On unsuccesful ip6_datagram_connect(), if the failure is caused by
ip6_datagram_dst_update(), the sk peer information are cleared, but
the sk->sk_state is preserved.

If the socket was already in an established status, the overall sk
status is inconsistent and fouls later checks in datagram code.

Fix this saving the old peer information and restoring them in
case of failure. This also aligns ipv6 datagram connect() behavior
with ipv4.

v1 -> v2:
 - added missing Fixes tag

Fixes: 85cb73ff ("net: ipv6: reset daddr and dport in sk if connect() fails")
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Pablo Neira Ayuso says:

====================
Netfilter fixes for net

The following patchset contains Netfilter fixes for your net tree, they are:

1) Fixed hashtable representation doesn't support timeout flag, skip it
   otherwise rules to add elements from the packet fail bogusly fail with
   EOPNOTSUPP.

2) Fix bogus error with 32-bits ebtables userspace and 64-bits kernel,
   patch from Florian Westphal.

3) Sanitize proc names in several x_tables extensions, also from Florian.

4) Add sanitization to ebt_among wormhash logic, from Florian.

5) Missing release of hook array in flowtable.
====================

Merge tag 'linux-can-fixes-for-4.16-20180312' of ssh://gitolite.kernel.org/pub/scm/linux/kernel/git/mkl/linux-can

Marc Kleine-Budde says:

====================
pull-request: can 2018-03-12

this is a pull reqeust of 6 patches for net/master.

The first patch is by Wolfram Sang and fixes a bitshift vs. comparison mistake
in the m_can driver. Two patches of Marek Vasut repair the error handling in
the ifi driver. The two patches by Stephane Grosjean fix a "echo_skb is
occupied!" bug in the peak/pcie_fd driver. Bich HEMON's patch adds pinctrl
select state calls to the m_can's driver to further improve power saving during
suspend.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

Now when using 'ss' in iproute, kernel would try to load all _diag
modules, which also causes corresponding family and proto modules
to be loaded as well due to module dependencies.

Like after running 'ss', sctp, dccp, af_packet (if it works as a module)
would be loaded.

For example:

  $ lsmod|grep sctp
  $ ss
  $ lsmod|grep sctp
  sctp_diag              16384  0
  sctp                  323584  5 sctp_diag
  inet_diag              24576  4 raw_diag,tcp_diag,sctp_diag,udp_diag
  libcrc32c              16384  3 nf_conntrack,nf_nat,sctp

As these family and proto modules are loaded unintentionally, it
could cause some problems, like:

- Some debug tools use 'ss' to collect the socket info, which loads all
  those diag and family and protocol modules. It's noisy for identifying
  issues.

- Users usually expect to drop sctp init packet silently when they
  have no sense of sctp protocol instead of sending abort back.

- It wastes resources (especially with multiple netns), and SCTP module
  can't be unloaded once it's loaded.

...

In short, it's really inappropriate to have these family and proto
modules loaded unexpectedly when just doing debugging with inet_diag.

This patch is to introduce sock_load_diag_module() where it loads
the _diag module only when it's corresponding family or proto has
been already registered.

Note that we can't just load _diag module without the family or
proto loaded, as some symbols used in _diag module are from the
family or proto module.

v1->v2:
  - move inet proto check to inet_diag to avoid a compiling err.
v2->v3:
  - define sock_load_diag_module in sock.c and export one symbol
    only.
  - improve the changelog.
Reported-by: Sabrina Dubroca <sd@queasysnail.net>
Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Acked-by: Phil Sutter <phil@nwl.cc>
Acked-by: Sabrina Dubroca <sd@queasysnail.net>
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Michael Chan says:

====================
bnxt_en: Bug fixes.

There are 3 bug fixes in this series to fix regressions recently
introduced when adding the new ring reservations scheme.  2 minor
fixes in the TC Flower code to return standard errno values and
to elide some unnecessary warning dmesg.  One Fixes the VLAN TCI
value passed to the stack by including the entire 16-bit VLAN TCI,
and the last fix is to check for valid VNIC ID before setting up or
shutting down LRO/GRO.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

During initialization, if we encounter errors, there is a code path that
calls bnxt_hwrm_vnic_set_tpa() with invalid VNIC ID.  This may cause a
warning in firmware logs.

Fixes: c0c050c5 ("bnxt_en: New Broadcom ethernet driver.")
Signed-off-by: Michael Chan <michael.chan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

bnxt_restore_pf_fw_resources routine frees PF resources by calling
close_nic and allocates the resources back, by doing open_nic. However,
this is not needed, if the PF is already in closed state.

This bug causes the driver to call open the device and call request_irq()
when it is not needed.  Ultimately, pci_disable_msix() will crash
when bnxt_en is unloaded.

This patch fixes the problem by skipping __bnxt_close_nic and
__bnxt_open_nic inside bnxt_restore_pf_fw_resources routine, if the
interface is not running.

Fixes: 80fcaf46 ("bnxt_en: Restore MSIX after disabling SRIOV.")
Signed-off-by: Venkat Duvvuru <venkatkumar.duvvuru@broadcom.com>
Signed-off-by: Michael Chan <michael.chan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Currently, internal error value is returned by the driver, when
hwrm_cfa_flow_alloc() fails due lack of resources.  We should be returning
Linux errno value -ENOSPC instead.

This patch also converts other similar command errors to standard Linux errno
code (-EIO) in bnxt_tc.c

Fixes: db1d36a2 ("bnxt_en: add TC flower offload flow_alloc/free FW cmds")
Signed-off-by: Venkat Duvvuru <venkatkumar.duvvuru@broadcom.com>
Signed-off-by: Michael Chan <michael.chan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Recent changes added the bnxt_init_int_mode() call in the driver's open
path whenever ring reservations are changed.  This call was previously
only called in the probe path.  In the open path, if MQPRIO TC has been
setup, the bnxt_init_int_mode() call would reset and mess up the MQPRIO
per TC rings.

Fix it by not re-initilizing bp->tx_nr_rings_per_tc in
bnxt_init_int_mode().  Instead, initialize it in the probe path only
after the bnxt_init_int_mode() call.

Fixes: 674f50a5 ("bnxt_en: Implement new method to reserve rings.")
Signed-off-by: Michael Chan <michael.chan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

When receiving a packet with VLAN tag, pass the entire 16-bit TCI to the
stack when calling __vlan_hwaccel_put_tag().  The current code is only
passing the 12-bit tag and it is missing the priority bits.
Signed-off-by: Michael Chan <michael.chan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

In some conditions when the driver fails to add a flow in HW and returns
an error back to the stack, the stack continues to invoke get_flow_stats()
and/or del_flow() on it. The driver fails these APIs with an error message
"no flow_node for cookie". The message gets logged repeatedly as long as
the stack keeps invoking these functions.

Fix this by removing the corresponding netdev_info() calls from these
functions.

Fixes: d7bc7305 ("bnxt_en: add code to query TC flower offload stats")
Signed-off-by: Sriharsha Basavapatna <sriharsha.basavapatna@broadcom.com>
Signed-off-by: Michael Chan <michael.chan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

The number of vnics to check must be determined ahead of time because
only standard RX rings require vnics to support RFS.  The logic is
similar to the ring reservation logic and we can now use the
refactored common functions to do most of the work in setting up
the firmware message.

Fixes: 8f23d638 ("bnxt_en: Expand bnxt_check_rings() to check all resources.")
Signed-off-by: Eddie Wai <eddie.wai@broadcom.com>
Signed-off-by: Michael Chan <michael.chan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

The bnxt_hwrm_reserve_{pf|vf}_rings() functions are very similar to
the bnxt_hwrm_check_{pf|vf}_rings() functions.  Refactor the former
so that the latter can make use of common code in the next patch.
Signed-off-by: Michael Chan <michael.chan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

In 664fcf12 (net: phy: Threaded interrupts allow some simplification)
the phy_interrupt system was changed to use a traditional threaded
interrupt scheme instead of a workqueue approach.

With this change, the phy status check moved into phy_change, which
did not report back to the caller whether or not the interrupt was
handled. This means that, in the case of a shared phy interrupt,
only the first phydev's interrupt registers are checked (since
phy_interrupt() would always return IRQ_HANDLED). This leads to
interrupt storms when it is a secondary device that's actually the
interrupt source.
Signed-off-by: Brad Mouring <brad.mouring@ni.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Make sure to apply the correct pin state in suspend/resume callbacks.
Putting pins in sleep state saves power.
Signed-off-by: Bich Hemon <bich.hemon@st.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

When an interface starts, the echo_skb array is empty and the network
queue should be started only. This patch replaces useless code and locks
when the internal RX_BARRIER message is received from the IP core, telling
the driver that tx may start.
Signed-off-by: Stephane Grosjean <s.grosjean@peak-system.com>
Cc: linux-stable <stable@vger.kernel.org>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

This patch makes atomic the handling of the linux-can echo_skb array and
the network tx queue. This prevents from the "BUG! echo_skb is occupied!"
message to be printed by the linux-can core, in SMP environments.
Reported-by: Diana Burgess <diana@peloton-tech.com>
Signed-off-by: Stephane Grosjean <s.grosjean@peak-system.com>
Cc: linux-stable <stable@vger.kernel.org>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

The new version of the IFI CANFD core has significantly less complex
error state indication logic. In particular, the warning/error state
bits are no longer all over the place, but are all present in the
STATUS register. Moreover, there is a new IRQ register bit indicating
transition between error states (active/warning/passive/busoff).

This patch makes use of this bit to weed out the obscure selective
INTERRUPT register clearing, which was used to carry over the error
state indication into the poll function. While at it, this patch
fixes the handling of the ACTIVE state, since the hardware provides
indication of the core being in ACTIVE state and that in turn fixes
the state transition indication toward userspace. Finally, register
reads in the poll function are moved to the matching subfunctions
since those are also no longer needed in the poll function.
Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Heiko Schocher <hs@denx.de>
Cc: Markus Marb <markus@marb.org>
Cc: Marc Kleine-Budde <mkl@pengutronix.de>
Cc: linux-stable <stable@vger.kernel.org>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

Older versions of the core are not compatible with the driver due
to various intrusive fixes of the core. Read out the VER register,
check the core revision bitfield and verify if the core in use is
new enough (rev 2.1 or newer) to work correctly with this driver.
Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Heiko Schocher <hs@denx.de>
Cc: Markus Marb <markus@marb.org>
Cc: Marc Kleine-Budde <mkl@pengutronix.de>
Cc: linux-stable <stable@vger.kernel.org>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

Due to a typo, the mask was destroyed by a comparison instead of a bit
shift.
Reported-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

Max delat_t should be the full_bucket/rate instead of the full_bucket.
Also report EINVAL if the rate is zero.

Fixes: 96fbc13d ("openvswitch: Add meter infrastructure")
Cc: Andy Zhou <azhou@ovn.org>
Signed-off-by: zhangliping <zhangliping02@baidu.com>
Acked-by: Pravin B Shelar <pshelar@ovn.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

Adding a macvlan device on top of a lowerdev that supports
the xfrm offloads fails with a new regression:
  # ip link add link ens1f0 mv0 type macvlan
  RTNETLINK answers: Operation not permitted

Tracing down the failure shows that the macvlan device inherits
the NETIF_F_HW_ESP and NETIF_F_HW_ESP_TX_CSUM feature flags
from the lowerdev, but with no dev->xfrmdev_ops API filled
in, it doesn't actually support xfrm.  When the request is
made to add the new macvlan device, the XFRM listener for
NETDEV_REGISTER calls xfrm_api_check() which fails the new
registration because dev->xfrmdev_ops is NULL.

The macvlan creation succeeds when we filter out the ESP
feature flags in macvlan_fix_features(), so let's filter them
out like we're already filtering out ~NETIF_F_NETNS_LOCAL.
When XFRM support is added in the future, we can add the flags
into MACVLAN_FEATURES.

This same problem could crop up in the future with any other
new feature flags, so let's filter out any flags that aren't
defined as supported in macvlan.

Fixes: d77e38e6 ("xfrm: Add an IPsec hardware offloading API")
Reported-by: Alexey Kodanev <alexey.kodanev@oracle.com>
Signed-off-by: Shannon Nelson <shannon.nelson@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Otherwise we leak this array.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

ebt_among is special, it has a dynamic match size and is exempt
from the central size checks.

commit c4585a28 ("bridge: ebt_among: add missing match size checks")
added validation for pool size, but missed fact that the macros
ebt_among_wh_src/dst can already return out-of-bound result because
they do not check value of wh_src/dst_ofs (an offset) vs. the size
of the match that userspace gave to us.

v2:
check that offset has correct alignment.
Paolo Abeni points out that we should also check that src/dst
wormhash arrays do not overlap, and src + length lines up with
start of dst (or vice versa).
v3: compact wormhash_sizes_valid() part

NB: Fixes tag is intentionally wrong, this bug exists from day
one when match was added for 2.6 kernel. Tag is there so stable
maintainers will notice this one too.

Tested with same rules from the earlier patch.

Fixes: c4585a28 ("bridge: ebt_among: add missing match size checks")
Reported-by: <syzbot+bdabab6f1983a03fc009@syzkaller.appspotmail.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

recent and hashlimit both create /proc files, but only check that
name is 0 terminated.

This can trigger WARN() from procfs when name is "" or "/".
Add helper for this and then use it for both.

Cc: Eric Dumazet <eric.dumazet@gmail.com>
Reported-by: Eric Dumazet <eric.dumazet@gmail.com>
Reported-by: <syzbot+0502b00edac2a0680b61@syzkaller.appspotmail.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

The last rule in the blob has next_entry offset that is same as total size.
This made "ebtables32 -A OUTPUT -d de:ad:be:ef:01:02" fail on 64 bit kernel.

Fixes: b7181216 ("netfilter: ebtables: CONFIG_COMPAT: don't trust userland offsets")
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

William Tu says:

====================
a couple of erspan fixes

The series fixes a couple of erspan issues.
The first patch adds the erspan v2 proto type to the ip6 tunnel lookup.
The second patch improves the error handling when users screws the
version number in metadata.  The final patch makes sure the skb has
enough headroom for pushing erspan header when xmit.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

The patch adds skb_cow_header() to ensure enough headroom
at ip6erspan_tunnel_xmit before pushing the erspan header
to the skb.
Signed-off-by: William Tu <u9012063@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

When users fill in incorrect erspan version number through
the struct erspan_metadata uapi, current code skips pushing
the erspan header but continue pushing the gre header, which
is incorrect.  The patch fixes it by returning error.
Signed-off-by: William Tu <u9012063@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

The patch adds the erspan v2 proto in ip6gre_tunnel_lookup
so the erspan v2 tunnel can be found correctly.
Signed-off-by: William Tu <u9012063@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Ido Schimmel says:

====================
mlxsw: ACL and mirroring fixes

The first patch fixes offload of rules using the 'pass' action. Instead
of continuing to evaluate lower priority rules, the binding is
terminated and the packet proceeds to the bridge and router blocks on
ingress, or goes out of the port on egress.

Second patch prevents the user from mirroring more than once from a
given {Port, Direction} as this is not supported by the device.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

The Spectrum ASIC doesn't support mirroring more than once from a single
binding point (which is a port-direction pair). Therefore detect that a
second binding of a given binding point is attempted.

To that end, extend struct mlxsw_sp_span_inspected_port to track whether
a given binding point is bound or not. Extend
mlxsw_sp_span_entry_port_find() to look for ports based on the full
unique key: port number, direction, and boundness.

Besides fixing the overt bug where configured mirrors are not offloaded,
this also fixes a more subtle bug: mlxsw_sp_span_inspected_port_del()
just defers to mlxsw_sp_span_entry_bound_port_find(), and that used to
find the first port with the right number (disregarding the type). Thus
by adding and removing egress and ingress mirrors in the right order,
one could trick the system into believing it has no egress mirrors when
in fact it did have some. That then caused that
mlxsw_sp_span_port_mtu_update() didn't update mirroring buffer when MTU
was changed.

Fixes: 763b4b70 ("mlxsw: spectrum: Add support in matchall mirror TC offloading")
Signed-off-by: Petr Machata <petrm@mellanox.com>
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

For ok GACT action, TERMINATE binding_cmd should be used in action set
passed down to HW.

Fixes: b2925957 ("mlxsw: spectrum_flower: Offload "ok" termination action")
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Reported-by: Alexander Petrovskiy <alexpe@mellanox.com>
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Jason Wang says:

====================
Several fixes for vhost_net ptr_ring usage

This small series try to fix several bugs of ptr_ring usage in
vhost_net. Please review.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

After commit fc72d1d5 ("tuntap: XDP transmission"), we can
actually queueing XDP pointers in the pointer ring, so we should
examine the pointer type before freeing the pointer.

Fixes: fc72d1d5 ("tuntap: XDP transmission")
Reported-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

We get pointer ring from the exported sock, this means we should keep
rx_ring and vq->private synced during both vq stop and backend set,
otherwise we may see stale rx_ring.

Fixes: c67df11f ("vhost_net: try batch dequing from skb array")
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

KMSAN reported a use of uninit memory in vhost_net_buf_unproduce()
while trying to access n->vqs[VHOST_NET_VQ_TX].rx_ring:

==================================================================
BUG: KMSAN: use of uninitialized memory in vhost_net_buf_unproduce+0x7bb/0x9a0 drivers/vho
et.c:170
CPU: 0 PID: 3021 Comm: syz-fuzzer Not tainted 4.16.0-rc4+ #3853
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1 04/01/2014
Call Trace:
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0x185/0x1d0 lib/dump_stack.c:53
 kmsan_report+0x142/0x1f0 mm/kmsan/kmsan.c:1093
 __msan_warning_32+0x6c/0xb0 mm/kmsan/kmsan_instr.c:676
 vhost_net_buf_unproduce+0x7bb/0x9a0 drivers/vhost/net.c:170
 vhost_net_stop_vq drivers/vhost/net.c:974 [inline]
 vhost_net_stop+0x146/0x380 drivers/vhost/net.c:982
 vhost_net_release+0xb1/0x4f0 drivers/vhost/net.c:1015
 __fput+0x49f/0xa00 fs/file_table.c:209
 ____fput+0x37/0x40 fs/file_table.c:243
 task_work_run+0x243/0x2c0 kernel/task_work.c:113
 tracehook_notify_resume include/linux/tracehook.h:191 [inline]
 exit_to_usermode_loop arch/x86/entry/common.c:166 [inline]
 prepare_exit_to_usermode+0x349/0x3b0 arch/x86/entry/common.c:196
 syscall_return_slowpath+0xf3/0x6d0 arch/x86/entry/common.c:265
 do_syscall_64+0x34d/0x450 arch/x86/entry/common.c:292
...
origin:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:303 [inline]
 kmsan_internal_poison_shadow+0xb8/0x1b0 mm/kmsan/kmsan.c:213
 kmsan_kmalloc_large+0x6f/0xd0 mm/kmsan/kmsan.c:392
 kmalloc_large_node_hook mm/slub.c:1366 [inline]
 kmalloc_large_node mm/slub.c:3808 [inline]
 __kmalloc_node+0x100e/0x1290 mm/slub.c:3818
 kmalloc_node include/linux/slab.h:554 [inline]
 kvmalloc_node+0x1a5/0x2e0 mm/util.c:419
 kvmalloc include/linux/mm.h:541 [inline]
 vhost_net_open+0x64/0x5f0 drivers/vhost/net.c:921
 misc_open+0x7b5/0x8b0 drivers/char/misc.c:154
 chrdev_open+0xc28/0xd90 fs/char_dev.c:417
 do_dentry_open+0xccb/0x1430 fs/open.c:752
 vfs_open+0x272/0x2e0 fs/open.c:866
 do_last fs/namei.c:3378 [inline]
 path_openat+0x49ad/0x6580 fs/namei.c:3519
 do_filp_open+0x267/0x640 fs/namei.c:3553
 do_sys_open+0x6ad/0x9c0 fs/open.c:1059
 SYSC_openat+0xc7/0xe0 fs/open.c:1086
 SyS_openat+0x63/0x90 fs/open.c:1080
 do_syscall_64+0x2f1/0x450 arch/x86/entry/common.c:287
==================================================================

Fixes: c67df11f ("vhost_net: try batch dequing from skb array")
Signed-off-by: Alexander Potapenko <glider@google.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

This enables AVE_GI_RXDROP interrupt factor. This factor indicates
depletion of Rx descriptors and the handler counts the number
of dropped packets.
Signed-off-by: Kunihiko Hayashi <hayashi.kunihiko@socionext.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

As well as the basic conversion, I noticed that a lot of the
SCTP code checks gso_type without first checking skb_is_gso()
so I have added that where appropriate.

Also, document the helper.

Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: Daniel Axtens <dja@axtens.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

A tun device type can trivially be set to arbitrary value using
TUNSETLINK ioctl().

Therefore, lowpan_device_event() must really check that ieee802154_ptr
is not NULL.

Fixes: 2c88b528 ("ieee802154: 6lowpan: remove check on null")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Alexander Aring <alex.aring@gmail.com>
Cc: Stefan Schmidt <stefan@osg.samsung.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Acked-by: Stefan Schmidt <stefan@osg.samsung.com>
Signed-off-by: David S. Miller <davem@davemloft.net>