Commit Graph

65504 Commits

Author SHA1 Message Date
Guvenc Gulce
17081633e2 net/smc: Ensure correct state of the socket in send path
When smc_sendmsg() is called before the SMC socket initialization has
completed, smc_tx_sendmsg() will access un-initialized fields of the
SMC socket which results in a null-pointer dereference.
Fix this by checking the socket state first in smc_tx_sendmsg().

Fixes: e0e4b8fa53 ("net/smc: Add SMC statistics support")
Reported-by: syzbot+5dda108b672b54141857@syzkaller.appspotmail.com
Reviewed-by: Karsten Graul <kgraul@linux.ibm.com>
Signed-off-by: Guvenc Gulce <guvenc@linux.ibm.com>
Signed-off-by: Karsten Graul <kgraul@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-25 11:53:51 -07:00
zhang kai
c305b9e6d5 ipv6: delete useless dst check in ip6_dst_lookup_tail
parameter dst always points to null.

Signed-off-by: zhang kai <zhangkaiheb@126.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-24 15:49:01 -07:00
Xin Long
fea1d5b17f sctp: send the next probe immediately once the last one is acked
These is no need to wait for 'interval' period for the next probe
if the last probe is already acked in search state. The 'interval'
period waiting should be only for probe failure timeout and the
current pmtu check when it's in search complete state.

This change will shorten the probe time a lot in search state, and
also fix the document accordingly.

Signed-off-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-24 12:58:03 -07:00
Xin Long
0dac127c05 sctp: do black hole detection in search complete state
Currently the PLPMUTD probe will stop for a long period (interval * 30)
after it enters search complete state. If there's a pmtu change on the
route path, it takes a long time to be aware if the ICMP TooBig packet
is lost or filtered.

As it says in rfc8899#section-4.3:

  "A DPLPMTUD method MUST NOT rely solely on this method."
  (ICMP PTB message).

This patch is to enable the other method for search complete state:

  "A PL can use the DPLPMTUD probing mechanism to periodically
   generate probe packets of the size of the current PLPMTU."

With this patch, the probe will continue with the current pmtu every
'interval' until the PMTU_RAISE_TIMER 'timeout', which we implement
by adding raise_count to raise the probe size when it counts to 30
and removing the SCTP_PL_COMPLETE check for PMTU_RAISE_TIMER.

Signed-off-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-24 12:58:03 -07:00
Jakub Kicinski
6d123b81ac net: ip: avoid OOM kills with large UDP sends over loopback
Dave observed number of machines hitting OOM on the UDP send
path. The workload seems to be sending large UDP packets over
loopback. Since loopback has MTU of 64k kernel will try to
allocate an skb with up to 64k of head space. This has a good
chance of failing under memory pressure. What's worse if
the message length is <32k the allocation may trigger an
OOM killer.

This is entirely avoidable, we can use an skb with page frags.

af_unix solves a similar problem by limiting the head
length to SKB_MAX_ALLOC. This seems like a good and simple
approach. It means that UDP messages > 16kB will now
use fragments if underlying device supports SG, if extra
allocator pressure causes regressions in real workloads
we can switch to trying the large allocation first and
falling back.

v4: pre-calculate all the additions to alloclen so
    we can be sure it won't go over order-2

Reported-by: Dave Jones <dsj@fb.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-24 11:17:21 -07:00
Martynas Pumputis
e8b9eab992 net: retrieve netns cookie via getsocketopt
It's getting more common to run nested container environments for
testing cloud software. One of such examples is Kind [1] which runs a
Kubernetes cluster in Docker containers on a single host. Each container
acts as a Kubernetes node, and thus can run any Pod (aka container)
inside the former. This approach simplifies testing a lot, as it
eliminates complicated VM setups.

Unfortunately, such a setup breaks some functionality when cgroupv2 BPF
programs are used for load-balancing. The load-balancer BPF program
needs to detect whether a request originates from the host netns or a
container netns in order to allow some access, e.g. to a service via a
loopback IP address. Typically, the programs detect this by comparing
netns cookies with the one of the init ns via a call to
bpf_get_netns_cookie(NULL). However, in nested environments the latter
cannot be used given the Kubernetes node's netns is outside the init ns.
To fix this, we need to pass the Kubernetes node netns cookie to the
program in a different way: by extending getsockopt() with a
SO_NETNS_COOKIE option, the orchestrator which runs in the Kubernetes
node netns can retrieve the cookie and pass it to the program instead.

Thus, this is following up on Eric's commit 3d368ab87c ("net:
initialize net->net_cookie at netns setup") to allow retrieval via
SO_NETNS_COOKIE.  This is also in line in how we retrieve socket cookie
via SO_COOKIE.

  [1] https://kind.sigs.k8s.io/

Signed-off-by: Lorenz Bauer <lmb@cloudflare.com>
Signed-off-by: Martynas Pumputis <m@lambda.lt>
Cc: Eric Dumazet <edumazet@google.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-24 11:13:05 -07:00
Dmytro Linkin
a3e5e5797f devlink: Protect rate list with lock while switching modes
Devlink eswitch set command doesn't hold devlink->lock, which makes
possible race condition between rate list traversing and others devlink
rate KAPI calls, like devlink_rate_nodes_destroy().
Hold devlink lock while traversing the list.

Fixes: a8ecb93ef0 ("devlink: Introduce rate nodes")
Signed-off-by: Dmytro Linkin <dlinkin@nvidia.com>
Reviewed-by: Parav Pandit <parav@nvidia.com>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-23 15:46:25 -07:00
Dmytro Linkin
ff99324ded devlink: Remove eswitch mode check for mode set call
When eswitch is disabled, querying its current mode results in error.
Due to this when trying to set the eswitch mode for mlx5 devices, it
fails to set the eswitch switchdev mode.
Hence remove such check.

Fixes: a8ecb93ef0 ("devlink: Introduce rate nodes")
Signed-off-by: Dmytro Linkin <dlinkin@nvidia.com>
Reviewed-by: Parav Pandit <parav@nvidia.com>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-23 15:46:25 -07:00
Dmytro Linkin
1321ed5e76 devlink: Decrease refcnt of parent rate object on leaf destroy
Port functions, like SFs, can be deleted by the user when its leaf rate
object has parent node. In such case node refcnt won't be decreased
which blocks the node from deletion later.
Do simple refcnt decrease, since driver in cleanup stage. This:
1) assumes that driver took proper internal parent unset action;
2) allows to avoid nested callbacks call and deadlock.

Fixes: d755598450 ("devlink: Allow setting parent node of rate objects")
Signed-off-by: Dmytro Linkin <dlinkin@nvidia.com>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-23 15:46:25 -07:00
Kuniyuki Iwashima
55d444b310 tcp: Add stats for socket migration.
This commit adds two stats for the socket migration feature to evaluate the
effectiveness: LINUX_MIB_TCPMIGRATEREQ(SUCCESS|FAILURE).

If the migration fails because of the own_req race in receiving ACK and
sending SYN+ACK paths, we do not increment the failure stat. Then another
CPU is responsible for the req.

Link: https://lore.kernel.org/bpf/CAK6E8=cgFKuGecTzSCSQ8z3YJ_163C0uwO9yRvfDSE7vOe9mJA@mail.gmail.com/
Suggested-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.co.jp>
Acked-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-23 12:56:08 -07:00
David S. Miller
fe87797bf2 mlx5-net-next-2021-06-22
1) Various minor cleanups and fixes from net-next branch
 2) Optimize mlx5 feature check on tx and
    a fix to allow Vxlan with Ipsec offloads
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Merge tag 'mlx5-net-next-2021-06-22' of git://git.kernel.org/pub/scm/linux/kernel/git/saeed/linux

Saeed Mahameed says:

====================
mlx5-net-next-2021-06-22

1) Various minor cleanups and fixes from net-next branch
2) Optimize mlx5 feature check on tx and
   a fix to allow Vxlan with Ipsec offloads
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-23 12:48:07 -07:00
David S. Miller
a7b62112f0 Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf-next
Pablo Neira Ayuso says:

====================
Netfilter updates for net-next

The following patchset contains Netfilter updates for net-next:

1) Skip non-SCTP packets in the new SCTP chunk support for nft_exthdr,
   from Phil Sutter.

2) Simplify TCP option sanity check for TCP packets, also from Phil.

3) Add a new expression to store when the rule has been used last time.

4) Pass the hook state object to log function, from Florian Westphal.

5) Document the new sysctl knobs to tune the flowtable timeouts,
   from Oz Shlomo.

6) Fix snprintf error check in the new nfnetlink_hook infrastructure,
   from Dan Carpenter.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-23 12:31:28 -07:00
Yunsheng Lin
d3e0f57501 net: sched: remove qdisc->empty for lockless qdisc
As MISSED and DRAINING state are used to indicate a non-empty
qdisc, qdisc->empty is not longer needed, so remove it.

Acked-by: Jakub Kicinski <kuba@kernel.org>
Tested-by: Vladimir Oltean <vladimir.oltean@nxp.com> # flexcan
Signed-off-by: Yunsheng Lin <linyunsheng@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-23 12:17:35 -07:00
Yunsheng Lin
c4fef01ba4 net: sched: implement TCQ_F_CAN_BYPASS for lockless qdisc
Currently pfifo_fast has both TCQ_F_CAN_BYPASS and TCQ_F_NOLOCK
flag set, but queue discipline by-pass does not work for lockless
qdisc because skb is always enqueued to qdisc even when the qdisc
is empty, see __dev_xmit_skb().

This patch calls sch_direct_xmit() to transmit the skb directly
to the driver for empty lockless qdisc, which aviod enqueuing
and dequeuing operation.

As qdisc->empty is not reliable to indicate a empty qdisc because
there is a time window between enqueuing and setting qdisc->empty.
So we use the MISSED state added in commit a90c57f2ce ("net:
sched: fix packet stuck problem for lockless qdisc"), which
indicate there is lock contention, suggesting that it is better
not to do the qdisc bypass in order to avoid packet out of order
problem.

In order to make MISSED state reliable to indicate a empty qdisc,
we need to ensure that testing and clearing of MISSED state is
within the protection of qdisc->seqlock, only setting MISSED state
can be done without the protection of qdisc->seqlock. A MISSED
state testing is added without the protection of qdisc->seqlock to
aviod doing unnecessary spin_trylock() for contention case.

As the enqueuing is not within the protection of qdisc->seqlock,
there is still a potential data race as mentioned by Jakub [1]:

      thread1               thread2             thread3
qdisc_run_begin() # true
                        qdisc_run_begin(q)
                             set(MISSED)
pfifo_fast_dequeue
  clear(MISSED)
  # recheck the queue
qdisc_run_end()
                            enqueue skb1
                                             qdisc empty # true
                                          qdisc_run_begin() # true
                                          sch_direct_xmit() # skb2
                         qdisc_run_begin()
                            set(MISSED)

When above happens, skb1 enqueued by thread2 is transmited after
skb2 is transmited by thread3 because MISSED state setting and
enqueuing is not under the qdisc->seqlock. If qdisc bypass is
disabled, skb1 has better chance to be transmited quicker than
skb2.

This patch does not take care of the above data race, because we
view this as similar as below:
Even at the same time CPU1 and CPU2 write the skb to two socket
which both heading to the same qdisc, there is no guarantee that
which skb will hit the qdisc first, because there is a lot of
factor like interrupt/softirq/cache miss/scheduling afffecting
that.

There are below cases that need special handling:
1. When MISSED state is cleared before another round of dequeuing
   in pfifo_fast_dequeue(), and __qdisc_run() might not be able to
   dequeue all skb in one round and call __netif_schedule(), which
   might result in a non-empty qdisc without MISSED set. In order
   to avoid this, the MISSED state is set for lockless qdisc and
   __netif_schedule() will be called at the end of qdisc_run_end.

2. The MISSED state also need to be set for lockless qdisc instead
   of calling __netif_schedule() directly when requeuing a skb for
   a similar reason.

3. For netdev queue stopped case, the MISSED case need clearing
   while the netdev queue is stopped, otherwise there may be
   unnecessary __netif_schedule() calling. So a new DRAINING state
   is added to indicate this case, which also indicate a non-empty
   qdisc.

4. As there is already netif_xmit_frozen_or_stopped() checking in
   dequeue_skb() and sch_direct_xmit(), which are both within the
   protection of qdisc->seqlock, but the same checking in
   __dev_xmit_skb() is without the protection, which might cause
   empty indication of a lockless qdisc to be not reliable. So
   remove the checking in __dev_xmit_skb(), and the checking in
   the protection of qdisc->seqlock seems enough to avoid the cpu
   consumption problem for netdev queue stopped case.

1. https://lkml.org/lkml/2021/5/29/215

Acked-by: Jakub Kicinski <kuba@kernel.org>
Tested-by: Vladimir Oltean <vladimir.oltean@nxp.com> # flexcan
Signed-off-by: Yunsheng Lin <linyunsheng@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-23 12:17:35 -07:00
Huy Nguyen
fa4535238f net/xfrm: Add inner_ipproto into sec_path
The inner_ipproto saves the inner IP protocol of the plain
text packet. This allows vendor's IPsec feature making offload
decision at skb's features_check and configuring hardware at
ndo_start_xmit.

For example, ConnectX6-DX IPsec device needs the plaintext's
IP protocol to support partial checksum offload on
VXLAN/GENEVE packet over IPsec transport mode tunnel.

Signed-off-by: Raed Salem <raeds@nvidia.com>
Signed-off-by: Huy Nguyen <huyn@nvidia.com>
Cc: Steffen Klassert <steffen.klassert@secunet.com>
Acked-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>
2021-06-22 15:24:32 -07:00
Paolo Abeni
fde56eea01 mptcp: refine mptcp_cleanup_rbuf
The current cleanup rbuf tries a bit too hard to avoid acquiring
the subflow socket lock. We may end-up delaying the needed ack,
or skip acking a blocked subflow.

Address the above extending the conditions used to trigger the cleanup
to reflect more closely what TCP does and invoking tcp_cleanup_rbuf()
on all the active subflows.

Note that we can't replicate the exact tests implemented in
tcp_cleanup_rbuf(), as MPTCP lacks some of the required info - e.g.
ping-pong mode.

Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-22 14:36:01 -07:00
Geliang Tang
df377be387 mptcp: add deny_join_id0 in mptcp_options_received
This patch added a new flag named deny_join_id0 in struct
mptcp_options_received. Set it when MP_CAPABLE with the flag
MPTCP_CAP_DENYJOIN_ID0 is received.

Also add a new flag remote_deny_join_id0 in struct mptcp_pm_data. When the
flag deny_join_id0 is set, set this remote_deny_join_id0 flag.

In mptcp_pm_create_subflow_or_signal_addr, if the remote_deny_join_id0 flag
is set, and the remote address id is zero, stop this connection.

Suggested-by: Florian Westphal <fw@strlen.de>
Acked-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Geliang Tang <geliangtang@gmail.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-22 14:36:01 -07:00
Geliang Tang
bab6b88e05 mptcp: add allow_join_id0 in mptcp_out_options
This patch defined a new flag MPTCP_CAP_DENY_JOIN_ID0 for the third bit,
labeled "C" of the MP_CAPABLE option.

Add a new flag allow_join_id0 in struct mptcp_out_options. If this flag is
set, send out the MP_CAPABLE option with the flag MPTCP_CAP_DENY_JOIN_ID0.

Acked-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Geliang Tang <geliangtang@gmail.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-22 14:36:01 -07:00
Geliang Tang
d2f77960e5 mptcp: add sysctl allow_join_initial_addr_port
This patch added a new sysctl, named allow_join_initial_addr_port, to
control whether allow peers to send join requests to the IP address and
port number used by the initial subflow.

Suggested-by: Florian Westphal <fw@strlen.de>
Acked-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Geliang Tang <geliangtang@gmail.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-22 14:36:01 -07:00
Xin Long
9e47df005c sctp: process sctp over udp icmp err on sctp side
Previously, sctp over udp was using udp tunnel's icmp err process, which
only does sk lookup on sctp side. However for sctp's icmp error process,
there are more things to do, like syncing assoc pmtu/retransmit packets
for toobig type err, and starting proto_unreach_timer for unreach type
err etc.

Now after adding PLPMTUD, which also requires to process toobig type err
on sctp side. This patch is to process icmp err on sctp side by parsing
the type/code/info in .encap_err_lookup and call sctp's icmp processing
functions. Note as the 'redirect' err process needs to know the outer
ip(v6) header's, we have to leave it to udp(v6)_err to handle it.

Signed-off-by: Xin Long <lucien.xin@gmail.com>
Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-22 11:28:52 -07:00
Xin Long
d83060759a sctp: extract sctp_v4_err_handle function from sctp_v4_err
This patch is to extract sctp_v4_err_handle() from sctp_v4_err() to
only handle the icmp err after the sock lookup, and it also makes
the code clearer.

sctp_v4_err_handle() will be used in sctp over udp's err handling
in the following patch.

Signed-off-by: Xin Long <lucien.xin@gmail.com>
Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-22 11:28:52 -07:00
Xin Long
f6549bd37b sctp: extract sctp_v6_err_handle function from sctp_v6_err
This patch is to extract sctp_v6_err_handle() from sctp_v6_err() to
only handle the icmp err after the sock lookup, and it also makes
the code clearer.

sctp_v6_err_handle() will be used in sctp over udp's err handling
in the following patch.

Signed-off-by: Xin Long <lucien.xin@gmail.com>
Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-22 11:28:52 -07:00
Xin Long
237a6a2e31 sctp: remove the unessessary hold for idev in sctp_v6_err
Same as in tcp_v6_err() and __udp6_lib_err(), there's no need to
hold idev in sctp_v6_err(), so just call __in6_dev_get() instead.

Signed-off-by: Xin Long <lucien.xin@gmail.com>
Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-22 11:28:52 -07:00
Xin Long
7307e4fa4d sctp: enable PLPMTUD when the transport is ready
sctp_transport_pl_reset() is called whenever any of these 3 members in
transport is changed:

  - probe_interval
  - param_flags & SPP_PMTUD_ENABLE
  - state == ACTIVE

If all are true, start the PLPMTUD when it's not yet started. If any of
these is false, stop the PLPMTUD when it's already running.

sctp_transport_pl_update() is called when the transport dst has changed.
It will restart the PLPMTUD probe. Again, the pathmtu won't change but
use the dst's mtu until the Search phase is done.

Note that after using PLPMTUD, the pathmtu is only initialized with the
dst mtu when the transport dst changes. At other time it is updated by
pl.pmtu. So sctp_transport_pmtu_check() will be called only when PLPMTUD
is disabled in sctp_packet_config().

After this patch, the PLPMTUD feature from RFC8899 will be activated
and can be used by users.

Signed-off-by: Xin Long <lucien.xin@gmail.com>
Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-22 11:28:52 -07:00
Xin Long
8369640831 sctp: do state transition when receiving an icmp TOOBIG packet
PLPMTUD will short-circuit the old process for icmp TOOBIG packets.
This part is described in rfc8899#section-4.6.2 (PL_PTB_SIZE =
PTB_SIZE - other_headers_len). Note that from rfc8899#section-5.2
State Machine, each case below is for some specific states only:

  a) PL_PTB_SIZE < MIN_PLPMTU || PL_PTB_SIZE >= PROBED_SIZE,
     discard it, for any state

  b) MIN_PLPMTU < PL_PTB_SIZE < BASE_PLPMTU,
     Base -> Error, for Base state

  c) BASE_PLPMTU <= PL_PTB_SIZE < PLPMTU,
     Search -> Base or Complete -> Base, for Search and Complete states.

  d) PLPMTU < PL_PTB_SIZE < PROBED_SIZE,
     set pl.probe_size to PL_PTB_SIZE then verify it, for Search state.

The most important one is case d), which will help find the optimal
fast during searching. Like when pathmtu = 1392 for SCTP over IPv4,
the search will be (20 is iphdr_len):

  1. probe with 1200 - 20
  2. probe with 1232 - 20
  3. probe with 1264 - 20
  ...
  7. probe with 1388 - 20
  8. probe with 1420 - 20

When sending the probe with 1420 - 20, TOOBIG may come with PL_PTB_SIZE =
1392 - 20. Then it matches case d), and saves some rounds to try with the
1392 - 20 probe. But of course, PLPMTUD doesn't trust TOOBIG packets, and
it will go back to the common searching once the probe with the new size
can't be verified.

Signed-off-by: Xin Long <lucien.xin@gmail.com>
Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-22 11:28:52 -07:00
Xin Long
b87641aff9 sctp: do state transition when a probe succeeds on HB ACK recv path
As described in rfc8899#section-5.2, when a probe succeeds, there might
be the following state transitions:

  - Base -> Search, occurs when probe succeeds with BASE_PLPMTU,
    pl.pmtu is not changing,
    pl.probe_size increases by SCTP_PL_BIG_STEP,

  - Error -> Search, occurs when probe succeeds with BASE_PLPMTU,
    pl.pmtu is changed from SCTP_MIN_PLPMTU to SCTP_BASE_PLPMTU,
    pl.probe_size increases by SCTP_PL_BIG_STEP.

  - Search -> Search Complete, occurs when probe succeeds with the probe
    size SCTP_MAX_PLPMTU less than pl.probe_high,
    pl.pmtu is not changing, but update *pathmtu* with it,
    pl.probe_size is set back to pl.pmtu to double check it.

  - Search Complete -> Search, occurs when probe succeeds with the probe
    size equal to pl.pmtu,
    pl.pmtu is not changing,
    pl.probe_size increases by SCTP_PL_MIN_STEP.

So search process can be described as:

 1. When it just enters 'Search' state, *pathmtu* is not updated with
    pl.pmtu, and probe_size increases by a big step (SCTP_PL_BIG_STEP)
    each round.

 2. Until pl.probe_high is set when a probe fails, and probe_size
    decreases back to pl.pmtu, as described in the last patch.

 3. When the probe with the new size succeeds, probe_size changes to
    increase by a small step (SCTP_PL_MIN_STEP) due to pl.probe_high
    is set.

 4. Until probe_size is next to pl.probe_high, the searching finishes and
    it goes to 'Complete' state and updates *pathmtu* with pl.pmtu, and
    then probe_size is set to pl.pmtu to confirm by once more probe.

 5. This probe occurs after "30 * probe_inteval", a much longer time than
    that in Search state. Once it is done it goes to 'Search' state again
    with probe_size increased by SCTP_PL_MIN_STEP.

As we can see above, during the searching, pl.pmtu changes while *pathmtu*
doesn't. *pathmtu* is only updated when the search finishes by which it
gets an optimal value for it. A big step is used at the beginning until
it gets close to the optimal value, then it changes to a small step until
it has this optimal value.

The small step is also used in 'Complete' until it goes to 'Search' state
again and the probe with 'pmtu + the small step' succeeds, which means a
higher size could be used. Then probe_size changes to increase by a big
step again until it gets close to the next optimal value.

Note that anytime when black hole is detected, it goes directly to 'Base'
state with pl.pmtu set to SCTP_BASE_PLPMTU, as described in the last patch.

Signed-off-by: Xin Long <lucien.xin@gmail.com>
Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-22 11:28:52 -07:00
Xin Long
1dc68c1945 sctp: do state transition when PROBE_COUNT == MAX_PROBES on HB send path
The state transition is described in rfc8899#section-5.2,
PROBE_COUNT == MAX_PROBES means the probe fails for MAX times, and the
state transition includes:

  - Base -> Error, occurs when BASE_PLPMTU Confirmation Fails,
    pl.pmtu is set to SCTP_MIN_PLPMTU,
    probe_size is still SCTP_BASE_PLPMTU;

  - Search -> Base, occurs when Black Hole Detected,
    pl.pmtu is set to SCTP_BASE_PLPMTU,
    probe_size is set back to SCTP_BASE_PLPMTU;

  - Search Complete -> Base, occurs when Black Hole Detected
    pl.pmtu is set to SCTP_BASE_PLPMTU,
    probe_size is set back to SCTP_BASE_PLPMTU;

Note a black hole is encountered when a sender is unaware that packets
are not being delivered to the destination endpoint. So it includes the
probe failures with equal probe_size to pl.pmtu, and definitely not
include that with greater probe_size than pl.pmtu. The later one is the
normal probe failure where probe_size should decrease back to pl.pmtu
and pl.probe_high is set.  pl.probe_high would be used on HB ACK recv
path in the next patch.

Signed-off-by: Xin Long <lucien.xin@gmail.com>
Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-22 11:28:52 -07:00
Xin Long
fe59379b9a sctp: do the basic send and recv for PLPMTUD probe
This patch does exactly what rfc8899#section-6.2.1.2 says:

   The SCTP sender needs to be able to determine the total size of a
   probe packet.  The HEARTBEAT chunk could carry a Heartbeat
   Information parameter that includes, besides the information
   suggested in [RFC4960], the probe size to help an implementation
   associate a HEARTBEAT ACK with the size of probe that was sent.  The
   sender could also use other methods, such as sending a nonce and
   verifying the information returned also contains the corresponding
   nonce.  The length of the PAD chunk is computed by reducing the
   probing size by the size of the SCTP common header and the HEARTBEAT
   chunk.

Note that HB ACK chunk will carry back whatever HB chunk carried, including
the probe_size we put it in; We also check hbinfo->probe_size in the HB ACK
against link->pl.probe_size to validate this HB ACK chunk.

v1->v2:
  - Remove the unused 'sp' and add static for sctp_packet_bundle_pad().

Signed-off-by: Xin Long <lucien.xin@gmail.com>
Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-22 11:28:52 -07:00
Xin Long
92548ec2f1 sctp: add the probe timer in transport for PLPMTUD
There are 3 timers described in rfc8899#section-5.1.1:

  PROBE_TIMER, PMTU_RAISE_TIMER, CONFIRMATION_TIMER

This patches adds a 'probe_timer' in transport, and it works as either
PROBE_TIMER or PMTU_RAISE_TIMER. At most time, it works as PROBE_TIMER
and expires every a 'probe_interval' time to send the HB probe packet.
When transport pl enters COMPLETE state, it works as PMTU_RAISE_TIMER
and expires in 'probe_interval * 30' time to go back to SEARCH state
and do searching again.

SCTP HB is an acknowledged packet, CONFIRMATION_TIMER is not needed.

The timer will start when transport pl enters BASE state and stop
when it enters DISABLED state.

Signed-off-by: Xin Long <lucien.xin@gmail.com>
Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-22 11:28:52 -07:00
Xin Long
3190b649b4 sctp: add SCTP_PLPMTUD_PROBE_INTERVAL sockopt for sock/asoc/transport
With this socket option, users can change probe_interval for
a transport, asoc or sock after it's created.

Note that if the change is for an asoc, also apply the change
to each transport in this asoc.

Signed-off-by: Xin Long <lucien.xin@gmail.com>
Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-22 11:28:51 -07:00
Xin Long
d1e462a7a5 sctp: add probe_interval in sysctl and sock/asoc/transport
PLPMTUD can be enabled by doing 'sysctl -w net.sctp.probe_interval=n'.
'n' is the interval for PLPMTUD probe timer in milliseconds, and it
can't be less than 5000 if it's not 0.

All asoc/transport's PLPMTUD in a new socket will be enabled by default.

Signed-off-by: Xin Long <lucien.xin@gmail.com>
Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-22 11:28:51 -07:00
Xin Long
745a32117b sctp: add pad chunk and its make function and event table
This chunk is defined in rfc4820#section-3, and used to pad an
SCTP packet. The receiver must discard this chunk and continue
processing the rest of the chunks in the packet.

Add it now, as it will be bundled with a heartbeat chunk to probe
pmtu in the following patches.

Signed-off-by: Xin Long <lucien.xin@gmail.com>
Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-22 11:28:51 -07:00
Aaron Conole
c4ab7b56be openvswitch: add trace points
This makes openvswitch module use the event tracing framework
to log the upcall interface and action execution pipeline.  When
using openvswitch as the packet forwarding engine, some types of
debugging are made possible simply by using the ovs-vswitchd's
ofproto/trace command.  However, such a command has some
limitations:

  1. When trying to trace packets that go through the CT action,
     the state of the packet can't be determined, and probably
     would be potentially wrong.

  2. Deducing problem packets can sometimes be difficult as well
     even if many of the flows are known

  3. It's possible to use the openvswitch module even without
     the ovs-vswitchd (although, not common use).

Introduce the event tracing points here to make it possible for
working through these problems in kernel space.  The style is
copied from the mac80211 driver-trace / trace code for
consistency - this creates some checkpatch splats, but the
official 'guide' for adding tracepoints, as well as the existing
examples all add the same splats so it seems acceptable.

Signed-off-by: Aaron Conole <aconole@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-22 10:47:32 -07:00
Ido Schimmel
88f9a87afe ethtool: Validate module EEPROM offset as part of policy
Validate the offset to read from module EEPROM as part of the netlink
policy and remove the corresponding check from the code.

This also makes it possible to query the offset range from user space:

 $ genl ctrl policy name ethtool
 ...
 ID: 0x14  policy[32]:attr[2]: type=U32 range:[0,255]
 ...

Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-22 10:40:54 -07:00
Ido Schimmel
0dc7dd02ba ethtool: Validate module EEPROM length as part of policy
Validate the number of bytes to read from the module EEPROM as part of
the netlink policy and remove the corresponding check from the code.

This also makes it possible to query the length range from user space:

 $ genl ctrl policy name ethtool
 ...
 ID: 0x14  policy[32]:attr[3]: type=U32 range:[1,128]
 ...

Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-22 10:40:54 -07:00
Ido Schimmel
f5fe211d13 ethtool: Decrease size of module EEPROM get policy array
The 'ETHTOOL_A_MODULE_EEPROM_DATA' attribute is not part of the get
request.

Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-22 10:40:54 -07:00
gushengxian
98534fce52 bridge: cfm: remove redundant return
Return statements are not needed in Void function.

Signed-off-by: gushengxian <gushengxian@yulong.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-22 10:35:15 -07:00
Paolo Abeni
06285da96a mptcp: add MIB counter for invalid mapping
Account this exceptional events for better introspection.

Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-22 09:57:45 -07:00
Paolo Abeni
8cfc47fc2e mptcp: drop redundant test in move_skbs_to_msk()
Currently we check the msk state to avoid enqueuing new
skbs at msk shutdown time.

Such test is racy - as we can't acquire the msk socket lock -
and useless, as the caller already checked the subflow
field 'disposable', covering the same scenario in a race
free manner - read and updated under the ssk socket lock.

Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-22 09:57:45 -07:00
Paolo Abeni
3c90e377a1 mptcp: don't clear MPTCP_DATA_READY in sk_wait_event()
If we don't flush entirely the receive queue, we need set
again such bit later. We can simply avoid clearing it.

Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-22 09:57:45 -07:00
Paolo Abeni
75e908c336 mptcp: use fast lock for subflows when possible
There are a bunch of callsite where the ssk socket
lock is acquired using the full-blown version eligible for
the fast variant. Let's move to the latter.

Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-22 09:57:45 -07:00
Paolo Abeni
8ce568ed06 mptcp: drop tx skb cache
The mentioned cache was introduced to reduce the number of skb
allocation in atomic context, but the required complexity is
excessive.

This change remove the mentioned cache.

Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-22 09:57:45 -07:00
Eric Dumazet
64295f0d01 virtio/vsock: avoid NULL deref in virtio_transport_seqpacket_allow()
Make sure the_virtio_vsock is not NULL before dereferencing it.

general protection fault, probably for non-canonical address 0xdffffc0000000071: 0000 [#1] PREEMPT SMP KASAN
KASAN: null-ptr-deref in range [0x0000000000000388-0x000000000000038f]
CPU: 0 PID: 8452 Comm: syz-executor406 Not tainted 5.13.0-rc6-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:virtio_transport_seqpacket_allow+0xbf/0x210 net/vmw_vsock/virtio_transport.c:503
Code: e8 c6 d9 ab f8 84 db 0f 84 0f 01 00 00 e8 09 d3 ab f8 48 8d bd 88 03 00 00 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <0f> b6 04 02 84 c0 74 06 0f 8e 2a 01 00 00 44 0f b6 a5 88 03 00 00
RSP: 0018:ffffc90003757c18 EFLAGS: 00010206
RAX: dffffc0000000000 RBX: 0000000000000001 RCX: 0000000000000000
RDX: 0000000000000071 RSI: ffffffff88c908e7 RDI: 0000000000000388
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: ffffffff88c90a06 R11: 0000000000000000 R12: 0000000000000000
R13: ffffffff88c90840 R14: 0000000000000000 R15: 0000000000000001
FS:  0000000001bee300(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000020000082 CR3: 000000002847e000 CR4: 00000000001506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 vsock_assign_transport+0x575/0x700 net/vmw_vsock/af_vsock.c:490
 vsock_connect+0x200/0xc00 net/vmw_vsock/af_vsock.c:1337
 __sys_connect_file+0x155/0x1a0 net/socket.c:1824
 __sys_connect+0x161/0x190 net/socket.c:1841
 __do_sys_connect net/socket.c:1851 [inline]
 __se_sys_connect net/socket.c:1848 [inline]
 __x64_sys_connect+0x6f/0xb0 net/socket.c:1848
 do_syscall_64+0x3a/0xb0 arch/x86/entry/common.c:47
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x43ee69
Code: 28 c3 e8 2a 14 00 00 66 2e 0f 1f 84 00 00 00 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 c0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffd49e7c788 EFLAGS: 00000246 ORIG_RAX: 000000000000002a
RAX: ffffffffffffffda RBX: 0000000000400488 RCX: 000000000043ee69
RDX: 0000000000000010 RSI: 0000000020000080 RDI: 0000000000000003
RBP: 0000000000402e50 R08: 0000000000000000 R09: 0000000000400488
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000402ee0
R13: 0000000000000000 R14: 00000000004ac018 R15: 0000000000400488

Fixes: 53efbba12c ("virtio/vsock: enable SEQPACKET for transport")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Arseny Krasnov <arseny.krasnov@kaspersky.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-22 09:49:37 -07:00
Boris Sukholitko
6d5516177d Revert "net/sched: cls_flower: Remove match on n_proto"
This reverts commit 0dca2c7404.

The commit in question breaks hardware offload of flower filters.

Quoting Vladimir Oltean <olteanv@gmail.com>:

 fl_hw_replace_filter() and fl_reoffload() create a struct
 flow_cls_offload with a rule->match.mask member derived from the mask
 of the software classifier: &f->mask->key - that same mask that is used
 for initializing the flow dissector keys, and the one from which Boris
 removed the basic.n_proto member because it was bothering him.

Reported-by: Vadym Kochan <vadym.kochan@plvision.eu>
Signed-off-by: Boris Sukholitko <boris.sukholitko@broadcom.com>
Reviewed-by: Vladimir Oltean <olteanv@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-21 14:46:36 -07:00
Yejune Deng
fe0bdbde07 net: add pf_family_names[] for protocol family
Modify the pr_info content from int to char * in sock_register() and
sock_unregister(), this looks more readable.

Fixed build error in ARCH=sparc64.

Signed-off-by: Yejune Deng <yejune.deng@gmail.com>
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-21 14:41:54 -07:00
Dan Carpenter
24610ed80d netfilter: nfnetlink_hook: fix check for snprintf() overflow
The kernel version of snprintf() can't return negatives.  The
"ret > (int)sizeof(sym)" check is off by one because and it should be
>=.  Finally, we need to set a negative error code.

Fixes: e2cf17d377 ("netfilter: add new hook nfnl subsystem")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2021-06-21 22:05:29 +02:00
Vladimir Oltean
f9bcdc362c net: dsa: remove cross-chip support from the MRP notifiers
With MRP hardware assist being supported only by the ocelot switch
family, which by design does not support cross-chip bridging, the
current match functions are at best a guess and have not been confirmed
in any way to do anything relevant in a multi-switch topology.

Drop the code and make the notifiers match only on the targeted switch
port.

Cc: Horatiu Vultur <horatiu.vultur@microchip.com>
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-21 12:50:20 -07:00
Vladimir Oltean
88faba20e2 net: dsa: targeted MTU notifiers should only match on one port
dsa_slave_change_mtu() calls dsa_port_mtu_change() twice:
- it sends a cross-chip notifier with the MTU of the CPU port which is
  used to update the DSA links.
- it sends one targeted MTU notifier which is supposed to only match the
  user port on which we are changing the MTU. The "propagate_upstream"
  variable is used here to bypass the cross-chip notifier system from
  switch.c

But due to a mistake, the second, targeted notifier matches not only on
the user port, but also on the DSA link which is a member of the same
switch, if that exists.

And because the DSA links of the entire dst were programmed in a
previous round to the largest_mtu via a "propagate_upstream == true"
notification, then the dsa_port_mtu_change(propagate_upstream == false)
call that is immediately upcoming will break the MTU on the one DSA link
which is chip-wise local to the dp whose MTU is changing right now.

Example given this daisy chain topology:

   sw0p0     sw0p1     sw0p2     sw0p3     sw0p4
[  cpu  ] [  user ] [  user ] [  dsa  ] [  user ]
[   x   ] [       ] [       ] [   x   ] [       ]
                                  |
                                  +---------+
                                            |
   sw1p0     sw1p1     sw1p2     sw1p3     sw1p4
[  user ] [  user ] [  user ] [  dsa  ] [  dsa  ]
[       ] [       ] [       ] [       ] [   x   ]

ip link set sw0p1 mtu 9000
ip link set sw1p1 mtu 9000 # at this stage, sw0p1 and sw1p1 can talk
                           # to one another using jumbo frames
ip link set sw0p2 mtu 1500 # this programs the sw0p3 DSA link first to
                           # the largest_mtu of 9000, then reprograms it to
                           # 1500 with the "propagate_upstream == false"
                           # notifier, breaking communication between
                           # sw0p1 and sw1p1

To escape from this situation, make the targeted match really match on a
single port - the user port, and rename the "propagate_upstream"
variable to "targeted_match" to clarify the intention and avoid future
issues.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-21 12:50:20 -07:00
Vladimir Oltean
4e4ab79500 net: dsa: calculate the largest_mtu across all ports in the tree
If we have a cross-chip topology like this:

   sw0p0     sw0p1     sw0p2     sw0p3     sw0p4
[  cpu  ] [  user ] [  user ] [  dsa  ] [  user ]
                                  |
                                  +---------+
                                            |
   sw1p0     sw1p1     sw1p2     sw1p3     sw1p4
[  user ] [  user ] [  user ] [  dsa  ] [  dsa  ]

and we issue the following commands:

1. ip link set sw0p1 mtu 1700
2. ip link set sw1p1 mtu 1600

we notice the following happening:

Command 1. emits a non-targeted MTU notifier for the CPU port (sw0p0)
with the largest_mtu calculated across switch 0, of 1700. This matches
sw0p0, sw0p3 and sw1p4 (all CPU ports and DSA links).
Then, it emits a targeted MTU notifier for the user port (sw0p1), again
with MTU 1700 (this doesn't matter).

Command 2. emits a non-targeted MTU notifier for the CPU port (sw0p0)
with the largest_mtu calculated across switch 1, of 1600. This matches
the same group of ports as above, and decreases the MTU for the CPU port
and the DSA links from 1700 to 1600.

As a result, the sw0p1 user port can no longer communicate with its CPU
port at MTU 1700.

To address this, we should calculate the largest_mtu across all switches
that may share a CPU port, and only emit MTU notifiers with that value.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-21 12:50:20 -07:00
Vladimir Oltean
abd49535c3 net: dsa: execute dsa_switch_mdb_add only for routing port in cross-chip topologies
Currently, the notifier for adding a multicast MAC address matches on
the targeted port and on all DSA links in the system, be they upstream
or downstream links.

This leads to a considerable amount of useless traffic.

Consider this daisy chain topology, and a MDB add notifier emitted on
sw0p0. It matches on sw0p0, sw0p3, sw1p3 and sw2p4.

   sw0p0     sw0p1     sw0p2     sw0p3     sw0p4
[  user ] [  user ] [  user ] [  dsa  ] [  cpu  ]
[   x   ] [       ] [       ] [   x   ] [       ]
                                  |
                                  +---------+
                                            |
   sw1p0     sw1p1     sw1p2     sw1p3     sw1p4
[  user ] [  user ] [  user ] [  dsa  ] [  dsa  ]
[       ] [       ] [       ] [   x   ] [   x   ]
                                  |
                                  +---------+
                                            |
   sw2p0     sw2p1     sw2p2     sw2p3     sw2p4
[  user ] [  user ] [  user ] [  user ] [  dsa  ]
[       ] [       ] [       ] [       ] [   x   ]

But switch 0 has no reason to send the multicast traffic for that MAC
address on sw0p3, which is how it reaches switches 1 and 2. Those
switches don't expect, according to the user configuration, to receive
this multicast address from switch 1, and they will drop it anyway,
because the only valid destination is the port they received it on.
They only need to configure themselves to deliver that multicast address
_towards_ switch 1, where the MDB entry is installed.

Similarly, switch 1 should not send this multicast traffic towards
sw1p3, because that is how it reaches switch 2.

With this change, the heat map for this MDB notifier changes as follows:

   sw0p0     sw0p1     sw0p2     sw0p3     sw0p4
[  user ] [  user ] [  user ] [  dsa  ] [  cpu  ]
[   x   ] [       ] [       ] [       ] [       ]
                                  |
                                  +---------+
                                            |
   sw1p0     sw1p1     sw1p2     sw1p3     sw1p4
[  user ] [  user ] [  user ] [  dsa  ] [  dsa  ]
[       ] [       ] [       ] [       ] [   x   ]
                                  |
                                  +---------+
                                            |
   sw2p0     sw2p1     sw2p2     sw2p3     sw2p4
[  user ] [  user ] [  user ] [  user ] [  dsa  ]
[       ] [       ] [       ] [       ] [   x   ]

Now the mdb notifier behaves the same as the fdb notifier.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-21 12:50:20 -07:00