aarch64 doesn't have native store immediate instruction, such operation
has to be implemented by the below instruction sequence:

Load immediate to register
Store register
Signed-off-by: NYang Shi <yang.shi@linaro.org>
CC: Zi Shen Lim <zlim.lnx@gmail.com>
CC: Xi Wang <xi.wang@gmail.com>
Reviewed-by: NZi Shen Lim <zlim.lnx@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

While testing the np->opt RCU conversion, I found that UDP/IPv6 was
using a mixture of xchg() and sk_dst_lock to protect concurrent changes
to sk->sk_dst_cache, leading to possible corruptions and crashes.

ip6_sk_dst_lookup_flow() uses sk_dst_check() anyway, so the simplest
way to fix the mess is to remove sk_dst_lock completely, as we did for
IPv4.

__ip6_dst_store() and ip6_dst_store() share same implementation.

sk_setup_caps() being called with socket lock being held or not,
we have to use sk_dst_set() instead of __sk_dst_set()

Note that I had to move the "np->dst_cookie = rt6_get_cookie(rt);"
in ip6_dst_store() before the sk_setup_caps(sk, dst) call.

This is because ip6_dst_store() can be called from process context,
without any lock held.

As soon as the dst is installed in sk->sk_dst_cache, dst can be freed
from another cpu doing a concurrent ip6_dst_store()

Doing the dst dereference before doing the install is needed to make
sure no use after free would trigger.
Signed-off-by: NEric Dumazet <edumazet@google.com>
Reported-by: NDmitry Vyukov <dvyukov@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch completes the work I did in commit 45f6fad8
("ipv6: add complete rcu protection around np->opt"), as I missed
sctp part.

This simply makes sure np->opt is used with proper RCU locking
and accessors.
Signed-off-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Proxy entries could have null pointer to net-device.
Signed-off-by: NKonstantin Khlebnikov <koct9i@gmail.com>
Fixes: 84920c14 ("net: Allow ipv6 proxies and arp proxies be shown with iproute2")
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Dmitry Vyukov reported that the user could trigger a kernel warning by
using a large len value for getsockopt SCTP_GET_LOCAL_ADDRS, as that
value directly affects the value used as a kmalloc() parameter.

This patch thus switches the allocation flags from all user-controllable
kmalloc size to GFP_USER to put some more restrictions on it and also
disables the warn, as they are not necessary.
Signed-off-by: NMarcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Acked-by: NDaniel Borkmann <daniel@iogearbox.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

They don't need to be any bigger than that and with this we start a new
bitfield for tracking association runtime stuff, like zero window
situation.
Signed-off-by: NMarcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Acked-by: NVlad Yasevich <vyasevich@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch addresses multiple problems :

UDP/RAW sendmsg() need to get a stable struct ipv6_txoptions
while socket is not locked : Other threads can change np->opt
concurrently. Dmitry posted a syzkaller
(http://github.com/google/syzkaller) program desmonstrating
use-after-free.

Starting with TCP/DCCP lockless listeners, tcp_v6_syn_recv_sock()
and dccp_v6_request_recv_sock() also need to use RCU protection
to dereference np->opt once (before calling ipv6_dup_options())

This patch adds full RCU protection to np->opt
Reported-by: NDmitry Vyukov <dvyukov@google.com>
Signed-off-by: NEric Dumazet <edumazet@google.com>
Acked-by: NHannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

For large map->value_size the user space can trigger memory allocation warnings like:
WARNING: CPU: 2 PID: 11122 at mm/page_alloc.c:2989
__alloc_pages_nodemask+0x695/0x14e0()
Call Trace:
 [<     inline     >] __dump_stack lib/dump_stack.c:15
 [<ffffffff82743b56>] dump_stack+0x68/0x92 lib/dump_stack.c:50
 [<ffffffff81244ec9>] warn_slowpath_common+0xd9/0x140 kernel/panic.c:460
 [<ffffffff812450f9>] warn_slowpath_null+0x29/0x30 kernel/panic.c:493
 [<     inline     >] __alloc_pages_slowpath mm/page_alloc.c:2989
 [<ffffffff81554e95>] __alloc_pages_nodemask+0x695/0x14e0 mm/page_alloc.c:3235
 [<ffffffff816188fe>] alloc_pages_current+0xee/0x340 mm/mempolicy.c:2055
 [<     inline     >] alloc_pages include/linux/gfp.h:451
 [<ffffffff81550706>] alloc_kmem_pages+0x16/0xf0 mm/page_alloc.c:3414
 [<ffffffff815a1c89>] kmalloc_order+0x19/0x60 mm/slab_common.c:1007
 [<ffffffff815a1cef>] kmalloc_order_trace+0x1f/0xa0 mm/slab_common.c:1018
 [<     inline     >] kmalloc_large include/linux/slab.h:390
 [<ffffffff81627784>] __kmalloc+0x234/0x250 mm/slub.c:3525
 [<     inline     >] kmalloc include/linux/slab.h:463
 [<     inline     >] map_update_elem kernel/bpf/syscall.c:288
 [<     inline     >] SYSC_bpf kernel/bpf/syscall.c:744

To avoid never succeeding kmalloc with order >= MAX_ORDER check that
elem->value_size and computed elem_size are within limits for both hash and
array type maps.
Also add __GFP_NOWARN to kmalloc(value_size | elem_size) to avoid OOM warnings.
Note kmalloc(key_size) is highly unlikely to trigger OOM, since key_size <= 512,
so keep those kmalloc-s as-is.

Large value_size can cause integer overflows in elem_size and map.pages
formulas, so check for that as well.

Fixes: aaac3ba9 ("bpf: charge user for creation of BPF maps and programs")
Reported-by: NDmitry Vyukov <dvyukov@google.com>
Signed-off-by: NAlexei Starovoitov <ast@kernel.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Marcin Wojtas says:

====================
Marvell Armada XP/370/38X Neta fixes

I'm sending v4 with corrected commit log of the last patch, in order to
avoid possible conflicts between the branches as suggested by Gregory
Clement.

Best regards,
Marcin Wojtas

Changes from v4:
* Correct commit log of patch 6/6

Changes from v2:
* Style fixes in patch updating mbus protection
* Remove redundant stable notifications except for patch 4/6

Changes from v1:
* update MBUS windows access protection register once, after whole loop
* add fixing value of MVNETA_RXQ_INTR_ENABLE_ALL_MASK
* add fixing error path for skb_build()
* add possibility of setting custom TX IP checksum limit in DT property
====================
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The Ethernet controller found in the Armada 38x SoC's family support
TCP/IP checksumming with frame sizes larger than 1600 bytes, however
only on port 0.

This commit enables it by setting 'tx-csum-limit' to 9800B in
'ethernet@70000' node.
Signed-off-by: NMarcin Wojtas <mw@semihalf.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Since Armada 38x SoC can support IP checksum for jumbo frames only on
a single port, it means that this feature should be enabled per-port,
rather than for the whole SoC.

This patch enables setting custom TX IP checksum limit by adding new
optional property to the mvneta device tree node. If not used, by
default 1600B is set for "marvell,armada-370-neta" and 9800B for other
strings, which ensures backward compatibility. Binding documentation
is updated accordingly.
Signed-off-by: NMarcin Wojtas <mw@semihalf.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

In the actual RX processing, there is same error path for both descriptor
ring refilling and building skb fails. This is not correct, because after
successful refill, the ring is already updated with newly allocated
buffer. Then, in case of build_skb() fail, hitherto code left the original
buffer unmapped.

This patch fixes above situation by swapping error check of skb build with
DMA-unmap of original buffer.
Signed-off-by: NMarcin Wojtas <mw@semihalf.com>
Acked-by: NSimon Guinot <simon.guinot@sequanux.org>
Cc: <stable@vger.kernel.org> # v4.2+
Fixes a84e3289 ("net: mvneta: fix refilling for Rx DMA buffers")
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

A value originally defined in the driver was inappropriate. Even though
the ingress was somehow working, writing MVNETA_RXQ_INTR_ENABLE_ALL_MASK
to MVNETA_INTR_ENABLE didn't make any effect, because the bits [31:16]
are reserved and read-only.

This commit updates MVNETA_RXQ_INTR_ENABLE_ALL_MASK to be compliant with
the controller's documentation.
Signed-off-by: NMarcin Wojtas <mw@semihalf.com>

Fixes: c5aff182 ("net: mvneta: driver for Marvell Armada 370/XP network
unit")
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

MVNETA_RXQ_HW_BUF_ALLOC bit which controls enabling hardware buffer
allocation was mistakenly set as BIT(1). This commit fixes the assignment.
Signed-off-by: NMarcin Wojtas <mw@semihalf.com>
Reviewed-by: NGregory CLEMENT <gregory.clement@free-electrons.com>

Fixes: c5aff182 ("net: mvneta: driver for Marvell Armada 370/XP network
unit")
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This commit adds missing configuration of MBUS windows access protection
in mvneta_conf_mbus_windows function - a dedicated variable for that
purpose remained there unused since v3.8 initial mvneta support. Because
of that the register contents were inherited from the bootloader.
Signed-off-by: NMarcin Wojtas <mw@semihalf.com>
Reviewed-by: NGregory CLEMENT <gregory.clement@free-electrons.com>

Fixes: c5aff182 ("net: mvneta: driver for Marvell Armada 370/XP network
unit")
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Sunil Goutham says:

====================
thunderx: miscellaneous fixes

This patch series contains fixes for various issues observed
with BGX and NIC drivers.

Changes from v1:
- Fixed comment syle in the first patch of the series
- Removed 'Increase transmit queue length' patch from the series,
  will recheck if it's a driver or system issue and resubmit.
====================
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Enable or disable BGX LMAC's RX/TX based on corresponding VF's
status. If otherwise, when multiple LMAC's physical link is up
then packets from all LMAC's whose corresponding VF is not yet
initialized will get forwarded to VF0. This is due to VNIC's default
configuration where CPI, RSSI e.t.c point to VF0/QSET0/RQ0.

This patch will prevent multiple copies of packets on VF0.
Signed-off-by: NSunil Goutham <sgoutham@cavium.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Call netif_carrier_on() only if interface's link is up. Switching this on
upon IFF_UP by default, is causing issues with ethernet channel bonding
in LACP mode. Initial NETDEV_CHANGE notification was being skipped.

Also fixed some issues with link/speed/duplex reporting via ethtool.
Signed-off-by: NSunil Goutham <sgoutham@cavium.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Properly set CQ timer threshold and also set it to 2us.
With previous incorrect settings it was set to 0.5us which is too less.
Signed-off-by: NSunil Goutham <sgoutham@cavium.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

While VNIC or BGX driver teardown, wait for already scheduled delayed work to
finish before destroying it.
Signed-off-by: NThanneeru Srinivasulu <tsrinivasulu@caviumnetworks.com>
Signed-off-by: NSunil Goutham <sgoutham@cavium.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NThanneeru Srinivasulu <tsrinivasulu@caviumnetworks.com>
Signed-off-by: NSunil Goutham <sgoutham@cavium.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

After 614732ea, no refcount is maintained for the vport-vxlan module.
This allows the userspace to remove such module while vport-vxlan
devices still exist, which leads to later oops.

v1 -> v2:
 - move vport 'owner' initialization in ovs_vport_ops_register()
   and make such function a macro

Fixes: 614732ea ("openvswitch: Use regular VXLAN net_device device")
Signed-off-by: NPaolo Abeni <pabeni@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

During own review but also reported by Dmitry's syzkaller [1] it has been
noticed that we trigger a heap out-of-bounds access on eBPF array maps
when updating elements. This happens with each map whose map->value_size
(specified during map creation time) is not multiple of 8 bytes.

In array_map_alloc(), elem_size is round_up(attr->value_size, 8) and
used to align array map slots for faster access. However, in function
array_map_update_elem(), we update the element as ...

memcpy(array->value + array->elem_size * index, value, array->elem_size);

... where we access 'value' out-of-bounds, since it was allocated from
map_update_elem() from syscall side as kmalloc(map->value_size, GFP_USER)
and later on copied through copy_from_user(value, uvalue, map->value_size).
Thus, up to 7 bytes, we can access out-of-bounds.

Same could happen from within an eBPF program, where in worst case we
access beyond an eBPF program's designated stack.

Since 1be7f75d ("bpf: enable non-root eBPF programs") didn't hit an
official release yet, it only affects priviledged users.

In case of array_map_lookup_elem(), the verifier prevents eBPF programs
from accessing beyond map->value_size through check_map_access(). Also
from syscall side map_lookup_elem() only copies map->value_size back to
user, so nothing could leak.

  [1] http://github.com/google/syzkaller

Fixes: 28fbcfa0 ("bpf: add array type of eBPF maps")
Reported-by: NDmitry Vyukov <dvyukov@google.com>
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>
Acked-by: NAlexei Starovoitov <ast@kernel.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Dmitry provided a syzkaller (http://github.com/google/syzkaller)
triggering a fault in sock_wake_async() when async IO is requested.

Said program stressed af_unix sockets, but the issue is generic
and should be addressed in core networking stack.

The problem is that by the time sock_wake_async() is called,
we should not access the @flags field of 'struct socket',
as the inode containing this socket might be freed without
further notice, and without RCU grace period.

We already maintain an RCU protected structure, "struct socket_wq"
so moving SOCKWQ_ASYNC_NOSPACE & SOCKWQ_ASYNC_WAITDATA into it
is the safe route.

It also reduces number of cache lines needing dirtying, so might
provide a performance improvement anyway.

In followup patches, we might move remaining flags (SOCK_NOSPACE,
SOCK_PASSCRED, SOCK_PASSSEC) to save 8 bytes and let 'struct socket'
being mostly read and let it being shared between cpus.
Reported-by: NDmitry Vyukov <dvyukov@google.com>
Signed-off-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch is a cleanup to make following patch easier to
review.

Goal is to move SOCK_ASYNC_NOSPACE and SOCK_ASYNC_WAITDATA
from (struct socket)->flags to a (struct socket_wq)->flags
to benefit from RCU protection in sock_wake_async()

To ease backports, we rename both constants.

Two new helpers, sk_set_bit(int nr, struct sock *sk)
and sk_clear_bit(int net, struct sock *sk) are added so that
following patch can change their implementation.
Signed-off-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

vmxnet3_drv does not check dma_addr with dma_mapping_error()
after mapping dma memory. The patch adds the checks and
tries to handle failures.

Found by Linux Driver Verification project (linuxtesting.org).
Signed-off-by: NAlexey Khoroshilov <khoroshilov@ispras.ru>
Acked-by: NShrikrishna Khare <skhare@vmware.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The N_X25 line discipline may access the previous line discipline's closed
and already-freed private data on open [1].

The tty->disc_data field _never_ refers to valid data on entry to the
line discipline's open() method. Rather, the ldisc is expected to
initialize that field for its own use for the lifetime of the instance
(ie. from open() to close() only).

[1]
    [  634.336761] ==================================================================
    [  634.338226] BUG: KASAN: use-after-free in x25_asy_open_tty+0x13d/0x490 at addr ffff8800a743efd0
    [  634.339558] Read of size 4 by task syzkaller_execu/8981
    [  634.340359] =============================================================================
    [  634.341598] BUG kmalloc-512 (Not tainted): kasan: bad access detected
    ...
    [  634.405018] Call Trace:
    [  634.405277] dump_stack (lib/dump_stack.c:52)
    [  634.405775] print_trailer (mm/slub.c:655)
    [  634.406361] object_err (mm/slub.c:662)
    [  634.406824] kasan_report_error (mm/kasan/report.c:138 mm/kasan/report.c:236)
    [  634.409581] __asan_report_load4_noabort (mm/kasan/report.c:279)
    [  634.411355] x25_asy_open_tty (drivers/net/wan/x25_asy.c:559 (discriminator 1))
    [  634.413997] tty_ldisc_open.isra.2 (drivers/tty/tty_ldisc.c:447)
    [  634.414549] tty_set_ldisc (drivers/tty/tty_ldisc.c:567)
    [  634.415057] tty_ioctl (drivers/tty/tty_io.c:2646 drivers/tty/tty_io.c:2879)
    [  634.423524] do_vfs_ioctl (fs/ioctl.c:43 fs/ioctl.c:607)
    [  634.427491] SyS_ioctl (fs/ioctl.c:622 fs/ioctl.c:613)
    [  634.427945] entry_SYSCALL_64_fastpath (arch/x86/entry/entry_64.S:188)
Reported-and-tested-by: NSasha Levin <sasha.levin@oracle.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: NPeter Hurley <peter@hurleysoftware.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This reverts commit ab450605.

In IPv6, we cannot inherit the dst of the original dst. ndisc packets
are IPv6 packets and may take another route than the original packet.

This patch breaks the following scenario: a packet comes from eth0 and
is forwarded through vxlan1. The encapsulated packet triggers an NS
which cannot be sent because of the wrong route.

CC: Jiri Benc <jbenc@redhat.com>
CC: Thomas Graf <tgraf@suug.ch>
Signed-off-by: NNicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Dmitry provided a syzkaller (http://github.com/google/syzkaller)
generated program that triggers the WARNING at
net/ipv4/tcp.c:1729 in tcp_recvmsg() :

WARN_ON(tp->copied_seq != tp->rcv_nxt &&
        !(flags & (MSG_PEEK | MSG_TRUNC)));

His program is specifically attempting a Cross SYN TCP exchange,
that we support (for the pleasure of hackers ?), but it looks we
lack proper tcp->copied_seq initialization.

Thanks again Dmitry for your report and testings.
Signed-off-by: NEric Dumazet <edumazet@google.com>
Reported-by: NDmitry Vyukov <dvyukov@google.com>
Tested-by: NDmitry Vyukov <dvyukov@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The gianfar driver has recently been enabled on arm64 but fails to build
since it check the return value of platform_get_irq() against NO_IRQ. Fix
this by instead checking for a negative error code.

Even on ARM where this code was previously being built this check was
incorrect since platform_get_irq() returns a negative error code which
may not be exactly the (unsigned int)(-1) that NO_IRQ is defined to be.
Signed-off-by: NMark Brown <broonie@kernel.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This driver can be built on arm64 but relies on NO_IRQ to check the return
value of irq_of_parse_and_map() which fails to build on arm64 because the
architecture does not provide a NO_IRQ. Fix this to correctly check the
return value of irq_of_parse_and_map().

Even on ARM systems where the driver was previously used the check was
broken since on ARM NO_IRQ is -1 but irq_of_parse_and_map() returns 0 on
error.
Signed-off-by: NMark Brown <broonie@kernel.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

sendpage did not care about credentials at all. This could lead to
situations in which because of fd passing between processes we could
append data to skbs with different scm data. It is illegal to splice those
skbs together. Instead we have to allocate a new skb and if requested
fill out the scm details.

Fixes: 869e7c62 ("net: af_unix: implement stream sendpage support")
Reported-by: NAl Viro <viro@zeniv.linux.org.uk>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Eric Dumazet <edumazet@google.com>
Signed-off-by: NHannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Giuseppe Cavallaro says:

====================
Spare stmmac fixes

These are some fixes for the stmmac d.d. tested on STi platforms.
They are for some part of the PM, STi glue and rx path when test
Jumbo.
====================
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The receive skb buffers can be preallocated when the link is opened
according to mtu size.
While testing on a network environment with not standard MTU (e.g. 3000),
a panic occurred if an incoming packet had a length greater than rx skb
buffer size. This is because the HW is programmed to copy, from the DMA,
an Jumbo frame and the Sw must check if the allocated buffer is enough to
store the frame.
Signed-off-by: NAlexandre TORGUE <alexandre.torgue@st.com>
Signed-off-by: NGiuseppe Cavallaro <peppe.cavallaro@st.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When stmmac_mdio_reset, was called from stmmac_resume, it was not
resetting the PHY due to which MAC was not getting reset properly and
hence ethernet interface not was resumed properly.
The issue was currently only reproducible on stih301-b2204.
Signed-off-by: NPankaj Dev <pankaj.dev@st.com>
Signed-off-by: NGiuseppe Cavallaro <peppe.cavallaro@st.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

In case of the st,tx-retime-src is missing from device-tree
(it's an optional field) the driver will invoke the strcasecmp to check
which clock has been selected and this is a bug; the else condition
is needed.

In the dwmac_setup, the "rs" variable, passed to the strcasecmp, was not
initialized and the compiler, depending on the options adopted, could
take it in some different part of the stack generating the hang in such
configuration.
Signed-off-by: NGiuseppe Cavallaro <peppe.cavallaro@st.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch is to fix the csr clock in case of 300MHz is provided.
Reported-by: NKent Borg <Kent.Borg@csr.com>
Signed-off-by: NGiuseppe Cavallaro <peppe.cavallaro@st.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When resume the HW is re-configured but some settings can be lost.
For example, the MAC Address_X High/Low Registers used for VLAN tagging..
So, while resuming, the set_filter callback needs to be invoked to
re-program perfect and hash-table registers.
Signed-off-by: NGiuseppe Cavallaro <peppe.cavallaro@st.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Once TX has been enabled on a NIC, it is illegal to access skb,
as this skb might have been freed by another cpu, from TX completion
handler.
Signed-off-by: NEric Dumazet <edumazet@google.com>
Reported-by: NMark Rutland <mark.rutland@arm.com>
Tested-by: NMark Rutland <mark.rutland@arm.com>
Cc: Iyappan Subramanian <isubramanian@apm.com>
Acked-by: NIyappan Subramanian <isubramanian@apm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Commit 9c707762 ("packet: make packet_snd fail on len smaller
than l2 header") added validation for the packet size in packet_snd.
This change enforces that every packet needs a header (with at least
hard_header_len bytes) plus a payload with at least one byte. Before
this change the payload was optional.

This fixes PPPoE connections which do not have a "Service" or
"Host-Uniq" configured (which is violating the spec, but is still
widely used in real-world setups). Those are currently failing with the
following message: "pppd: packet size is too short (24 <= 24)"
Signed-off-by: NMartin Blumenstingl <martin.blumenstingl@googlemail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>