inner_protocol was added to struct sk_buff in
0d89d203 ("MPLS: Add limited GSO support"),
which is scheduled to be included in v3.11.

That patch did not update __copy_skb_header to copy the inner_protocol.
Signed-off-by: NJoe Stringer <joe@wand.net.nz>
Signed-off-by: NSimon Horman <horms@verge.net.au>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The goal of this new function is to perform all needed cleanup before sending
an skb into another netns.
Signed-off-by: NNicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

commit 68c33163 ("v4 GRE: Add TCP segmentation offload for GRE")
added a possible skb leak, because it frees only the head of segment
list, in case a skb_linearize() call fails.

This patch adds a kfree_skb_list() helper to fix the bug.
Signed-off-by: NEric Dumazet <edumazet@google.com>
Cc: Pravin B Shelar <pshelar@nicira.com>
Cc: Daniel Borkmann <dborkman@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Callers of skb_seq_read() are currently forced to call skb_abort_seq_read()
even when consuming all the data because the last call to skb_seq_read (the
one that returns 0 to indicate the end) fails to unmap the last fragment page.

With this patch callers will be allowed to traverse the SKB data by calling
skb_prepare_seq_read() once and repeatedly calling skb_seq_read() as originally
intended (and documented in the original commit 677e90ed), that is, only call
skb_abort_seq_read() if the sequential read is actually aborted.
Signed-off-by: NWedson Almeida Filho <wedsonaf@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Since commit 1a37e412(net: Use 16bits for *_headers fields of struct
skbuff), skb->*_header are relative to skb->head,
so copy_skb_header() should not call skb_headers_offset_update() now,
and we should pass correct parameter to skb_headers_offset_update() in
pskb_expand_head() and skb_copy_expand().
Signed-off-by: NWeiping Pan <panweiping3@gmail.com>
Reviewed-by: NSimon Horman <horms@verge.net.au>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Adds an ndo_ll_poll method and the code that supports it.
This method can be used by low latency applications to busy-poll
Ethernet device queues directly from the socket code.
sysctl_net_ll_poll controls how many microseconds to poll.
Default is zero (disabled).
Individual protocol support will be added by subsequent patches.
Signed-off-by: NAlexander Duyck <alexander.h.duyck@intel.com>
Signed-off-by: NJesse Brandeburg <jesse.brandeburg@intel.com>
Signed-off-by: NEliezer Tamir <eliezer.tamir@linux.intel.com>
Acked-by: NEric Dumazet <edumazet@google.com>
Tested-by: NWillem de Bruijn <willemb@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Eric Dumazet spotted that we have to check skb->head instead
of skb->data as skb->head points to the beginning of the
data area of the skbuff. Similarly, we have to initialize the
skb->head pointer, not skb->data in __alloc_skb_head.

After this fix, netlink crashes in the release path of the
sk_buff, so let's fix that as well.

This bug was introduced in (0ebd0ac5 net: add function to
allocate sk_buff head without data area).
Reported-by: NEric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: NPablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

commit 1a37e412 (net: Use 16bits for *_headers
fields of struct skbuff) converts skb->*_header to u16,
some #if NET_SKBUFF_DATA_USES_OFFSET are now useless,
and to be safe, we could just use "X = (typeof(X)) ~0U;"
as suggested by David.

Cc: David S. Miller <davem@davemloft.net>
Cc: Simon Horman <horms@verge.net.au>
Signed-off-by: NCong Wang <amwang@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

net/core/skbuff.c: In function ‘__alloc_skb_head’:
net/core/skbuff.c:203:2: warning: large integer implicitly truncated to unsigned type [-Woverflow]
net/core/skbuff.c: In function ‘__alloc_skb’:
net/core/skbuff.c:279:2: warning: large integer implicitly truncated to unsigned type [-Woverflow]
net/core/skbuff.c:280:2: warning: large integer implicitly truncated to unsigned type [-Woverflow]
net/core/skbuff.c: In function ‘build_skb’:
net/core/skbuff.c:348:2: warning: large integer implicitly truncated to unsigned type [-Woverflow]
net/core/skbuff.c:349:2: warning: large integer implicitly truncated to unsigned type [-Woverflow]
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This is a generic solution to resolve a specific problem that I have observed.

If the encapsulation of an skb changes then ability to offload checksums
may also change. In particular it may be necessary to perform checksumming
in software.

An example of such a case is where a non-GRE packet is received but
is to be encapsulated and transmitted as GRE.

Another example relates to my proposed support for for packets
that are non-MPLS when received but MPLS when transmitted.

The cost of this change is that the value of the csum variable may be
checked when it previously was not. In the case where the csum variable is
true this is pure overhead. In the case where the csum variable is false it
leads to software checksumming, which I believe also leads to correct
checksums in transmitted packets for the cases described above.

Further analysis:

This patch relies on the return value of can_checksum_protocol()
being correct and in turn the return value of skb_network_protocol(),
used to provide the protocol parameter of can_checksum_protocol(),
being correct. It also relies on the features passed to skb_segment()
and in turn to can_checksum_protocol() being correct.

I believe that this problem has not been observed for VLANs because it
appears that almost all drivers, the exception being xgbe, set
vlan_features such that that the checksum offload support for VLAN packets
is greater than or equal to that of non-VLAN packets.

I wonder if the code in xgbe may be an oversight and the hardware does
support checksumming of VLAN packets.  If so it may be worth updating the
vlan_features of the driver as this patch will force such checksums to be
performed in software rather than hardware.
Signed-off-by: NSimon Horman <horms@verge.net.au>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When transmit timestamping is enabled at the socket level, record a
timestamp on packets written to a PACKET_TX_RING. Tx timestamps are
always looped to the application over the socket error queue. Software
timestamps are also written back into the packet frame header in the
packet ring.
Reported-by: NPaul Chavent <paul.chavent@onera.fr>
Signed-off-by: NWillem de Bruijn <willemb@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Add a function to allocate a sk_buff head without any data. This will
be used by memory mapped netlink to attach data from the mmaped area
to the skb.

Additionally change skb_release_all() to check whether the skb has a
data area to allow the skb destructor to clear the data pointer in case
only a head has been allocated.
Signed-off-by: NPatrick McHardy <kaber@trash.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Add a protocol argument to the VLAN packet tagging functions. In case of HW
tagging, we need that protocol available in the ndo_start_xmit functions,
so it is stored in a new field in the skb. The new field fits into a hole
(on 64 bit) and doesn't increase the sks's size.
Signed-off-by: NPatrick McHardy <kaber@trash.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

For untrusted packets with partial checksum, we need to set the transport header
for precise packet length estimation. We can just let skb_pratial_csum_set() to
do this to avoid extra call to skb_flow_dissect() and simplify the caller.

Cc: Eric Dumazet <edumazet@google.com>
Signed-off-by: NJason Wang <jasowang@redhat.com>
Acked-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch adds inner mac header. This will be used in next patch
to find tunner header length. Header len is required to copy tunnel
header to each gso segment.
This patch does not change any functionality.
Signed-off-by: NPravin B Shelar <pshelar@nicira.com>
Acked-by: NStephen Hemminger <stephen@networkplumber.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This function will be used in next VXLAN_GSO patch. This patch does
not change any functionality.
Signed-off-by: NPravin B Shelar <pshelar@nicira.com>
Acked-by: NStephen Hemminger <stephen@networkplumber.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Earlier SG was unset if CSUM was not available for given device to
force skb copy to avoid sending inconsistent csum.
Commit c9af6db4 (net: Fix possible wrong checksum generation)
added explicit flag to force copy to fix this issue.  Therefore
there is no need to link SG and CSUM, following patch kills this
link between there two features.

This patch is also required following patch in series.
Signed-off-by: NPravin B Shelar <pshelar@nicira.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

commit c9af6db4 (net: Fix possible wrong checksum generation)
has a suspicous piece:

	-       skb_shinfo(skb1)->gso_type = skb_shinfo(skb)->gso_type;
	-
	+       skb_shinfo(skb)->tx_flags = skb_shinfo(skb1)->tx_flags & SKBTX_SHARED_FRAG;

skb1 is the new skb, therefore should be on the left side of the assignment.
This patch fixes it.

Cc: Pravin B Shelar <pshelar@nicira.com>
Cc: David S. Miller <davem@davemloft.net>
Signed-off-by: NCong Wang <amwang@redhat.com>
Acked-by: NPravin B Shelar <pshelar@nicira.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Following patch adds GRE protocol offload handler so that
skb_gso_segment() can segment GRE packets.
SKB GSO CB is added to keep track of total header length so that
skb_segment can push entire header. e.g. in case of GRE, skb_segment
need to push inner and outer headers to every segment.
New NETIF_F_GRE_GSO feature is added for devices which support HW
GRE TSO offload. Currently none of devices support it therefore GRE GSO
always fall backs to software GSO.

[ Compute pkt_len before ip_local_out() invocation. -DaveM ]
Signed-off-by: NPravin B Shelar <pshelar@nicira.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Patch cef401de (net: fix possible wrong checksum
generation) fixed wrong checksum calculation but it broke TSO by
defining new GSO type but not a netdev feature for that type.
net_gso_ok() would not allow hardware checksum/segmentation
offload of such packets without the feature.

Following patch fixes TSO and wrong checksum. This patch uses
same logic that Eric Dumazet used. Patch introduces new flag
SKBTX_SHARED_FRAG if at least one frag can be modified by
the user. but SKBTX_SHARED_FRAG flag is kept in skb shared
info tx_flags rather than gso_type.

tx_flags is better compared to gso_type since we can have skb with
shared frag without gso packet. It does not link SHARED_FRAG to
GSO, So there is no need to define netdev feature for this.
Signed-off-by: NPravin B Shelar <pshelar@nicira.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

I get the following build error on next-20130213 due to the following
commit:

commit f05de73b ("skbuff: create
skb_panic() function and its wrappers").

It adds an argument called panic to a function that uses the BUG() macro
which tries to call panic, but the argument masks the panic() function
declaration, resulting in the following error (gcc 4.2.4):

net/core/skbuff.c In function 'skb_panic':
net/core/skbuff.c +126 : error: called object 'panic' is not a function

This is fixed by renaming the argument to msg.
Signed-off-by: NJames Hogan <james.hogan@imgtec.com>
Cc: Jean Sacren <sakiwit@gmail.com>
Cc: Jiri Pirko <jiri@resnulli.us>
Cc: David S. Miller <davem@davemloft.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Create skb_panic() function in lieu of both skb_over_panic() and
skb_under_panic() so that code duplication would be avoided. Update type
and variable name where necessary.

Jiri Pirko suggested using wrappers so that we would be able to keep the
fruits of the original code.
Signed-off-by: NJean Sacren <sakiwit@gmail.com>
Cc: Jiri Pirko <jiri@resnulli.us>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

In order to address the fact that some devices cannot support the full 32K
frag size we need to have the value accessible somewhere so that we can use it
to do comparisons against what the device can support.  As such I am moving
the values out of skbuff.c and into skbuff.h.
Signed-off-by: NAlexander Duyck <alexander.h.duyck@intel.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Use correct inner offset to set inner_network_offset.
Found by inspection.
Signed-off-by: NPravin B Shelar <pshelar@nicira.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Pravin Shelar mentioned that GSO could potentially generate
wrong TX checksum if skb has fragments that are overwritten
by the user between the checksum computation and transmit.

He suggested to linearize skbs but this extra copy can be
avoided for normal tcp skbs cooked by tcp_sendmsg().

This patch introduces a new SKB_GSO_SHARED_FRAG flag, set
in skb_shinfo(skb)->gso_type if at least one frag can be
modified by the user.

Typical sources of such possible overwrites are {vm}splice(),
sendfile(), and macvtap/tun/virtio_net drivers.

Tested:

$ netperf -H 7.7.8.84
MIGRATED TCP STREAM TEST from 0.0.0.0 (0.0.0.0) port 0 AF_INET to
7.7.8.84 () port 0 AF_INET
Recv   Send    Send
Socket Socket  Message  Elapsed
Size   Size    Size     Time     Throughput
bytes  bytes   bytes    secs.    10^6bits/sec

 87380  16384  16384    10.00    3959.52

$ netperf -H 7.7.8.84 -t TCP_SENDFILE
TCP SENDFILE TEST from 0.0.0.0 (0.0.0.0) port 0 AF_INET to 7.7.8.84 ()
port 0 AF_INET
Recv   Send    Send
Socket Socket  Message  Elapsed
Size   Size    Size     Time     Throughput
bytes  bytes   bytes    secs.    10^6bits/sec

 87380  16384  16384    10.00    3216.80

Performance of the SENDFILE is impacted by the extra allocation and
copy, and because we use order-0 pages, while the TCP_STREAM uses
bigger pages.
Reported-by: NPravin Shelar <pshelar@nicira.com>
Signed-off-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

commit 9ca1b22d (net: splice: avoid high order page splitting)
forgot that skb->head could need a copy into several page frags.

This could be the case for loopback traffic mostly.

Also remove now useless skb argument from linear_to_page()
and __splice_segment() prototypes.
Signed-off-by: NEric Dumazet <edumazet@google.com>
Cc: Willy Tarreau <w@1wt.eu>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

splice() can handle pages of any order, but network code tries hard to
split them in PAGE_SIZE units. Not quite successfully anyway, as
__splice_segment() assumed poff < PAGE_SIZE. This is true for
the skb->data part, not necessarily for the fragments.

This patch removes this logic to give the pages as they are in the skb.
Signed-off-by: NEric Dumazet <edumazet@google.com>
Cc: Willy Tarreau <w@1wt.eu>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

commit 9ca1b22d (net: splice: avoid high order page splitting)
forgot that skb->head could need a copy into several page frags.

This could be the case for loopback traffic mostly.

Also remove now useless skb argument from linear_to_page()
and __splice_segment() prototypes.
Signed-off-by: NEric Dumazet <edumazet@google.com>
Cc: Willy Tarreau <w@1wt.eu>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

We have skb_mac_header_was_set() helper to tell if mac_header
was set on a skb. We would like the same for transport_header.

__netif_receive_skb() doesn't reset the transport header if already
set by GRO layer.

Note that network stacks usually reset the transport header anyway,
after pulling the network header, so this change only allows
a followup patch to have more precise qdisc pkt_len computation
for GSO packets at ingress side.
Signed-off-by: NEric Dumazet <edumazet@google.com>
Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

splice() can handle pages of any order, but network code tries hard to
split them in PAGE_SIZE units. Not quite successfully anyway, as
__splice_segment() assumed poff < PAGE_SIZE. This is true for
the skb->data part, not necessarily for the fragments.

This patch removes this logic to give the pages as they are in the skb.
Signed-off-by: NEric Dumazet <edumazet@google.com>
Cc: Willy Tarreau <w@1wt.eu>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Sparse detected case where this local function should be static.
It may even allow some compiler optimizations.
Signed-off-by: NStephen Hemminger <shemminger@vyatta.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Use the new per task frag allocator in skb_append_datato_frags(),
to reduce number of frags and page allocator overhead.

Tested:
 ifconfig lo mtu 16436
 perf record netperf -t UDP_STREAM ; perf report

before :
 Throughput: 32928 Mbit/s
    51.79%  netperf  [kernel.kallsyms]  [k] copy_user_generic_string
     5.98%  netperf  [kernel.kallsyms]  [k] __alloc_pages_nodemask
     5.58%  netperf  [kernel.kallsyms]  [k] get_page_from_freelist
     5.01%  netperf  [kernel.kallsyms]  [k] __rmqueue
     3.74%  netperf  [kernel.kallsyms]  [k] skb_append_datato_frags
     1.87%  netperf  [kernel.kallsyms]  [k] prep_new_page
     1.42%  netperf  [kernel.kallsyms]  [k] next_zones_zonelist
     1.28%  netperf  [kernel.kallsyms]  [k] __inc_zone_state
     1.26%  netperf  [kernel.kallsyms]  [k] alloc_pages_current
     0.78%  netperf  [kernel.kallsyms]  [k] sock_alloc_send_pskb
     0.74%  netperf  [kernel.kallsyms]  [k] udp_sendmsg
     0.72%  netperf  [kernel.kallsyms]  [k] zone_watermark_ok
     0.68%  netperf  [kernel.kallsyms]  [k] __cpuset_node_allowed_softwall
     0.67%  netperf  [kernel.kallsyms]  [k] fib_table_lookup
     0.60%  netperf  [kernel.kallsyms]  [k] memcpy_fromiovecend
     0.55%  netperf  [kernel.kallsyms]  [k] __udp4_lib_lookup

 after:
  Throughput: 47185 Mbit/s
	61.74%	netperf  [kernel.kallsyms]	[k] copy_user_generic_string
	 2.07%	netperf  [kernel.kallsyms]	[k] prep_new_page
	 1.98%	netperf  [kernel.kallsyms]	[k] skb_append_datato_frags
	 1.02%	netperf  [kernel.kallsyms]	[k] sock_alloc_send_pskb
	 0.97%	netperf  [kernel.kallsyms]	[k] enqueue_task_fair
	 0.97%	netperf  [kernel.kallsyms]	[k] udp_sendmsg
	 0.91%	netperf  [kernel.kallsyms]	[k] __ip_route_output_key
	 0.88%	netperf  [kernel.kallsyms]	[k] __netif_receive_skb
	 0.87%	netperf  [kernel.kallsyms]	[k] fib_table_lookup
	 0.85%	netperf  [kernel.kallsyms]	[k] resched_task
	 0.78%	netperf  [kernel.kallsyms]	[k] __udp4_lib_lookup
	 0.77%	netperf  [kernel.kallsyms]	[k] _raw_spin_lock_irqsave
Signed-off-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

__copy_skb_header(nskb, p) already copied p->cb[], no need to copy
it again.
Signed-off-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch adds support in the kernel for offloading in the NIC Tx and Rx
checksumming for encapsulated packets (such as VXLAN and IP GRE).

For Tx encapsulation offload, the driver will need to set the right bits
in netdev->hw_enc_features. The protocol driver will have to set the
skb->encapsulation bit and populate the inner headers, so the NIC driver will
use those inner headers to calculate the csum in hardware.

For Rx encapsulation offload, the driver will need to set again the
skb->encapsulation flag and the skb->ip_csum to CHECKSUM_UNNECESSARY.
In that case the protocol driver should push the decapsulated packet up
to the stack, again with CHECKSUM_UNNECESSARY. In ether case, the protocol
driver should set the skb->encapsulation flag back to zero. Finally the
protocol driver should have NETIF_F_RXCSUM flag set in its features.
Signed-off-by: NJoseph Gasparakis <joseph.gasparakis@intel.com>
Signed-off-by: NPeter P Waskiewicz Jr <peter.p.waskiewicz.jr@intel.com>
Signed-off-by: NAlexander Duyck <alexander.h.duyck@intel.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

commit 2e71a6f8 (net: gro: selective flush of packets) added
a bug for skbs using frag_list. This part of the GRO stack is rarely
used, as it needs skb not using a page fragment for their skb->head.

Most drivers do use a page fragment, but some of them use GFP_KERNEL
allocations for the initial fill of their RX ring buffer.

napi_gro_flush() overwrite skb->prev that was used for these skb to
point to the last skb in frag_list.

Fix this using a separate field in struct napi_gro_cb to point to the
last fragment.
Signed-off-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Orphaning frags for zero copy skbs needs to allocate data in atomic
context so is has a chance to fail. If it does we currently discard
the skb which is safe, but we don't report anything to the caller,
so it can not recover by e.g. disabling zero copy.

Add an API to free skb reporting such errors: this is used
by tun in case orphaning frags fails.
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Even if skb is marked for zero copy, net core might still decide
to copy it later which is somewhat slower than a copy in user context:
besides copying the data we need to pin/unpin the pages.

Add a parameter reporting such cases through zero copy callback:
if this happens a lot, device can take this into account
and switch to copying in user context.

This patch updates all users but ignores the passed value for now:
it will be used by follow-up patches.
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Mike Kazantsev found 3.5 kernels and beyond were leaking memory,
and tracked the faulty commit to a1c7fff7 ("net:
netdev_alloc_skb() use build_skb()")

While this commit seems fine, it uncovered a bug introduced
in commit bad43ca8 ("net: introduce skb_try_coalesce()), in function
kfree_skb_partial()"):

If head is stolen, we free the sk_buff,
without removing references on secpath (skb->sp).

So IPsec + IP defrag/reassembly (using skb coalescing), or
TCP coalescing could leak secpath objects.

Fix this bug by calling skb_release_head_state(skb) to properly
release all possible references to linked objects.
Reported-by: NMike Kazantsev <mk.fraggod@gmail.com>
Signed-off-by: NEric Dumazet <edumazet@google.com>
Bisected-by: NMike Kazantsev <mk.fraggod@gmail.com>
Tested-by: NMike Kazantsev <mk.fraggod@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Over time, skb recycling infrastructure got litle interest and
many bugs. Generic rx path skb allocation is now using page
fragments for efficient GRO / TCP coalescing, and recyling
a tx skb for rx path is not worth the pain.

Last identified bug is that fat skbs can be recycled
and it can endup using high order pages after few iterations.

With help from Maxime Bizon, who pointed out that commit
87151b86 (net: allow pskb_expand_head() to get maximum tailroom)
introduced this regression for recycled skbs.

Instead of fixing this bug, lets remove skb recycling.

Drivers wanting really hot skbs should use build_skb() anyway,
to allocate/populate sk_buff right before netif_receive_skb()
Signed-off-by: NEric Dumazet <edumazet@google.com>
Cc: Maxime Bizon <mbizon@freebox.fr>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Commit ec47ea82(skb: Add inline helper for getting the skb end offset from
head) introduces this helper function, skb_end_offset(),
we should make use of it.
Signed-off-by: NWeiping Pan <wpan@redhat.com>
Acked-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>