Add GRO handlers for protocols that do UDP encapsulation, with the intent of
being able to coalesce packets which encapsulate packets belonging to
the same TCP session.

For GRO purposes, the destination UDP port takes the role of the ether type
field in the ethernet header or the next protocol in the IP header.

The UDP GRO handler will only attempt to coalesce packets whose destination
port is registered to have gro handler.

Use a mark on the skb GRO CB data to disallow (flush) running the udp gro receive
code twice on a packet. This solves the problem of udp encapsulated packets whose
inner VM packet is udp and happen to carry a port which has registered offloads.
Signed-off-by: NShlomo Pongratz <shlomop@mellanox.com>
Signed-off-by: NOr Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

These changes correct the following issues with jumbo frames on the
stmmac driver:

1) The Synopsys EMAC can be configured to support different FIFO
sizes at core configuration time. There's no way to query the
controller and know the FIFO size, so the driver needs to get this
information from the device tree in order to know how to correctly
handle MTU changes and setting up dma buffers. The default
max-frame-size is as currently used, which is the size of a jumbo
frame.

2) The driver was enabling Jumbo frames by default, but was not allocating
dma buffers of sufficient size to handle the maximum possible packet
size that could be received. This led to memory corruption since DMAs were
occurring beyond the extent of the allocated receive buffers for certain types
of network traffic.

kernel BUG at net/core/skbuff.c:126!
Internal error: Oops - BUG: 0 [#1] SMP ARM
Modules linked in:
CPU: 0 PID: 563 Comm: sockperf Not tainted 3.13.0-rc6-01523-gf7111b9 #31
task: ef35e580 ti: ef252000 task.ti: ef252000
PC is at skb_panic+0x60/0x64
LR is at skb_panic+0x60/0x64
pc : [<c03c7c3c>]    lr : [<c03c7c3c>]    psr: 60000113
sp : ef253c18  ip : 60000113  fp : 00000000
r10: ef3a5400  r9 : 00000ebc  r8 : ef3a546c
r7 : ee59f000  r6 : ee59f084  r5 : ee59ff40  r4 : ee59f140
r3 : 000003e2  r2 : 00000007  r1 : c0b9c420  r0 : 0000007d
Flags: nZCv  IRQs on  FIQs on  Mode SVC_32  ISA ARM  Segment user
Control: 10c5387d  Table: 2e8ac04a  DAC: 00000015
Process sockperf (pid: 563, stack limit = 0xef252248)
Stack: (0xef253c18 to 0xef254000)
3c00:                                                       00000ebc ee59f000
3c20: ee59f084 ee59ff40 ee59f140 c04a9cd8 ee8c50c0 00000ebc ee59ff40 00000000
3c40: ee59f140 c02d0ef0 00000056 ef1eda80 ee8c50c0 00000ebc 22bbef29 c0318f8c
3c60: 00000056 ef3a547c ffe2c716 c02c9c90 c0ba1298 ef3a5838 ef3a5838 ef3a5400
3c80: 000020c0 ee573840 000055cb ef3f2050 c053f0e0 c0319214 22b9b085 22d92813
3ca0: 00001c80 004b8e00 ef3a5400 ee573840 ef3f2064 22d92813 ef3f2064 000055cb
3cc0: ef3f2050 c031a19c ef252000 00000000 00000000 c0561bc0 00000000 ff00ffff
3ce0: c05621c0 ef3a5400 ef3f2064 ee573840 00000020 ef3f2064 000055cb ef3f2050
3d00: c053f0e0 c031cad0 c053e740 00000e60 00000000 00000000 ee573840 ef3a5400
3d20: ef0a6e00 00000000 ef3f2064 c032507c 00010000 00000020 c0561bc0 c0561bc0
3d40: ee599850 c032799c 00000000 ee573840 c055a380 ef3a5400 00000000 ef3f2064
3d60: ef3f2050 c032799c 0101c7c0 2b6755cb c059a280 c030e4d8 000055cb ffffffff
3d80: ee574fc0 c055a380 ee574000 ee573840 00002b67 ee573840 c03fe9c4 c053fa68
3da0: c055a380 00001f6f 00000000 ee573840 c053f0e0 c0304fdc ef0a6e01 ef3f2050
3dc0: ee573858 ef031000 ee573840 c03055d8 c0ba0c40 ef000f40 00100100 c053f0dc
3de0: c053ffdc c053f0f0 00000008 00000000 ef031000 c02da948 00001140 00000000
3e00: c0563c78 ef253e5f 00000020 ee573840 00000020 c053f0f0 ef313400 ee573840
3e20: c053f0e0 00000000 00000000 c05380c0 ef313400 00001000 00000015 c02df280
3e40: ee574000 ef001e00 00000000 00001080 00000042 005cd980 ef031500 ef031500
3e60: 00000000 c02df824 ef031500 c053e390 c0541084 f00b1e00 c05925e8 c02df864
3e80: 00001f5c ef031440 c053e390 c0278524 00000002 00000000 c0b9eb48 c02df280
3ea0: ee8c7180 00000100 c0542ca8 00000015 00000040 ef031500 ef031500 ef031500
3ec0: c027803c ef252000 00000040 000000ec c05380c0 c0b9eb40 c0b9eb48 c02df940
3ee0: ef060780 ffffa4dd c0564a9c c056343c 002e80a8 00000080 ef031500 00000001
3f00: c053808c ef252000 fffec100 00000003 00000004 002e80a8 0000000c c00258f0
3f20: 002e80a8 c005e704 00000005 00000100 c05634d0 c0538080 c05333e0 00000000
3f40: 0000000a c0565580 c05380c0 ffffa4dc c05434f4 00400100 00000004 c0534cd4
3f60: 00000098 00000000 fffec100 002e80a8 00000004 002e80a8 002a20e0 c0025da8
3f80: c0534cd4 c000f020 fffec10c c053ea60 ef253fb0 c0008530 0000ffe2 b6ef67f4
3fa0: 40000010 ffffffff 00000124 c0012f3c 0000ffe2 002e80f0 0000ffe2 00004000
3fc0: becb6338 becb6334 00000004 00000124 002e80a8 00000004 002e80a8 002a20e0
3fe0: becb6300 becb62f4 002773bb b6ef67f4 40000010 ffffffff 00000000 00000000
[<c03c7c3c>] (skb_panic+0x60/0x64) from [<c02d0ef0>] (skb_put+0x4c/0x50)
[<c02d0ef0>] (skb_put+0x4c/0x50) from [<c0318f8c>] (tcp_collapse+0x314/0x3ec)
[<c0318f8c>] (tcp_collapse+0x314/0x3ec) from [<c0319214>]
(tcp_try_rmem_schedule+0x1b0/0x3c4)
[<c0319214>] (tcp_try_rmem_schedule+0x1b0/0x3c4) from [<c031a19c>]
(tcp_data_queue+0x480/0xe6c)
[<c031a19c>] (tcp_data_queue+0x480/0xe6c) from [<c031cad0>]
(tcp_rcv_established+0x180/0x62c)
[<c031cad0>] (tcp_rcv_established+0x180/0x62c) from [<c032507c>]
(tcp_v4_do_rcv+0x13c/0x31c)
[<c032507c>] (tcp_v4_do_rcv+0x13c/0x31c) from [<c032799c>]
(tcp_v4_rcv+0x718/0x73c)
[<c032799c>] (tcp_v4_rcv+0x718/0x73c) from [<c0304fdc>]
(ip_local_deliver+0x98/0x274)
[<c0304fdc>] (ip_local_deliver+0x98/0x274) from [<c03055d8>]
(ip_rcv+0x420/0x758)
[<c03055d8>] (ip_rcv+0x420/0x758) from [<c02da948>]
(__netif_receive_skb_core+0x44c/0x5bc)
[<c02da948>] (__netif_receive_skb_core+0x44c/0x5bc) from [<c02df280>]
(netif_receive_skb+0x48/0xb4)
[<c02df280>] (netif_receive_skb+0x48/0xb4) from [<c02df824>]
(napi_gro_flush+0x70/0x94)
[<c02df824>] (napi_gro_flush+0x70/0x94) from [<c02df864>]
(napi_complete+0x1c/0x34)
[<c02df864>] (napi_complete+0x1c/0x34) from [<c0278524>]
(stmmac_poll+0x4e8/0x5c8)
[<c0278524>] (stmmac_poll+0x4e8/0x5c8) from [<c02df940>]
(net_rx_action+0xc4/0x1e4)
[<c02df940>] (net_rx_action+0xc4/0x1e4) from [<c00258f0>]
(__do_softirq+0x12c/0x2e8)
[<c00258f0>] (__do_softirq+0x12c/0x2e8) from [<c0025da8>] (irq_exit+0x78/0xac)
[<c0025da8>] (irq_exit+0x78/0xac) from [<c000f020>] (handle_IRQ+0x44/0x90)
[<c000f020>] (handle_IRQ+0x44/0x90) from [<c0008530>]
(gic_handle_irq+0x2c/0x5c)
[<c0008530>] (gic_handle_irq+0x2c/0x5c) from [<c0012f3c>]
(__irq_usr+0x3c/0x60)

3) The driver was setting the dma buffer size after allocating dma buffers,
which caused a system panic when changing the MTU.

BUG: Bad page state in process ifconfig  pfn:2e850
page:c0b72a00 count:0 mapcount:0 mapping:  (null) index:0x0
page flags: 0x200(arch_1)
Modules linked in:
CPU: 0 PID: 566 Comm: ifconfig Not tainted 3.13.0-rc6-01523-gf7111b9 #29
[<c001547c>] (unwind_backtrace+0x0/0xf8) from [<c00122dc>]
(show_stack+0x10/0x14)
[<c00122dc>] (show_stack+0x10/0x14) from [<c03c793c>] (dump_stack+0x70/0x88)
[<c03c793c>] (dump_stack+0x70/0x88) from [<c00b2620>] (bad_page+0xc8/0x118)
[<c00b2620>] (bad_page+0xc8/0x118) from [<c00b302c>]
(get_page_from_freelist+0x744/0x870)
[<c00b302c>] (get_page_from_freelist+0x744/0x870) from [<c00b40f4>]
(__alloc_pages_nodemask+0x118/0x86c)
[<c00b40f4>] (__alloc_pages_nodemask+0x118/0x86c) from [<c00b4858>]
(__get_free_pages+0x10/0x54)
[<c00b4858>] (__get_free_pages+0x10/0x54) from [<c00cba1c>]
(kmalloc_order_trace+0x24/0xa0)
[<c00cba1c>] (kmalloc_order_trace+0x24/0xa0) from [<c02d199c>]
(__kmalloc_reserve.isra.21+0x24/0x70)
[<c02d199c>] (__kmalloc_reserve.isra.21+0x24/0x70) from [<c02d240c>]
(__alloc_skb+0x68/0x13c)
[<c02d240c>] (__alloc_skb+0x68/0x13c) from [<c02d3930>]
(__netdev_alloc_skb+0x3c/0xe8)
[<c02d3930>] (__netdev_alloc_skb+0x3c/0xe8) from [<c0279378>]
(stmmac_open+0x63c/0x1024)
[<c0279378>] (stmmac_open+0x63c/0x1024) from [<c02e18cc>]
(__dev_open+0xa0/0xfc)
[<c02e18cc>] (__dev_open+0xa0/0xfc) from [<c02e1b40>]
(__dev_change_flags+0x94/0x158)
[<c02e1b40>] (__dev_change_flags+0x94/0x158) from [<c02e1c24>]
(dev_change_flags+0x18/0x48)
[<c02e1c24>] (dev_change_flags+0x18/0x48) from [<c0337bc0>]
(devinet_ioctl+0x638/0x700)
[<c0337bc0>] (devinet_ioctl+0x638/0x700) from [<c02c7aec>]
(sock_ioctl+0x64/0x290)
[<c02c7aec>] (sock_ioctl+0x64/0x290) from [<c0100890>]
(do_vfs_ioctl+0x78/0x5b8)
[<c0100890>] (do_vfs_ioctl+0x78/0x5b8) from [<c0100e0c>] (SyS_ioctl+0x3c/0x5c)
[<c0100e0c>] (SyS_ioctl+0x3c/0x5c) from [<c000e760>]

The fixes have been verified using reproducible, automated testing.
Signed-off-by: NVince Bridgers <vbridgers2013@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This change adds a parameter for the Synopsys 10/100/1000
stmmac Ethernet driver to configure the maximum frame
size supported by the EMAC driver. Synopsys allows the FIFO
sizes to be configured when the cores are built for a particular
device, but do not provide a way for the driver to read
information from the device about the maximum MTU size
supported as limited by the device's FIFO size.
Signed-off-by: NVince Bridgers <vbridgers2013@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Smatch complains because we are using an untrusted index into the
rxrpc_acks[] array.  It's just a read and it's only in the debug code,
but it's simple enough to add a check and fix it.
Signed-off-by: NDan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Replace deprecated 'vconfig' tool with 'ip' from 'iproute2'. Add
some beautifications like replacing 'ethernet' with 'Ethernet' and
removing unneeded spaces.
Signed-off-by: NYegor Yefremov <yegorslists@googlemail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Some ipv6 protocols cannot handle ipv4 addresses, so we must not allow
connecting and binding to them. sendmsg logic does already check msg->name
for this but must trust already connected sockets which could be set up
for connection to ipv4 address family.

Per-socket flag ipv6only is of no use here, as it is under users control
by setsockopt.
Signed-off-by: NHannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

- Uses ipv6_anycast_destination() in icmp6_send().
Suggested-by: NBill Fink <billfink@mindspring.com>
Signed-off-by: NFrancois-Xavier Le Bail <fx.lebail@yahoo.com>
Acked-by: NHannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

As tcp_rcv_state_process() has already calls tcp_mtup_init() for non-fastopen
sock, we can delete the redundant calls of tcp_mtup_init() in
tcp_{v4,v6}_syn_recv_sock().
Signed-off-by: NWeiping Pan <panweiping3@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Doesn't bring much, but also doesn't hurt us to fix 'em:

1) In tpacket_rcv() flush dcache page we can restirct the scope
   for start and end and remove one layer of indent.

2) In tpacket_destruct_skb() we can restirct the scope for ph.

3) In alloc_one_pg_vec_page() we can remove the NULL assignment
   and change spacing a bit.
Signed-off-by: NDaniel Borkmann <dborkman@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Since commit c5441932("GRE: Refactor GRE tunneling code")
introduced function ip_tunnel_hash(), the argument itn is no
longer in use, so remove it.
Signed-off-by: NDuan Jiong <duanj.fnst@cn.fujitsu.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NStephen Hemminger <stephen@networkplumber.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

softnet_data is already set to 0, no need to use memset or initialize
specific fields to 0 or NULL afterwards.
Signed-off-by: NSabrina Dubroca <sd@queasysnail.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Add a description to the vxlan module, helping save the world
from the minions of destruction and confusion.
Signed-off-by: NJesse Brandeburg <jesse.brandeburg@intel.com>
CC: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Shradha Shah says:

====================
Bug Fixes for SFC driver

I am taking over the upstream patch submission work for the
sfc driver from Ben Hutchings.

These patches are bug fixes to the sfc driver involving
replacement of the PORT RESET MC command and fixing transposed
ptp_{under,over}size_sync_window_statistics

The PORT_RESET bug fix is needed for all versions supporting EF10
i.e all versions including and after 3.12.
====================
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Somehow I transposed these two while bringing the original statistics
support upstream.

Fixes: 99691c4a ('sfc: Add PTP counters to ethtool stats')
Signed-off-by: NBen Hutchings <bhutchings@solarflare.com>
Signed-off-by: NShradha Shah <sshah@solarflare.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

PORT_RESET MC command was NOP in the ef10 firmware hence we are using
ENTITY_RESET to make sure all resource allocations are reset.
Signed-off-by: NShradha Shah <sshah@solarflare.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

So that we will not expose struct tcf_common to modules.

Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Cc: David S. Miller <davem@davemloft.net>
Signed-off-by: NCong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: NJamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Every action ops has a pointer to hash info, so we don't need to
hard-code it in each module.

Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Cc: David S. Miller <davem@davemloft.net>
Signed-off-by: NCong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: NJamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When timestamping is enabled, stmmac_tx_clean will call
stmmac_get_tx_hwtstamp to get tx TS.
But the skb can be NULL because the last of its tx_skbuff is NULL
if this packet frame is filled in more than one descriptors.

To fix the issue, change the code:
- Store TX skb to the tx_skbuff[] of frame's last segment.
- Check skb is not NULL in stmmac_get_tx_hwtstamp.
Signed-off-by: NBruce Liu <damuzi000@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The Allwinner A20 has an ethernet controller that seems to be
an early version of Synopsys DesignWare MAC 10/100/1000 Universal,
which is supported by the stmmac driver.

Allwinner's GMAC requires setting additional registers in the SoC's
clock control unit.

The exact version of the DWMAC IP that Allwinner uses is unknown,
thus the exact feature set is unknown.
Signed-off-by: NChen-Yu Tsai <wens@csie.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The stmmac driver core allows passing feature flags and callbacks via
platform data. Add a similar stmmac_of_data to pass flags and callbacks
tied to compatible strings. This allows us to extend stmmac with glue
layers for different SoCs.
Signed-off-by: NChen-Yu Tsai <wens@csie.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The snps,phy-addr device tree property is non-standard, and should be
removed in favor of proper phy node support. Remove it from the binding
documents and warn if the property is still used.

Most PHYs respond to address 0, but a few don't, so auto-detect PHY
address by default, to make up for the lack of explicit address selection.
Signed-off-by: NChen-Yu Tsai <wens@csie.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

"snps,force_sf_dma_mode" is documented in stmmac device tree bindings,
but is never handled by the driver.
Signed-off-by: NChen-Yu Tsai <wens@csie.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

stmmac callbacks have been extended for better separation.
Update them to avoid breakage.
Signed-off-by: NChen-Yu Tsai <wens@csie.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The current .init and .exit callbacks requires access to driver
private data structures. This is not a good seperation and abstraction.

Instead, we add a new .setup callback for allocating private data, and
pass the returned pointer to the other callbacks.
Signed-off-by: NChen-Yu Tsai <wens@csie.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The DWMAC has a reset assert line, which is used on some SoCs. Add an
optional reset control to stmmac driver core.

To support reset control deferred probing, this patch changes the driver
probe function to return the actual error, instead of just -EINVAL.
Signed-off-by: NChen-Yu Tsai <wens@csie.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The stmmac driver does not enable the main clock during the probe phase.
If the clock was not enabled by the boot loader or was disabled by the
kernel, hardware features and the MDIO bus would not be probed properly.
Signed-off-by: NChen-Yu Tsai <wens@csie.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Though described as required, the "phy-handle" property for the DaVinci EMAC
binding is actually optional, as the driver will happily function without it,
assuming 100/FULL link; the property is not specified  either in the example
device node,  or in the actual EMAC device nodes for DA850 and AM3517 device
trees.
Signed-off-by: NSergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When I create a new namespace with 'ip netns add net0', or add/remove
new links in a namespace with 'ip link add/delete type veth', rx/tx
queues events can be got in all namespaces. That is because rx/tx queue
ktypes do not have namespace support, and their kobj parents are setted to
NULL. This patch is to fix it.
Reported-by: NLibo Chen <chenlibo@huawei.com>
Signed-off-by: NLibo Chen <chenlibo@huawei.com>
Signed-off-by: NWeilong Chen <chenweilong@huawei.com>
Acked-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

It is not actually implemented.

Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Cc: David S. Miller <davem@davemloft.net>
Signed-off-by: NCong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

To silent "make htmldocs" warning.
Reported-by: Nkbuild test robot <fengguang.wu@intel.com>
Signed-off-by: NJason Wang <jasowang@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The commit 91705c61 ("net: sctp: trivial: update mailing list
address") updated almost all the SCTP mailing list address from

	"lksctp-developers@lists.sourceforge.net"
to
	"linux-sctp@vger.kernel.org"

except for the one in include/linux/sctp.h file. Fix this way trivial
one so that all is updated.
Signed-off-by: NJean Sacren <sakiwit@gmail.com>
Cc: Daniel Borkmann <dborkman@redhat.com>
Acked-by: NDaniel Borkmann <dborkman@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

ipv6_link_dev_addr sorts newly added addresses by scope in
ifp->addr_list. Smaller scope addresses are added to the tail of the
list. Use this fact to iterate in reverse over addr_list and break out
as soon as a higher scoped one showes up, so we can spare some cycles
on machines with lot's of addresses.

The ordering of the addresses is not relevant and we are more likely to
get the eui64 generated address with this change anyway.
Suggested-by: NBrian Haley <brian.haley@hp.com>
Signed-off-by: NHannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Code should avoid needless exports, don't export something unless it used.
Make local functions static and remove unused stubs.
Signed-off-by: NStephen Hemminger <stephen@networkplumber.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Previous patch changed prototypes, but forgot functions.
Signed-off-by: NFengguang Wu <fengguang.wu@intel.com>
Acked-by: NStephen Hemminger <stephen@networkplumber.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

We currently don't report IPV6_RECVPKTINFO in cmsg access ancillary data
for IPv4 datagrams on IPv6 sockets.

This patch splits the ip6_datagram_recv_ctl into two functions, one
which handles both protocol families, AF_INET and AF_INET6, while the
ip6_datagram_recv_specific_ctl only handles IPv6 cmsg data.

ip6_datagram_recv_*_ctl never reported back any errors, so we can make
them return void. Also provide a helper for protocols which don't offer dual
personality to further use ip6_datagram_recv_ctl, which is exported to
modules.

I needed to shuffle the code for ping around a bit to make it easier to
implement dual personality for ping ipv6 sockets in future.
Reported-by: NGert Doering <gert@space.net>
Signed-off-by: NHannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Replace some magic numbers which describe states of 4-state model
loss generator with enumerate.
Signed-off-by: NYang Yingliang <yangyingliang@huawei.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

With the introduction of IPV6_FL_F_REFLECT, there is no guarantee of
flow label unicity. This patch introduces a new sysctl to protect the old
behaviour, enable by default.

Changelog of V3:
 * rename ip6_flowlabel_consistency to flowlabel_consistency
 * use net_info_ratelimited()
 * checkpatch cleanups
Signed-off-by: NFlorent Fourcot <florent.fourcot@enst-bretagne.fr>
Acked-by: NHannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This information is already available via IPV6_FLOWINFO
of IPV6_2292PKTOPTIONS, and them a filtering to get the flow label
information. But it is probably logical and easier for users to add this
here, and to control both sent/received flow label values with the
IPV6_FLOWLABEL_MGR option.
Signed-off-by: NFlorent Fourcot <florent.fourcot@enst-bretagne.fr>
Acked-by: NHannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

With this option, the socket will reply with the flow label value read
on received packets.

The goal is to have a connection with the same flow label in both
direction of the communication.

Changelog of V4:
 * Do not erase the flow label on the listening socket. Use pktopts to
 store the received value
Signed-off-by: NFlorent Fourcot <florent.fourcot@enst-bretagne.fr>
Acked-by: NHannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>