into consideration.

Similar on the receive side, if the VXLAN_F_COLLECT_METADATA flag is
set, the packet processing will populate a ip_tunnel_info struct for
each packet received and attach it to the skb using the new metadata
dst.  The metadata structure will contain the outer header and tunnel
header fields which have been stripped off. Layers further up in the
stack such as routing, tc or netfitler can later match on these fields
and perform forwarding. It is the responsibility of upper layers to
ensure that the flag is set if the metadata is needed. The flag limits
the additional cost of metadata collecting based on demand.

This prepares the VXLAN device to be steered by the routing and other
subsystems which allows to support encapsulation for a large number
of tunnel endpoints and tunnel ids through a single net_device which
improves the scalability.

It also allows for OVS to leverage this mode which in turn allows for
the removal of the OVS specific VXLAN code.

Because the skb is currently scrubed in vxlan_rcv(), the attachment of
the new dst metadata is postponed until after scrubing which requires
the temporary addition of a new member to vxlan_metadata. This member
is removed again in a later commit after the indirect VXLAN receive API
has been removed.
Signed-off-by: NThomas Graf <tgraf@suug.ch>
Signed-off-by: NPravin B Shelar <pshelar@nicira.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

It's not used anywhere.
Signed-off-by: NJiri Benc <jbenc@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Just before queuing skb for xmit on port, check if skb has been marked by
switchdev port driver as already fordwarded by device.  If so, drop skb.  A
non-zero skb->offload_fwd_mark field is set by the switchdev port
driver/device on ingress to indicate the skb has already been forwarded by
the device to egress ports with matching dev->skb_mark.  The switchdev port
driver would assign a non-zero dev->offload_skb_mark for each device port
netdev during registration, for example.
Signed-off-by: NScott Feldman <sfeldma@gmail.com>
Acked-by: NJiri Pirko <jiri@resnulli.us>
Acked-by: NRoopa Prabhu <roopa@cumulusnetworks.com>
Acked-by: NNicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

__skb_header_pointer() returns a pointer that must be checked.

Fixes infinite loop reported by Alexei, and add __must_check to
catch these errors earlier.

Fixes: 6a74fcf4 ("flow_dissector: add support for dst, hop-by-hop and routing ext hdrs")
Reported-by: NAlexei Starovoitov <alexei.starovoitov@gmail.com>
Tested-by: NAlexei Starovoitov <alexei.starovoitov@gmail.com>
Signed-off-by: NEric Dumazet <edumazet@google.com>
Acked-by: NTom Herbert <tom@herbertland.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Currently frag_max_size is member of br_input_skb_cb and copied back and
forth using IPCB(skb) and BR_INPUT_SKB_CB(skb) each time it is changed or
used.

Attach frag_max_size to nf_bridge_info and set value in pre_routing and
forward functions. Use its value in forward and xmit functions.
Signed-off-by: NBernhard Thaler <bernhard.thaler@wvnet.at>
Signed-off-by: NPablo Neira Ayuso <pablo@netfilter.org>

IPv4 iptables allows to REDIRECT/DNAT/SNAT any traffic over a bridge.

e.g. REDIRECT
$ sysctl -w net.bridge.bridge-nf-call-iptables=1
$ iptables -t nat -A PREROUTING -p tcp -m tcp --dport 8080 \
  -j REDIRECT --to-ports 81

This does not work with ip6tables on a bridge in NAT66 scenario
because the REDIRECT/DNAT/SNAT is not correctly detected.

The bridge pre-routing (finish) netfilter hook has to check for a possible
redirect and then fix the destination mac address. This allows to use the
ip6tables rules for local REDIRECT/DNAT/SNAT REDIRECT similar to the IPv4
iptables version.

e.g. REDIRECT
$ sysctl -w net.bridge.bridge-nf-call-ip6tables=1
$ ip6tables -t nat -A PREROUTING -p tcp -m tcp --dport 8080 \
  -j REDIRECT --to-ports 81

This patch makes it possible to use IPv6 NAT66 on a bridge. It was tested
on a bridge with two interfaces using SNAT/DNAT NAT66 rules.
Reported-by: NArtie Hamilton <artiemhamilton@yahoo.com>
Signed-off-by: NSven Eckelmann <sven@open-mesh.com>
[bernhard.thaler@wvnet.at: rebased, add indirect call to ip6_route_input()]
[bernhard.thaler@wvnet.at: rebased, split into separate patches]
Signed-off-by: NBernhard Thaler <bernhard.thaler@wvnet.at>
Signed-off-by: NPablo Neira Ayuso <pablo@netfilter.org>

This patch changes flow hashing to use jhash2 over the flow_keys
structure instead just doing jhash_3words over src, dst, and ports.
This method will allow us take more input into the hashing function
so that we can include full IPv6 addresses, VLAN, flow labels etc.
without needing to resort to xor'ing which makes for a poor hash.
Acked-by: NJiri Pirko <jiri@resnulli.us>
Signed-off-by: NTom Herbert <tom@herbertland.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Prepare skb_splice_bits to be able to deal with AF_UNIX sockets.

AF_UNIX sockets don't use lock_sock/release_sock and thus we have to
use a callback to make the locking and unlocking configureable.
Signed-off-by: NHannes Frederic Sowa <hannes@stressinduktion.org>
Acked-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NHannes Frederic Sowa <hannes@stressinduktion.org>
Acked-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This reverts commit c055d5b0.

There are two issues:
'dnat_took_place' made me think that this is related to
-j DNAT/MASQUERADE.

But thats only one part of the story.  This is also relevant for SNAT
when we undo snat translation in reverse/reply direction.

Furthermore, I originally wanted to do this mainly to avoid
storing ipv6 addresses once we make DNAT/REDIRECT work
for ipv6 on bridges.

However, I forgot about SNPT/DNPT which is stateless.

So we can't escape storing address for ipv6 anyway. Might as
well do it for ipv4 too.
Reported-and-tested-by: NBernhard Thaler <bernhard.thaler@wvnet.at>
Signed-off-by: NFlorian Westphal <fw@strlen.de>
Signed-off-by: NPablo Neira Ayuso <pablo@netfilter.org>

First one in __skb_checksum_validate_complete() fixes the following
(and other callers)

make C=2 CF=-D__CHECK_ENDIAN__ net/ipv4/tcp_ipv4.o
  CHECK   net/ipv4/tcp_ipv4.c
include/linux/skbuff.h:3052:24: warning: incorrect type in return expression (different base types)
include/linux/skbuff.h:3052:24:    expected restricted __sum16
include/linux/skbuff.h:3052:24:    got int

Second is fixing gso_make_checksum() :

  CHECK   net/ipv4/gre_offload.c
include/linux/skbuff.h:3360:14: warning: incorrect type in assignment (different base types)
include/linux/skbuff.h:3360:14:    expected unsigned short [unsigned] [usertype] csum
include/linux/skbuff.h:3360:14:    got restricted __sum16
include/linux/skbuff.h:3365:16: warning: incorrect type in return expression (different base types)
include/linux/skbuff.h:3365:16:    expected restricted __sum16
include/linux/skbuff.h:3365:16:    got unsigned short [unsigned] [usertype] csum

Fixes: 5a212329 ("net: Support for csum_bad in skbuff")
Fixes: 7e2b10c1 ("net: Support for multiple checksums with gso")
Signed-off-by: NEric Dumazet <edumazet@google.com>
CC: Tom Herbert <tom@herbertland.com>
Acked-by: NTom Herbert <tom@herbertland.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The neigh_header is only needed when we detect DNAT after prerouting
and neigh cache didn't have a mac address for us.

The output port has not been chosen yet so we can re-use the storage
area, bringing struct size down to 32 bytes on x86_64.
Signed-off-by: NFlorian Westphal <fw@strlen.de>
Signed-off-by: NPablo Neira Ayuso <pablo@netfilter.org>

Signed-off-by: NJiri Pirko <jiri@resnulli.us>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

__skb_tx_hash function has no relation to flow_dissect so just move it
to dev.c
Signed-off-by: NJiri Pirko <jiri@resnulli.us>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Since the definition of the function is in flow_dissector.c, it makes
sense to have the declaration in flow_dissector.h
Signed-off-by: NJiri Pirko <jiri@resnulli.us>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Since these functions are defined in flow_dissector.c, move header
declarations from skbuff.h into flow_dissector.h
Signed-off-by: NJiri Pirko <jiri@resnulli.us>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

add couple of empty lines on the way.
Signed-off-by: NJiri Pirko <jiri@resnulli.us>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This change adds a function called skb_free_frag which is meant to
compliment the function netdev_alloc_frag.  The general idea is to enable a
more lightweight version of page freeing since we don't actually need all
the overhead of a put_page, and we don't quite fit the model of __free_pages.
Signed-off-by: NAlexander Duyck <alexander.h.duyck@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>