There is a regular need in the kernel to provide a way to declare having
a dynamically sized set of trailing elements in a structure. Kernel code
should always use “flexible array members”[1] for these cases. The older
style of one-element or zero-length arrays should no longer be used[2].

This helps with the ongoing efforts to globally enable -Warray-bounds
and get us closer to being able to tighten the FORTIFY_SOURCE routines
on memcpy().

This issue was found with the help of Coccinelle and audited and fixed,
manually.

[1] https://en.wikipedia.org/wiki/Flexible_array_member
[2] https://www.kernel.org/doc/html/v5.16/process/deprecated.html#zero-length-and-one-element-arrays

Link: https://github.com/KSPP/linux/issues/79Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Reviewed-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

Haiyang Zhang says:

====================
net: mana: Add handling of CQE_RX_TRUNCATED and a cleanup

Add handling of CQE_RX_TRUNCATED and a cleanup patch
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

The switch statement already ensures cqe_type == CQE_RX_OKAY at that
point.
Signed-off-by: Haiyang Zhang <haiyangz@microsoft.com>
Reviewed-by: Dexuan Cui <decui@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

The proper way to drop this kind of CQE is advancing rxq tail
without indicating the packet to the upper network layer.
Signed-off-by: Haiyang Zhang <haiyangz@microsoft.com>
Reviewed-by: Dexuan Cui <decui@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Eric Dumazet says:

====================
net: device tracking improvements

Main goal of this series is to be able to detect the following case
which apparently is still haunting us.

dev_hold_track(dev, tracker_1, GFP_ATOMIC);
    dev_hold(dev);
    dev_put(dev);
    dev_put(dev);              // Should complain loudly here.
dev_put_track(dev, tracker_1); // instead of here (as before this series)

v2: third patch:
  I replaced the dev_put() in linkwatch_do_dev() with __dev_put().
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

We are still chasing some syzbot reports where we think a rogue dev_put()
is called with no corresponding prior dev_hold().
Unfortunately it eats a reference on dev->dev_refcnt taken by innocent
dev_hold_track(), meaning that the refcount saturation splat comes
too late to be useful.

Make sure that 'not tracked' dev_put() and dev_hold() better use
CONFIG_NET_DEV_REFCNT_TRACKER=y debug infrastructure:

Prior patch in the series allowed ref_tracker_alloc() and ref_tracker_free()
to be called with a NULL @trackerp parameter, and to use a separate refcount
only to detect too many put() even in the following case:

dev_hold_track(dev, tracker_1, GFP_ATOMIC);
 dev_hold(dev);
 dev_put(dev);
 dev_put(dev); // Should complain loudly here.
dev_put_track(dev, tracker_1); // instead of here

Add clarification about netdev_tracker_alloc() role.

v2: I replaced the dev_put() in linkwatch_do_dev()
    with __dev_put() because callers called netdev_tracker_free().
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

We are still chasing a netdev refcount imbalance, and we suspect
we have one rogue dev_put() that is consuming a reference taken
from a dev_hold_track()

To detect this case, allow ref_tracker_alloc() and ref_tracker_free()
to be called with a NULL @trackerp parameter, and use a dedicated
refcount_t just for them.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Whenever ref_tracker_dir_init() is called, mark the struct ref_tracker_dir
as dead.

Test the dead status from ref_tracker_alloc() and ref_tracker_free()

This should detect buggy dev_put()/dev_hold() happening too late
in netdevice dismantle process.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Eric Dumazet says:

====================
ipv6: mc_forwarding changes

First patch removes minor data-races, as mc_forwarding can
be locklessly read in fast path.

Second patch adds a short cut in ip6mr_sk_done()
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

In many cases, ip6mr_sk_done() is called while no ipmr socket
has been registered.

This removes 4 rtnl acquisitions per netns dismantle,
with following callers:

igmp6_net_exit(), tcpv6_net_exit(), ndisc_net_exit()
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

This fixes minor data-races in ip6_mc_input() and
batadv_mcast_mla_rtr_flags_softif_get_ipv6()
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

We generally default the vendor to y and the drivers itself
to n. NET_DSA_REALTEK, however, selects a whole bunch of things,
so it's not a pure "vendor selection" knob. Let's default it all
to n.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Acked-by: Arınç ÜNAL <arinc.unal@arinc9.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

Phylink will use PCS polling whenever phylink_config.pcs_poll or the
phylink_pcs poll member is set. As this driver sets both, remove the
former.
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>

phylink_set_10g_modes() is no longer used with the conversion of
drivers to phylink_generic_validate(), so we can remove it.
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>

Paolo Abeni says:

====================
gro: a couple of minor optimization

This series collects a couple of small optimizations for the GRO engine,
reducing slightly the number of cycles for dev_gro_receive().
The delta is within noise range in tput tests, but with big TCP coming
every cycle saved from the GRO engine will count - I hope ;)

v1 -> v2:
 - a few cleanup suggested from Alexander(s)
 - moved away the more controversial 3rd patch
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

While inspecting some perf report, I noticed that the compiler
emits suboptimal code for the napi CB initialization, fetching
and storing multiple times the memory for flags bitfield.
This is with gcc 10.3.1, but I observed the same with older compiler
versions.

We can help the compiler to do a nicer work clearing several
fields at once using an u32 alias. The generated code is quite
smaller, with the same number of conditional.

Before:
objdump -t net/core/gro.o | grep " F .text"
0000000000000bb0 l     F .text	0000000000000357 dev_gro_receive

After:
0000000000000bb0 l     F .text	000000000000033c dev_gro_receive

v1  -> v2:
 - use struct_group (Alexander and Alex)

RFC -> v1:
 - use __struct_group to delimit the zeroed area (Alexander)
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

After commit 5e10da53 ("skbuff: allow 'slow_gro' for skb
carring sock reference") and commit af352460 ("net: fix GRO
skb truesize update") the truesize of the skb with stolen head is
properly updated by the GRO engine, we don't need anymore resetting
it at recycle time.

v1 -> v2:
 - clarify the commit message (Alexander)
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

This is a copy and paste bug.  It was supposed to check "clear_skb"
instead of "write_skb".

Fixes: 2cd54856 ("net: dsa: qca8k: add support for phy read/write with mgmt Ethernet")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Horatiu Vultur says:

====================
net: lan966x: add support for mcast snooping

Implement the switchdev callback SWITCHDEV_ATTR_ID_BRIDGE_MC_DISABLED
to allow to enable/disable multicast snooping.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

When the multicast snooping is disabled, the mdb entries should be
removed from the HW, but they still need to be kept in memory for when
the mcast_snooping will be enabled again.
Signed-off-by: Horatiu Vultur <horatiu.vultur@microchip.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

The callback allows to enable/disable multicast snooping.
When the snooping is enabled, all IGMP and MLD frames are redirected to
the CPU, therefore make sure not to set the skb flag 'offload_fwd_mark'.
The HW will not flood multicast ipv4/ipv6 data frames.
When the snooping is disabled, the HW will flood IGMP, MLD and multicast
ipv4/ipv6 frames according to the mcast_flood flag.
Signed-off-by: Horatiu Vultur <horatiu.vultur@microchip.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

When enabling the multicast snooping, the forwarding of the IPV6 frames
has it's own forwarding mask.
Signed-off-by: Horatiu Vultur <horatiu.vultur@microchip.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Currently tc skb extension is used to send miss info from
tc to ovs datapath module, and driver to tc. For the tc to ovs
miss it is currently always allocated even if it will not
be used by ovs datapath (as it depends on a requested feature).

Export the static key which is used by openvswitch module to
guard this code path as well, so it will be skipped if ovs
datapath doesn't need it. Enable this code path once
ovs datapath needs it.
Signed-off-by: Paul Blakey <paulb@nvidia.com>
Reviewed-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Mat Martineau says:

====================
mptcp: Improve set-flags command and update self tests

Patches 1-3 allow more flexibility in the combinations of features and
flags allowed with the MPTCP_PM_CMD_SET_FLAGS netlink command, and add
self test case coverage for the new functionality.

Patches 4-6 and 9 refactor the mptcp_join.sh self tests to allow them to
configure all of the test cases using either the pm_nl_ctl utility (part
of the mptcp self tests) or the 'ip mptcp' command (from iproute2). The
default remains to use pm_nl_ctl.

Patches 7 and 8 update the pm_netlink.sh self tests to cover the use of
endpoint ids to set endpoint flags (instead of just addresses).
====================

Link: https://lore.kernel.org/r/20220205000337.187292-1-mathew.j.martineau@linux.intel.comSigned-off-by: Jakub Kicinski <kuba@kernel.org>

This patch added a command line option '-i' for mptcp_join.sh to use
'ip mptcp' commands instead of using 'pm_nl_ctl' commands to deal with
PM netlink.
Signed-off-by: Geliang Tang <geliang.tang@suse.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

This patch added the setting flags test cases, using both addr-based and
id-based lookups for the setting address.

The output looks like this:

 set flags (backup)                                 [ OK ]
           (nobackup)                               [ OK ]
           (fullmesh)                               [ OK ]
           (nofullmesh)                             [ OK ]
           (backup,fullmesh)                        [ OK ]
Signed-off-by: Geliang Tang <geliang.tang@suse.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

This patch added the id argument for setting the address flags in
pm_nl_ctl.

Usage:

    pm_nl_ctl set id 1 flags backup
Signed-off-by: Geliang Tang <geliang.tang@suse.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

This patch implemented a new function named pm_nl_set_endpoint(), wrapped
the PM netlink commands 'ip mptcp endpoint change flags' and 'pm_nl_ctl
set flags' in it, and used a new argument 'ip_mptcp' to choose which one
to use to set the flags of the PM endpoint.

'ip mptcp' used the ID number argument to find out the address to change
flags, while 'pm_nl_ctl' used the address and port number arguments. So
we need to parse the address ID from the PM dump output as well as the
address and port number.

Used this wrapper in do_transfer() instead of using the pm_nl_ctl command
directly.
Signed-off-by: Geliang Tang <geliang.tang@suse.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

This patch implemented a new function named pm_nl_show_endpoints(), wrapped
the PM netlink commands 'ip mptcp endpoint show' and 'pm_nl_ctl dump' in
it, used a new argument 'ip_mptcp' to choose which one to use to show all
the PM endpoints.

Used this wrapper in do_transfer() instead of using the pm_nl_ctl commands
directly.

The original 'pos+=5' in the remoing tests only works for the output of
'pm_nl_ctl show':

  id 1 flags subflow 10.0.1.1

It doesn't work for the output of 'ip mptcp endpoint show':

  10.0.1.1 id 1 subflow

So implemented a more flexible approach to get the address ID from the PM
dump output to fit for both commands.
Signed-off-by: Geliang Tang <geliang.tang@suse.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

This patch added four basic 'ip mptcp' wrappers:

pm_nl_set_limits()
pm_nl_add_endpoint()
pm_nl_del_endpoint()
pm_nl_flush_endpoint().

Wrapped the PM netlink commands 'ip mptcp' and 'pm_nl_ctl' in them, and
used a new argument 'ip_mptcp' to choose which one to use for setting the
PM limits, adding or deleting the PM endpoint.

Used the wrappers in all the selftests in mptcp_join.sh instead of using
the pm_nl_ctl commands directly.
Signed-off-by: Geliang Tang <geliang.tang@suse.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

This patch added the backup testcase using an address with a port number.

The original backup tests only work for the output of 'pm_nl_ctl dump'
without the port number. It chooses the last item in the dump to parse
the address in it, and in this case, the address is showed at the end
of the item.

But it doesn't work for the dump with the port number, in this case, the
port number is showed at the end of the item, not the address.

So implemented a more flexible approach to get the address and the port
number from the dump to fit for the port number case.
Signed-off-by: Geliang Tang <geliang.tang@suse.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

This patch added the port argument for setting the address flags in
pm_nl_ctl.

Usage:

    pm_nl_ctl set 10.0.2.1 flags backup port 10100
Signed-off-by: Geliang Tang <geliang.tang@suse.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

It's illegal to use both port and non-signal flags for adding address.
But it's legal to use both of them for setting flags, which always uses
non-signal flags, backup or fullmesh.

This patch moves this non-signal flag with port check from
mptcp_pm_parse_addr() to mptcp_nl_cmd_add_addr(). Do the check only when
adding addresses, not setting flags or deleting addresses.
Signed-off-by: Geliang Tang <geliang.tang@suse.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Justin Iurman says:

====================
Support for the IOAM insertion frequency

The insertion frequency is represented as "k/n", meaning IOAM will be
added to {k} packets over {n} packets, with 0 < k <= n and 1 <= {k,n} <=
1000000. Therefore, it provides the following percentages of insertion
frequency: [0.0001% (min) ... 100% (max)].

Not only this solution allows an operator to apply dynamic frequencies
based on the current traffic load, but it also provides some
flexibility, i.e., by distinguishing similar cases (e.g., "1/2" and
"2/4").

"1/2" = Y N Y N Y N Y N ...
"2/4" = Y Y N N Y Y N N ...
====================

Link: https://lore.kernel.org/r/20220202142554.9691-1-justin.iurman@uliege.beSigned-off-by: Jakub Kicinski <kuba@kernel.org>

Add support for the IOAM insertion frequency inside its lwtunnel output
function. This patch introduces a new (atomic) counter for packets,
based on which the algorithm will decide if IOAM should be added or not.

Default frequency is "1/1" (i.e., applied to all packets) for backward
compatibility. The iproute2 patch is ready and will be submitted as soon
as this one is accepted.

Previous iproute2 command:
ip -6 ro ad fc00::1/128 encap ioam6 [ mode ... ] ...

New iproute2 command:
ip -6 ro ad fc00::1/128 encap ioam6 [ freq k/n ] [ mode ... ] ...
Signed-off-by: Justin Iurman <justin.iurman@uliege.be>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Add the insertion frequency uapi for IOAM lwtunnels.
Signed-off-by: Justin Iurman <justin.iurman@uliege.be>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Nothing in ipv6.h needs ndisc.h, drop it.

Link: https://lore.kernel.org/r/20220203043457.2222388-1-kuba@kernel.orgAcked-by: Jeremy Kerr <jk@codeconstruct.com.au>
Acked-by: Stefan Schmidt <stefan@datenfreihafen.org>
Link: https://lore.kernel.org/r/20220203231240.2297588-1-kuba@kernel.orgReviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Alex Elder says:

====================
net: ipa: improve RX buffer replenishing

This series revises the algorithm used for replenishing receive
buffers on RX endpoints.  Currently there are two atomic variables
that track how many receive buffers can be sent to the hardware.
The new algorithm obviates the need for those, by just assuming we
always want to provide the hardware with buffers until it can hold
no more.

The first patch eliminates an atomic variable that's not required.
The next moves some code into the main replenish function's caller,
making one of the called function's arguments unnecessary.   The
next six refactor things a bit more, adding a new helper function
that allows us to eliminate an additional atomic variable.  And the
final two implement two more minor improvements.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

Rather than tracking the number of receive buffer transactions that
have been submitted without a doorbell, just track the total number
of transactions that have been issued.  Then ring the doorbell when
that number modulo the replenish batch size is 0.

The effect is roughly the same, but the new count is slightly more
interesting, and this approach will someday allow the replenish
batch size to be tuned at runtime.
Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

Replenishing is now solely driven by whether transactions are
available for a channel, and it doesn't really matter whether
we replenish before or after we deliver received packets to the
network stack.

Replenishing before delivering the payload adds a little latency.
Eliminate that by requesting a replenish after the payload is
delivered.
Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>