Add constants and callback functions for the dwmac on rk3128 soc.
As can be seen, the base structure is the same, only registers
and the bits in them moved slightly.
Signed-off-by: NDavid Wu <david.wu@rock-chips.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Treat the ef/04/01 interface class/subclass/protocol combination used
by the Novatel Verizon USB730L (1410:9030) as a possible RNDIS
interface.

 T:  Bus=01 Lev=02 Prnt=02 Port=01 Cnt=02 Dev#= 17 Spd=480 MxCh= 0
 D:  Ver= 2.00 Cls=00(>ifc ) Sub=00 Prot=00 MxPS=64 #Cfgs=  3
 P:  Vendor=1410 ProdID=9030 Rev=03.10
 S:  Manufacturer=Novatel Wireless
 S:  Product=MiFi USB730L
 S:  SerialNumber=0123456789ABCDEF
 C:  #Ifs= 3 Cfg#= 1 Atr=80 MxPwr=500mA
 I:  If#= 0 Alt= 0 #EPs= 1 Cls=ef(misc ) Sub=04 Prot=01 Driver=rndis_host
 I:  If#= 1 Alt= 0 #EPs= 2 Cls=0a(data ) Sub=00 Prot=00 Driver=rndis_host
 I:  If#= 2 Alt= 0 #EPs= 1 Cls=03(HID  ) Sub=00 Prot=00 Driver=usbhid

Once the network interface is brought up, the user just needs to run a
DHCP client to get IP address and routing setup.

As a side note, other Novatel Verizon USB730L models with the same
vid:pid end up exposing a standard ECM interface which doesn't require
any other kernel update to make it work.
Signed-off-by: NAleksander Morgado <aleksander@aleksander.es>
Reviewed-by: NBjørn Mork <bjorn@mork.no>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When RTM_GETSTATS was added the fields of its header struct were not all
initialized when returning the result thus leaking 4 bytes of information
to user-space per rtnl_fill_statsinfo call, so initialize them now. Thanks
to Alexander Potapenko for the detailed report and bisection.
Reported-by: NAlexander Potapenko <glider@google.com>
Fixes: 10c9ead9 ("rtnetlink: add new RTM_GETSTATS message to dump link stats")
Signed-off-by: NNikolay Aleksandrov <nikolay@cumulusnetworks.com>
Acked-by: NRoopa Prabhu <roopa@cumulusnetworks.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Starting from linux-4.4, 3WHS no longer takes the listener lock.

Since this time, we might hit a use-after-free in sk_filter_charge(),
if the filter we got in the memcpy() of the listener content
just happened to be replaced by a thread changing listener BPF filter.

To fix this, we need to make sure the filter refcount is not already
zero before incrementing it again.

Fixes: e994b2f0 ("tcp: do not lock listener to process SYN packets")
Signed-off-by: NEric Dumazet <edumazet@google.com>
Acked-by: NAlexei Starovoitov <ast@kernel.org>
Acked-by: NDaniel Borkmann <daniel@iogearbox.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Jiri Pirko says:

====================
mlxsw: Fixes in GRE offloading

Petr says:

This patchset fixes a couple unrelated problems in offloading IP-in-IP tunnels
in mlxsw driver.

- The first patch fixes a potential reference-counting problem that might lead
  to a kernel crash.

- The second patch associates IPIP next hops with their loopback RIFs. Besides
  being the right thing to do, it also fixes a problem where offloaded IPv6
  routes that forward to IP-in-IP netdevices were not flagged as such.
====================
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When considering whether to set RTNH_F_OFFLOAD flag on an IPv6 route,
mlxsw_sp_fib6_entry_offload_set() looks up the mlxsw_sp_nexthop
corresponding to a given route, and decides based on whether the next
hop's offloaded flag was set. When looking for the matching next hop, it
also takes into account the device of the route, which must match next
hop's RIF.

IPIP next hops however hitherto didn't set the RIF. As a result, IPv6
routes forwarding traffic to IP-in-IP netdevices are never marked as
offloaded, even when they actually are.

Thus track RIF of IPIP next hops the same way as that of ETHERNET next
hops.

Fixes: 8f28a309 ("mlxsw: spectrum_router: Support IPv6 overlay encap")
Signed-off-by: NPetr Machata <petrm@mellanox.com>
Reviewed-by: NIdo Schimmel <idosch@mellanox.com>
Signed-off-by: NJiri Pirko <jiri@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When creating a new RIF, bumping RIF count of the containing VR is the
last thing to be done. Symmetrically, when destroying a RIF, RIF count
is first dropped and only then the rest of the cleanup proceeds.

That's a problem for loopback RIFs. Those hold two VR references: one
for overlay and one for underlay. mlxsw_sp_rif_destroy() releases the
overlay one, and the deconfigure() callback the underlay one. But if
both overlay and underlay are the same, and if there are no other
artifacts holding the VR alive, this put actually destroys the VR. Later
on, when mlxsw_sp_rif_destroy() calls mlxsw_sp_vr_put() for the same VR,
the VR will already have been released and the kernel crashes with NULL
pointer dereference.

The underlying problem is that the RIF under destruction ends up
referencing the overlay VR much longer than it claims: all the way until
the call to mlxsw_sp_vr_put(). So line up the reference counting
properly to reflect this. Make corresponding changes in
mlxsw_sp_rif_create() as well for symmetry.

Fixes: 6ddb7426 ("mlxsw: spectrum_router: Introduce loopback RIFs")
Signed-off-by: NPetr Machata <petrm@mellanox.com>
Reviewed-by: NIdo Schimmel <idosch@mellanox.com>
Signed-off-by: NJiri Pirko <jiri@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

If this sanity check fails, we must free 'rss_indir'. Otherwise there is a
memory leak.
'goto err' as done in the other error handling paths to fix it.

Fixes: 46a3df9f ("net: hns3: Fix for setting rss_size incorrectly")
Signed-off-by: NChristophe JAILLET <christophe.jaillet@wanadoo.fr>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

On Armada 7K/8K we need to explicitly enable the bus clock. The bus clock
is optional because not all the SoCs need them but at least for Armada
7K/8K it is actually mandatory.

The binding documentation is updating accordingly.
Signed-off-by: NGregory CLEMENT <gregory.clement@free-electrons.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This linksys dongle by default comes up in cdc_ether mode.
This patch allows r8152 to claim the device:
   Bus 002 Device 002: ID 13b1:0041 Linksys
Signed-off-by: NGrant Grundler <grundler@chromium.org>
Reviewed-by: NDouglas Anderson <dianders@chromium.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The l2tp_eth module crashes if its netlink callbacks are run when the
pernet data aren't initialised.

We should normally register_pernet_device() before the genl callbacks.
However, the pernet data only maintain a list of l2tpeth interfaces,
and this list is never used. So let's just drop pernet handling
instead.

Fixes: d9e31d17 ("l2tp: Add L2TP ethernet pseudowire support")
Signed-off-by: NGuillaume Nault <g.nault@alphalink.fr>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Xin Long says:

====================
ip_gre: a bunch of fixes for erspan

This patchset is to fix some issues that could cause 0 or low
performance, and even unexpected truncated packets on erspan.
====================
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The patch 'ip_gre: ipgre_tap device should keep dst' fixed
the issue ipgre_tap dev mtu couldn't be updated in tx path.

The same fix is needed for erspan as well.

Fixes: 84e54fe0 ("gre: introduce native tunnel support for ERSPAN")
Signed-off-by: NXin Long <lucien.xin@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

According to __gre_tunnel_init, tunnel->hlen should be set as the
headers' length between inner packet and outer iphdr.

It would be used especially to calculate a proper mtu when updating
mtu in tnl_update_pmtu. Now without setting it, a bigger mtu value
than expected would be updated, which hurts performance a lot.

This patch is to fix it by setting tunnel->hlen with:
   tunnel->tun_hlen + tunnel->encap_hlen + sizeof(struct erspanhdr)

Fixes: 84e54fe0 ("gre: introduce native tunnel support for ERSPAN")
Signed-off-by: NXin Long <lucien.xin@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

As a ARPHRD_ETHER device, skb->len in erspan_xmit is the length
of the whole ether packet. So before checking if a packet size
exceeds the mtu, skb->len should subtract dev->hard_header_len.

Otherwise, all packets with max size according to mtu would be
trimmed to be truncated packet.

Fixes: 84e54fe0 ("gre: introduce native tunnel support for ERSPAN")
Signed-off-by: NXin Long <lucien.xin@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

erspan only uses the first 10 bits of session_id as the key to look
up the tunnel. But in erspan_rcv, it missed 'session_id & ID_MASK'
when getting the key from session_id.

If any other flag is also set in session_id in a packet, it would
fail to find the tunnel due to incorrect key in erspan_rcv.

This patch is to add 'session_id & ID_MASK' there and also remove
the unnecessary variable session_id.

Fixes: 84e54fe0 ("gre: introduce native tunnel support for ERSPAN")
Signed-off-by: NXin Long <lucien.xin@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

In commit e3a77561 ("tipc: split up function tipc_msg_eval()"),
we have updated the function tipc_msg_lookup_dest() to set the error
codes to negative values at destination lookup failures. Thus when
the function sets the error code to -TIPC_ERR_NO_NAME, its inserted
into the 4 bit error field of the message header as 0xf instead of
TIPC_ERR_NO_NAME (1). The value 0xf is an unknown error code.

In this commit, we set only positive error code.

Fixes: e3a77561 ("tipc: split up function tipc_msg_eval()")
Signed-off-by: NParthasarathy Bhuvaragan <parthasarathy.bhuvaragan@ericsson.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Move sparse annotation right after pointer type.

Fixes sparse warning:
    drivers/net/ppp/ppp_generic.c:1422:13: warning: incorrect type in initializer (different address spaces)
    drivers/net/ppp/ppp_generic.c:1422:13:    expected void const [noderef] <asn:3>*__vpp_verify
    drivers/net/ppp/ppp_generic.c:1422:13:    got int *<noident>
    ...

Fixes: e5dadc65 ("ppp: Fix false xmit recursion detect with two ppp devices")
Signed-off-by: NGuillaume Nault <g.nault@alphalink.fr>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Paolo Abeni says:

====================
udp: fix early demux for mcast packets

Currently the early demux callbacks do not perform source address validation.
This is not an issue for TCP or UDP unicast, where the early demux
is only allowed for connected sockets and the source address is validated
for the first packet and never change.

The UDP protocol currently allows early demux also for unconnected multicast
sockets, and we are not currently doing any validation for them, after that
the first packet lands on the socket: beyond ignoring the rp_filter - if
enabled - any kind of martian sources are also allowed.

This series addresses the issue allowing the early demux callback to return an
error code, and performing the proper checks for unconnected UDP multicast
sockets before leveraging the rx dst cache.

Alternatively we could disable the early demux for unconnected mcast sockets,
but that would cause relevant performance regression - around 50% - while with
this series, with full rp_filter in place, we keep the regression to a more
moderate level.
====================
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The UDP early demux can leverate the rx dst cache even for
multicast unconnected sockets.

In such scenario the ipv4 source address is validated only on
the first packet in the given flow. After that, when we fetch
the dst entry  from the socket rx cache, we stop enforcing
the rp_filter and we even start accepting any kind of martian
addresses.

Disabling the dst cache for unconnected multicast socket will
cause large performace regression, nearly reducing by half the
max ingress tput.

Instead we factor out a route helper to completely validate an
skb source address for multicast packets and we call it from
the UDP early demux for mcast packets landing on unconnected
sockets, after successful fetching the related cached dst entry.

This still gives a measurable, but limited performance
regression:

		rp_filter = 0		rp_filter = 1
edmux disabled:	1182 Kpps		1127 Kpps
edmux before:	2238 Kpps		2238 Kpps
edmux after:	2037 Kpps		2019 Kpps

The above figures are on top of current net tree.
Applying the net-next commit 6e617de8 ("net: avoid a full
fib lookup when rp_filter is disabled.") the delta with
rp_filter == 0 will decrease even more.

Fixes: 421b3885 ("udp: ipv4: Add udp early demux")
Signed-off-by: NPaolo Abeni <pabeni@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Currently no error is emitted, but this infrastructure will
used by the next patch to allow source address validation
for mcast sockets.
Since early demux can do a route lookup and an ipv4 route
lookup can return an error code this is consistent with the
current ipv4 route infrastructure.
Signed-off-by: NPaolo Abeni <pabeni@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Now when updating mtu in tx path, it doesn't consider ARPHRD_ETHER tunnel
device, like ip6gre_tap tunnel, for which it should also subtract ether
header to get the correct mtu.
Signed-off-by: NXin Long <lucien.xin@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The patch 'ip_gre: ipgre_tap device should keep dst' fixed
a issue that ipgre_tap mtu couldn't be updated in tx path.

The same fix is needed for ip6gre_tap as well.
Signed-off-by: NXin Long <lucien.xin@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Without keeping dst, the tunnel will not update any mtu/pmtu info,
since it does not have a dst on the skb.

Reproducer:
  client(ipgre_tap1 - eth1) <-----> (eth1 - ipgre_tap1)server

After reducing eth1's mtu on client, then perforamnce became 0.

This patch is to netif_keep_dst in gre_tap_init, as ipgre does.
Reported-by: NJianlin Shi <jishi@redhat.com>
Signed-off-by: NXin Long <lucien.xin@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Drivers that use the start method for netlink dumping rely on dumpit not
being called if start fails. For example, ila_xlat.c allocates memory
and assigns it to cb->args[0] in its start() function. It might fail to
do that and return -ENOMEM instead. However, even when returning an
error, dumpit will be called, which, in the example above, quickly
dereferences the memory in cb->args[0], which will OOPS the kernel. This
is but one example of how this goes wrong.

Since start() has always been a function with an int return type, it
therefore makes sense to use it properly, rather than ignoring it. This
patch thus returns early and does not call dumpit() when start() fails.
Signed-off-by: NJason A. Donenfeld <Jason@zx2c4.com>
Cc: Johannes Berg <johannes@sipsolutions.net>
Reviewed-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Saeed Mahameed says:

====================
mlx5-fixes-2017-09-28

Misc. fixes for mlx5 drivers.
====================
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

sk->sk_prot and sk->sk_prot_creator can differ when the app uses
IPV6_ADDRFORM (transforming an IPv6-socket to an IPv4-one).
Which is why sk_prot_creator is there to make sure that sk_prot_free()
does the kmem_cache_free() on the right kmem_cache slab.

Now, if such a socket gets transformed back to a listening socket (using
connect() with AF_UNSPEC) we will allocate an IPv4 tcp_sock through
sk_clone_lock() when a new connection comes in. But sk_prot_creator will
still point to the IPv6 kmem_cache (as everything got copied in
sk_clone_lock()). When freeing, we will thus put this
memory back into the IPv6 kmem_cache although it was allocated in the
IPv4 cache. I have seen memory corruption happening because of this.

With slub-debugging and MEMCG_KMEM enabled this gives the warning
	"cache_from_obj: Wrong slab cache. TCPv6 but object is from TCP"

A C-program to trigger this:

void main(void)
{
        int fd = socket(AF_INET6, SOCK_STREAM, IPPROTO_TCP);
        int new_fd, newest_fd, client_fd;
        struct sockaddr_in6 bind_addr;
        struct sockaddr_in bind_addr4, client_addr1, client_addr2;
        struct sockaddr unsp;
        int val;

        memset(&bind_addr, 0, sizeof(bind_addr));
        bind_addr.sin6_family = AF_INET6;
        bind_addr.sin6_port = ntohs(42424);

        memset(&client_addr1, 0, sizeof(client_addr1));
        client_addr1.sin_family = AF_INET;
        client_addr1.sin_port = ntohs(42424);
        client_addr1.sin_addr.s_addr = inet_addr("127.0.0.1");

        memset(&client_addr2, 0, sizeof(client_addr2));
        client_addr2.sin_family = AF_INET;
        client_addr2.sin_port = ntohs(42421);
        client_addr2.sin_addr.s_addr = inet_addr("127.0.0.1");

        memset(&unsp, 0, sizeof(unsp));
        unsp.sa_family = AF_UNSPEC;

        bind(fd, (struct sockaddr *)&bind_addr, sizeof(bind_addr));

        listen(fd, 5);

        client_fd = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);
        connect(client_fd, (struct sockaddr *)&client_addr1, sizeof(client_addr1));
        new_fd = accept(fd, NULL, NULL);
        close(fd);

        val = AF_INET;
        setsockopt(new_fd, SOL_IPV6, IPV6_ADDRFORM, &val, sizeof(val));

        connect(new_fd, &unsp, sizeof(unsp));

        memset(&bind_addr4, 0, sizeof(bind_addr4));
        bind_addr4.sin_family = AF_INET;
        bind_addr4.sin_port = ntohs(42421);
        bind(new_fd, (struct sockaddr *)&bind_addr4, sizeof(bind_addr4));

        listen(new_fd, 5);

        client_fd = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);
        connect(client_fd, (struct sockaddr *)&client_addr2, sizeof(client_addr2));

        newest_fd = accept(new_fd, NULL, NULL);
        close(new_fd);

        close(client_fd);
        close(new_fd);
}

As far as I can see, this bug has been there since the beginning of the
git-days.
Signed-off-by: NChristoph Paasch <cpaasch@apple.com>
Reviewed-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

mv88e6xxx_g2_irq_free locks the registers mutex, but not
mv88e6xxx_g1_irq_free, which results in a stack trace from
assert_reg_lock when unloading the mv88e6xxx module. Fix this.

Fixes: 3460a577 ("net: dsa: mv88e6xxx: Mask g1 interrupts and free interrupt")
Signed-off-by: NVivien Didelot <vivien.didelot@savoirfairelinux.com>
Reviewed-by: NFlorian Fainelli <f.fainelli@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Packet socket option po->has_vnet_hdr can be updated concurrently with
other operations if no ring is attached.

Do not test the option twice in packet_snd, as the value may change in
between calls. A race on setsockopt disable may cause a packet > mtu
to be sent without having GSO options set.

Fixes: bfd5f4a3 ("packet: Add GSO/csum offload support.")
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>

Once a socket has po->fanout set, it remains a member of the group
until it is destroyed. The prot_hook must be constant and identical
across sockets in the group.

If fanout_add races with packet_do_bind between the test of po->fanout
and taking the lock, the bind call may make type or dev inconsistent
with that of the fanout group.

Hold po->bind_lock when testing po->fanout to avoid this race.

I had to introduce artificial delay (local_bh_enable) to actually
observe the race.

Fixes: dc99f600 ("packet: Add fanout support.")
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>

Re-enable the MAC receiver by setting CONFIG_RE before powering down,
as instructed in section 6.3.5.1 of [1].  Without this the MAC fails
to receive WoL packets and never wakes up.

[1] DWC Ethernet QoS Databook 4.10a October 2014
Signed-off-by: NEd Blake <ed.blake@sondrel.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Add hook to stmmac_pltfr_pm_ops for suspend / resume handling.
Signed-off-by: NEd Blake <ed.blake@sondrel.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

We cannot be registering the network device first, then setting its
carrier off and finally connecting it to a PHY, doing that leaves a
window during which the carrier is at best inconsistent, and at worse
the device is not usable without a down/up sequence since the network
device is visible to user space with possibly no PHY device attached.

Re-order steps so that they make logical sense. This fixes some devices
where the port was not usable after e.g: an unbind then bind of the
driver.

Fixes: 0071f56e ("dsa: Register netdev before phy")
Fixes: 91da11f8 ("net: Distributed Switch Architecture protocol support")
Signed-off-by: NFlorian Fainelli <f.fainelli@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Ports with the same VLAN must all be in the same bridge. However the
CPU and DSA ports need to be in multiple VLANs spread over multiple
bridges. So exclude them when performing this test.

Fixes: b2f81d30 ("net: dsa: add CPU and DSA ports as VLAN members")
Signed-off-by: NAndrew Lunn <andrew@lunn.ch>
Reviewed-by: NVivien Didelot <vivien.didelot@savoirfairelinux.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

My prior fix was not complete, as we were dereferencing a pointer
three times per node, not twice as I initially thought.

Fixes: 4cc5b44b ("inetpeer: fix RCU lookup()")
Fixes: b145425f ("inetpeer: remove AVL implementation in favor of RB tree")
Signed-off-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Antoine Tenart says:

====================
net: mvpp2: various fixes

This series contains 3 fixes for the Marvell PPv2 driver.

Since v1:
  - Removed one patch about dma masks as it would need a better fix.
  - Added one fix about the MAC Tx clock source selection.
====================
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch stops the internal MAC Tx clock from being enabled as the
internal clock isn't used. The definition used for the bit controlling
this behaviour is renamed as well as it was wrongly named (bit 4 of
GMAC_CTRL_2_REG).

Fixes: 3919357f ("net: mvpp2: initialize the GMAC when using a port")
Signed-off-by: NAntoine Tenart <antoine.tenart@free-electrons.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The private port_list array has a list of pointers to mvpp2_port
instances. This list is allocated given the number of ports enabled in
the device tree, but the pointers are set using the port-id property. If
on a single port is enabled, the port_list array will be of size 1, but
when registering the port, if its id is not 0 the driver will crash.
Other crashes were encountered in various situations.

This fixes the issue by using an index not equal to the value of the
port-id property.

Fixes: 3f518509 ("ethernet: Add new driver for Marvell Armada 375 network unit")
Signed-off-by: NAntoine Tenart <antoine.tenart@free-electrons.com>
Signed-off-by: NYan Markman <ymarkman@marvell.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Parsing fragmentation detection failed due to wrong configured
parser TCAM entry's. Some traffic was marked as fragmented in RX
descriptor, even it wasn't IP fragmented. The hardware also failed to
calculate checksums which lead to use software checksum and caused
performance degradation.

Fixes: 3f518509 ("ethernet: Add new driver for Marvell Armada 375 network unit")
Signed-off-by: NAntoine Tenart <antoine.tenart@free-electrons.com>
Signed-off-by: NStefan Chulski <stefanc@marvell.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

KMSAN (https://github.com/google/kmsan) reported accessing uninitialized
skb->data[0] in the case the skb is empty (i.e. skb->len is 0):

================================================
BUG: KMSAN: use of uninitialized memory in tun_get_user+0x19ba/0x3770
CPU: 0 PID: 3051 Comm: probe Not tainted 4.13.0+ #3140
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011
Call Trace:
...
 __msan_warning_32+0x66/0xb0 mm/kmsan/kmsan_instr.c:477
 tun_get_user+0x19ba/0x3770 drivers/net/tun.c:1301
 tun_chr_write_iter+0x19f/0x300 drivers/net/tun.c:1365
 call_write_iter ./include/linux/fs.h:1743
 new_sync_write fs/read_write.c:457
 __vfs_write+0x6c3/0x7f0 fs/read_write.c:470
 vfs_write+0x3e4/0x770 fs/read_write.c:518
 SYSC_write+0x12f/0x2b0 fs/read_write.c:565
 SyS_write+0x55/0x80 fs/read_write.c:557
 do_syscall_64+0x242/0x330 arch/x86/entry/common.c:284
 entry_SYSCALL64_slow_path+0x25/0x25 arch/x86/entry/entry_64.S:245
...
origin:
...
 kmsan_poison_shadow+0x6e/0xc0 mm/kmsan/kmsan.c:211
 slab_alloc_node mm/slub.c:2732
 __kmalloc_node_track_caller+0x351/0x370 mm/slub.c:4351
 __kmalloc_reserve net/core/skbuff.c:138
 __alloc_skb+0x26a/0x810 net/core/skbuff.c:231
 alloc_skb ./include/linux/skbuff.h:903
 alloc_skb_with_frags+0x1d7/0xc80 net/core/skbuff.c:4756
 sock_alloc_send_pskb+0xabf/0xfe0 net/core/sock.c:2037
 tun_alloc_skb drivers/net/tun.c:1144
 tun_get_user+0x9a8/0x3770 drivers/net/tun.c:1274
 tun_chr_write_iter+0x19f/0x300 drivers/net/tun.c:1365
 call_write_iter ./include/linux/fs.h:1743
 new_sync_write fs/read_write.c:457
 __vfs_write+0x6c3/0x7f0 fs/read_write.c:470
 vfs_write+0x3e4/0x770 fs/read_write.c:518
 SYSC_write+0x12f/0x2b0 fs/read_write.c:565
 SyS_write+0x55/0x80 fs/read_write.c:557
 do_syscall_64+0x242/0x330 arch/x86/entry/common.c:284
 return_from_SYSCALL_64+0x0/0x6a arch/x86/entry/entry_64.S:245
================================================

Make sure tun_get_user() doesn't touch skb->data[0] unless there is
actual data.

C reproducer below:
==========================
    // autogenerated by syzkaller (http://github.com/google/syzkaller)

    #define _GNU_SOURCE

    #include <fcntl.h>
    #include <linux/if_tun.h>
    #include <netinet/ip.h>
    #include <net/if.h>
    #include <string.h>
    #include <sys/ioctl.h>

    int main()
    {
      int sock = socket(PF_INET, SOCK_STREAM, IPPROTO_IP);
      int tun_fd = open("/dev/net/tun", O_RDWR);
      struct ifreq req;
      memset(&req, 0, sizeof(struct ifreq));
      strcpy((char*)&req.ifr_name, "gre0");
      req.ifr_flags = IFF_UP | IFF_MULTICAST;
      ioctl(tun_fd, TUNSETIFF, &req);
      ioctl(sock, SIOCSIFFLAGS, "gre0");
      write(tun_fd, "hi", 0);
      return 0;
    }
==========================
Signed-off-by: NAlexander Potapenko <glider@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>