Commit Graph

1003 Commits

Author SHA1 Message Date
Eugene Syromiatnikov ff8292bb10 mptcp: correct MPTCP_SUBFLOW_ATTR_SSN_OFFSET reserved size
[ Upstream commit 655111b838cdabdb604f3625a9ff08c5eedb11da ]

ssn_offset field is u32 and is placed into the netlink response with
nla_put_u32(), but only 2 bytes are reserved for the attribute payload
in subflow_get_info_size() (even though it makes no difference
in the end, as it is aligned up to 4 bytes).  Supply the correct
argument to the relevant nla_total_size() call to make it less
confusing.

Fixes: 5147dfb508 ("mptcp: allow dumping subflow context to userspace")
Signed-off-by: Eugene Syromiatnikov <esyr@redhat.com>
Reviewed-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Link: https://patch.msgid.link/20240812065024.GA19719@asgard.redhat.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-08-29 17:33:19 +02:00
Matthieu Baerts (NGI0) 64815ba158 mptcp: pm: do not ignore 'subflow' if 'signal' flag is also set
commit 85df533a787bf07bf4367ce2a02b822ff1fba1a3 upstream.

Up to the 'Fixes' commit, having an endpoint with both the 'signal' and
'subflow' flags, resulted in the creation of a subflow and an address
announcement using the address linked to this endpoint. After this
commit, only the address announcement was done, ignoring the 'subflow'
flag.

That's because the same bitmap is used for the two flags. It is OK to
keep this single bitmap, the already selected local endpoint simply have
to be re-used, but not via select_local_address() not to look at the
just modified bitmap.

Note that it is unusual to set the two flags together: creating a new
subflow using a new local address will implicitly advertise it to the
other peer. So in theory, no need to advertise it explicitly as well.
Maybe there are use-cases -- the subflow might not reach the other peer
that way, we can ask the other peer to try initiating the new subflow
without delay -- or very likely the user is confused, and put both flags
"just to be sure at least the right one is set". Still, if it is
allowed, the kernel should do what has been asked: using this endpoint
to announce the address and to create a new subflow from it.

An alternative is to forbid the use of the two flags together, but
that's probably too late, there are maybe use-cases, and it was working
before. This patch will avoid people complaining subflows are not
created using the endpoint they added with the 'subflow' and 'signal'
flag.

Note that with the current patch, the subflow might not be created in
some corner cases, e.g. if the 'subflows' limit was reached when sending
the ADD_ADDR, but changed later on. It is probably not worth splitting
id_avail_bitmap per target ('signal', 'subflow'), which will add another
large field to the msk "just" to track (again) endpoints. Anyway,
currently when the limits are changed, the kernel doesn't check if new
subflows can be created or removed, because we would need to keep track
of the received ADD_ADDR, and more. It sounds OK to assume that the
limits should be properly configured before establishing new
connections.

Fixes: 86e39e0448 ("mptcp: keep track of local endpoint still available for each msk")
Cc: stable@vger.kernel.org
Suggested-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Link: https://patch.msgid.link/20240731-upstream-net-20240731-mptcp-endp-subflow-signal-v1-5-c8a9b036493b@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-08-14 13:59:04 +02:00
Matthieu Baerts (NGI0) 9a4a4c0b8e mptcp: pm: don't try to create sf if alloc failed
commit cd7c957f936f8cb80d03e5152f4013aae65bd986 upstream.

It sounds better to avoid wasting cycles and / or put extreme memory
pressure on the system by trying to create new subflows if it was not
possible to add a new item in the announce list.

While at it, a warning is now printed if the entry was already in the
list as it should not happen with the in-kernel path-manager. With this
PM, mptcp_pm_alloc_anno_list() should only fail in case of memory
pressure.

Fixes: b6c0838086 ("mptcp: remove addr and subflow in PM netlink")
Cc: stable@vger.kernel.org
Suggested-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Link: https://patch.msgid.link/20240731-upstream-net-20240731-mptcp-endp-subflow-signal-v1-4-c8a9b036493b@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-08-14 13:59:03 +02:00
Matthieu Baerts (NGI0) 432535f52e mptcp: pm: reduce indentation blocks
commit c95eb32ced823a00be62202b43966b07b2f20b7f upstream.

That will simplify the following commits.

No functional changes intended.

Suggested-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Link: https://patch.msgid.link/20240731-upstream-net-20240731-mptcp-endp-subflow-signal-v1-3-c8a9b036493b@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Stable-dep-of: cd7c957f936f ("mptcp: pm: don't try to create sf if alloc failed")
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-08-14 13:59:03 +02:00
Matthieu Baerts (NGI0) d4c67071f4 mptcp: pm: deny endp with signal + subflow + port
commit 8af1f11865f259c882cce71d32f85ee9004e2660 upstream.

As mentioned in the 'Fixes' commit, the port flag is only supported by
the 'signal' flag, and not by the 'subflow' one. Then if both the
'signal' and 'subflow' flags are set, the problem is the same: the
feature cannot work with the 'subflow' flag.

Technically, if both the 'signal' and 'subflow' flags are set, it will
be possible to create the listening socket, but not to establish a
subflow using this source port. So better to explicitly deny it, not to
create some confusions because the expected behaviour is not possible.

Fixes: 09f12c3ab7 ("mptcp: allow to use port and non-signal in set_flags")
Cc: stable@vger.kernel.org
Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Link: https://patch.msgid.link/20240731-upstream-net-20240731-mptcp-endp-subflow-signal-v1-2-c8a9b036493b@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-08-14 13:59:02 +02:00
Matthieu Baerts (NGI0) fff9b9208c mptcp: pm: fix backup support in signal endpoints
commit 6834097fc38c5416701c793da94558cea49c0a1f upstream.

There was a support for signal endpoints, but only when the endpoint's
flag was changed during a connection. If an endpoint with the signal and
backup was already present, the MP_JOIN reply was not containing the
backup flag as expected.

That's confusing to have this inconsistent behaviour. On the other hand,
the infrastructure to set the backup flag in the SYN + ACK + MP_JOIN was
already there, it was just never set before. Now when requesting the
local ID from the path-manager, the backup status is also requested.

Note that when the userspace PM is used, the backup flag can be set if
the local address was already used before with a backup flag, e.g. if
the address was announced with the 'backup' flag, or a subflow was
created with the 'backup' flag.

Fixes: 4596a2c1b7 ("mptcp: allow creating non-backup subflows")
Cc: stable@vger.kernel.org
Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/507
Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
[ Conflicts in pm_userspace.c because the context has changed in commit
  1e07938e29c5 ("net: mptcp: rename netlink handlers to
  mptcp_pm_nl_<blah>_{doit,dumpit}") which is not in this version. This
  commit is unrelated to this modification.
  Conflicts in protocol.h because the context has changed in commit
  9ae7846c4b6b ("mptcp: dump addrs in userspace pm list") which is not
  in this version. This commit is unrelated to this modification. ]
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-08-14 13:59:01 +02:00
Matthieu Baerts (NGI0) 07bb418cb0 mptcp: fully established after ADD_ADDR echo on MPJ
commit d67c5649c1541dc93f202eeffc6f49220a4ed71d upstream.

Before this patch, receiving an ADD_ADDR echo on the just connected
MP_JOIN subflow -- initiator side, after the MP_JOIN 3WHS -- was
resulting in an MP_RESET. That's because only ACKs with a DSS or
ADD_ADDRs without the echo bit were allowed.

Not allowing the ADD_ADDR echo after an MP_CAPABLE 3WHS makes sense, as
we are not supposed to send an ADD_ADDR before because it requires to be
in full established mode first. For the MP_JOIN 3WHS, that's different:
the ADD_ADDR can be sent on a previous subflow, and the ADD_ADDR echo
can be received on the recently created one. The other peer will already
be in fully established, so it is allowed to send that.

We can then relax the conditions here to accept the ADD_ADDR echo for
MPJ subflows.

Fixes: 67b12f792d ("mptcp: full fully established support after ADD_ADDR")
Cc: stable@vger.kernel.org
Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Link: https://patch.msgid.link/20240731-upstream-net-20240731-mptcp-endp-subflow-signal-v1-1-c8a9b036493b@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-08-14 13:59:01 +02:00
Paolo Abeni ee3c845787 mptcp: prevent BPF accessing lowat from a subflow socket.
commit fcf4692fa39e86a590c14a4af2de704e1d20a3b5 upstream.

Alexei reported the following splat:

 WARNING: CPU: 32 PID: 3276 at net/mptcp/subflow.c:1430 subflow_data_ready+0x147/0x1c0
 Modules linked in: dummy bpf_testmod(O) [last unloaded: bpf_test_no_cfi(O)]
 CPU: 32 PID: 3276 Comm: test_progs Tainted: GO       6.8.0-12873-g2c43c33bfd23
 Call Trace:
  <TASK>
  mptcp_set_rcvlowat+0x79/0x1d0
  sk_setsockopt+0x6c0/0x1540
  __bpf_setsockopt+0x6f/0x90
  bpf_sock_ops_setsockopt+0x3c/0x90
  bpf_prog_509ce5db2c7f9981_bpf_test_sockopt_int+0xb4/0x11b
  bpf_prog_dce07e362d941d2b_bpf_test_socket_sockopt+0x12b/0x132
  bpf_prog_348c9b5faaf10092_skops_sockopt+0x954/0xe86
  __cgroup_bpf_run_filter_sock_ops+0xbc/0x250
  tcp_connect+0x879/0x1160
  tcp_v6_connect+0x50c/0x870
  mptcp_connect+0x129/0x280
  __inet_stream_connect+0xce/0x370
  inet_stream_connect+0x36/0x50
  bpf_trampoline_6442491565+0x49/0xef
  inet_stream_connect+0x5/0x50
  __sys_connect+0x63/0x90
  __x64_sys_connect+0x14/0x20

The root cause of the issue is that bpf allows accessing mptcp-level
proto_ops from a tcp subflow scope.

Fix the issue detecting the problematic call and preventing any action.

Reported-by: Alexei Starovoitov <alexei.starovoitov@gmail.com>
Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/482
Fixes: 5684ab1a0eff ("mptcp: give rcvlowat some love")
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Mat Martineau <martineau@kernel.org>
Reviewed-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Link: https://lore.kernel.org/r/d8cb7d8476d66cb0812a6e29cd1e626869d9d53e.1711738080.git.pabeni@redhat.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-08-11 12:47:28 +02:00
Paolo Abeni bf39cfc023 mptcp: fix duplicate data handling
commit 68cc924729ffcfe90d0383177192030a9aeb2ee4 upstream.

When a subflow receives and discards duplicate data, the mptcp
stack assumes that the consumed offset inside the current skb is
zero.

With multiple subflows receiving data simultaneously such assertion
does not held true. As a result the subflow-level copied_seq will
be incorrectly increased and later on the same subflow will observe
a bad mapping, leading to subflow reset.

Address the issue taking into account the skb consumed offset in
mptcp_subflow_discard_data().

Fixes: 04e4cd4f7c ("mptcp: cleanup mptcp_subflow_discard_data()")
Cc: stable@vger.kernel.org
Link: https://github.com/multipath-tcp/mptcp_net-next/issues/501
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-08-11 12:47:27 +02:00
Matthieu Baerts (NGI0) bd1d1fc4bc mptcp: pm: only set request_bkup flag when sending MP_PRIO
commit 4258b94831bb7ff28ab80e3c8d94db37db930728 upstream.

The 'backup' flag from mptcp_subflow_context structure is supposed to be
set only when the other peer flagged a subflow as backup, not the
opposite.

Fixes: 067065422f ("mptcp: add the outgoing MP_PRIO support")
Cc: stable@vger.kernel.org
Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-08-11 12:47:27 +02:00
Paolo Abeni 19bf32929b mptcp: fix bad RCVPRUNED mib accounting
commit 0a567c2a10033bf04ed618368d179bce6977984b upstream.

Since its introduction, the mentioned MIB accounted for the wrong
event: wake-up being skipped as not-needed on some edge condition
instead of incoming skb being dropped after landing in the (subflow)
receive queue.

Move the increment in the correct location.

Fixes: ce599c5163 ("mptcp: properly account bulk freed memory")
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-08-11 12:47:27 +02:00
Matthieu Baerts (NGI0) 6721cbaa04 mptcp: mib: count MPJ with backup flag
commit 4dde0d72ccec500c60c798e036b852e013d6e124 upstream.

Without such counters, it is difficult to easily debug issues with MPJ
not having the backup flags on production servers.

This is not strictly a fix, but it eases to validate the following
patches without requiring to take packet traces, to query ongoing
connections with Netlink with admin permissions, or to guess by looking
at the behaviour of the packet scheduler. Also, the modification is self
contained, isolated, well controlled, and the increments are done just
after others, there from the beginning. It looks then safe, and helpful
to backport this.

Fixes: 4596a2c1b7 ("mptcp: allow creating non-backup subflows")
Cc: stable@vger.kernel.org
Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-08-11 12:47:27 +02:00
Paolo Abeni e680e635ed mptcp: fix NL PM announced address accounting
commit 4b317e0eb287bd30a1b329513531157c25e8b692 upstream.

Currently the per connection announced address counter is never
decreased. As a consequence, after connection establishment, if
the NL PM deletes an endpoint and adds a new/different one, no
additional subflow is created for the new endpoint even if the
current limits allow that.

Address the issue properly updating the signaled address counter
every time the NL PM removes such addresses.

Fixes: 01cacb00b3 ("mptcp: add netlink-based PM")
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-08-11 12:47:26 +02:00
Matthieu Baerts (NGI0) 8ed3e34c76 mptcp: distinguish rcv vs sent backup flag in requests
commit efd340bf3d7779a3a8ec954d8ec0fb8a10f24982 upstream.

When sending an MP_JOIN + SYN + ACK, it is possible to mark the subflow
as 'backup' by setting the flag with the same name. Before this patch,
the backup was set if the other peer set it in its MP_JOIN + SYN
request.

It is not correct: the backup flag should be set in the MPJ+SYN+ACK only
if the host asks for it, and not mirroring what was done by the other
peer. It is then required to have a dedicated bit for each direction,
similar to what is done in the subflow context.

Fixes: f296234c98 ("mptcp: Add handling of incoming MP_JOIN requests")
Cc: stable@vger.kernel.org
Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-08-11 12:47:26 +02:00
Paolo Abeni 201b76f624 mptcp: fix user-space PM announced address accounting
commit 167b93258d1e2230ee3e8a97669b4db4cc9e90aa upstream.

Currently the per-connection announced address counter is never
decreased. When the user-space PM is in use, this just affect
the information exposed via diag/sockopt, but it could still foul
the PM to wrong decision.

Add the missing accounting for the user-space PM's sake.

Fixes: 8b1c94da1e ("mptcp: only send RM_ADDR in nl_cmd_remove")
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-08-11 12:47:26 +02:00
Matthieu Baerts (NGI0) add243b7f6 mptcp: sched: check both directions for backup
commit b6a66e521a2032f7fcba2af5a9bcbaeaa19b7ca3 upstream.

The 'mptcp_subflow_context' structure has two items related to the
backup flags:

 - 'backup': the subflow has been marked as backup by the other peer

 - 'request_bkup': the backup flag has been set by the host

Before this patch, the scheduler was only looking at the 'backup' flag.
That can make sense in some cases, but it looks like that's not what we
wanted for the general use, because either the path-manager was setting
both of them when sending an MP_PRIO, or the receiver was duplicating
the 'backup' flag in the subflow request.

Note that the use of these two flags in the path-manager are going to be
fixed in the next commits, but this change here is needed not to modify
the behaviour.

Fixes: f296234c98 ("mptcp: Add handling of incoming MP_JOIN requests")
Cc: stable@vger.kernel.org
Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-08-11 12:47:25 +02:00
Eric Dumazet f9fef23a81 tcp: annotate data-races around tp->window_clamp
[ Upstream commit f410cbea9f3d2675b4c8e52af1d1985b11b387d1 ]

tp->window_clamp can be read locklessly, add READ_ONCE()
and WRITE_ONCE() annotations.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Jason Xing <kerneljasonxing@gmail.com>
Link: https://lore.kernel.org/r/20240404114231.2195171-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Stable-dep-of: 05f76b2d634e ("tcp: Adjust clamping window for applications specifying SO_RCVBUF")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-08-11 12:47:19 +02:00
Paolo Abeni 124a4885b5 mptcp: give rcvlowat some love
[ Upstream commit 5684ab1a0effbfeb706f47d85785f653005b97b1 ]

The MPTCP protocol allow setting sk_rcvlowat, but the value there
is currently ignored.

Additionally, the default subflows sk_rcvlowat basically disables per
subflow delayed ack: the MPTCP protocol move the incoming data from the
subflows into the msk socket as soon as the TCP stacks invokes the subflow
data_ready callback. Later, when __tcp_ack_snd_check() takes action,
the subflow-level copied_seq matches rcv_nxt, and that mandate for an
immediate ack.

Let the mptcp receive path be aware of such threshold, explicitly tracking
the amount of data available to be ready and checking vs sk_rcvlowat in
mptcp_poll() and before waking-up readers.

Additionally implement the set_rcvlowat() callback, to properly handle
the rcvbuf auto-tuning on sk_rcvlowat changes.

Finally to properly handle delayed ack, force the subflow level threshold
to 0 and instead explicitly ask for an immediate ack when the msk level th
is not reached.

Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Mat Martineau <martineau@kernel.org>
Link: https://lore.kernel.org/r/20231023-send-net-next-20231023-2-v1-5-9dc60939d371@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Stable-dep-of: 05f76b2d634e ("tcp: Adjust clamping window for applications specifying SO_RCVBUF")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-08-11 12:47:19 +02:00
YonglongLi dbf0787c2f mptcp: pm: update add_addr counters after connect
commit 40eec1795cc27b076d49236649a29507c7ed8c2d upstream.

The creation of new subflows can fail for different reasons. If no
subflow have been created using the received ADD_ADDR, the related
counters should not be updated, otherwise they will never be decremented
for events related to this ID later on.

For the moment, the number of accepted ADD_ADDR is only decremented upon
the reception of a related RM_ADDR, and only if the remote address ID is
currently being used by at least one subflow. In other words, if no
subflow can be created with the received address, the counter will not
be decremented. In this case, it is then important not to increment
pm.add_addr_accepted counter, and not to modify pm.accept_addr bit.

Note that this patch does not modify the behaviour in case of failures
later on, e.g. if the MP Join is dropped or rejected.

The "remove invalid addresses" MP Join subtest has been modified to
validate this case. The broadcast IP address is added before the "valid"
address that will be used to successfully create a subflow, and the
limit is decreased by one: without this patch, it was not possible to
create the last subflow, because:

- the broadcast address would have been accepted even if it was not
  usable: the creation of a subflow to this address results in an error,

- the limit of 2 accepted ADD_ADDR would have then been reached.

Fixes: 01cacb00b3 ("mptcp: add netlink-based PM")
Cc: stable@vger.kernel.org
Co-developed-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Signed-off-by: YonglongLi <liyonglong@chinatelecom.cn>
Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Link: https://lore.kernel.org/r/20240607-upstream-net-20240607-misc-fixes-v1-3-1ab9ddfa3d00@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-06-21 14:38:38 +02:00
YonglongLi 09469a0817 mptcp: pm: inc RmAddr MIB counter once per RM_ADDR ID
commit 6a09788c1a66e3d8b04b3b3e7618cc817bb60ae9 upstream.

The RmAddr MIB counter is supposed to be incremented once when a valid
RM_ADDR has been received. Before this patch, it could have been
incremented as many times as the number of subflows connected to the
linked address ID, so it could have been 0, 1 or more than 1.

The "RmSubflow" is incremented after a local operation. In this case,
it is normal to tied it with the number of subflows that have been
actually removed.

The "remove invalid addresses" MP Join subtest has been modified to
validate this case. A broadcast IP address is now used instead: the
client will not be able to create a subflow to this address. The
consequence is that when receiving the RM_ADDR with the ID attached to
this broadcast IP address, no subflow linked to this ID will be found.

Fixes: 7a7e52e38a ("mptcp: add RM_ADDR related mibs")
Cc: stable@vger.kernel.org
Co-developed-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Signed-off-by: YonglongLi <liyonglong@chinatelecom.cn>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Link: https://lore.kernel.org/r/20240607-upstream-net-20240607-misc-fixes-v1-2-1ab9ddfa3d00@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-06-21 14:38:38 +02:00
Paolo Abeni f1f0a46f8b mptcp: ensure snd_una is properly initialized on connect
commit 8031b58c3a9b1db3ef68b3bd749fbee2e1e1aaa3 upstream.

This is strictly related to commit fb7a0d334894 ("mptcp: ensure snd_nxt
is properly initialized on connect"). It turns out that syzkaller can
trigger the retransmit after fallback and before processing any other
incoming packet - so that snd_una is still left uninitialized.

Address the issue explicitly initializing snd_una together with snd_nxt
and write_seq.

Suggested-by: Mat Martineau <martineau@kernel.org>
Fixes: 8fd738049a ("mptcp: fallback in case of simultaneous connect")
Cc: stable@vger.kernel.org
Reported-by: Christoph Paasch <cpaasch@apple.com>
Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/485
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Link: https://lore.kernel.org/r/20240607-upstream-net-20240607-misc-fixes-v1-1-1ab9ddfa3d00@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-06-21 14:38:38 +02:00
Jason Xing 3dd41669b3 mptcp: count CLOSE-WAIT sockets for MPTCP_MIB_CURRESTAB
[ Upstream commit 9633e9377e6af0244f7381e86b9aac5276f5be97 ]

Like previous patch does in TCP, we need to adhere to RFC 1213:

  "tcpCurrEstab OBJECT-TYPE
   ...
   The number of TCP connections for which the current state
   is either ESTABLISHED or CLOSE- WAIT."

So let's consider CLOSE-WAIT sockets.

The logic of counting
When we increment the counter?
a) Only if we change the state to ESTABLISHED.

When we decrement the counter?
a) if the socket leaves ESTABLISHED and will never go into CLOSE-WAIT,
say, on the client side, changing from ESTABLISHED to FIN-WAIT-1.
b) if the socket leaves CLOSE-WAIT, say, on the server side, changing
from CLOSE-WAIT to LAST-ACK.

Fixes: d9cd27b8cd19 ("mptcp: add CurrEstab MIB counter support")
Signed-off-by: Jason Xing <kernelxing@tencent.com>
Reviewed-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-06-21 14:38:17 +02:00
Matthieu Baerts (NGI0) 184873af87 mptcp: fix full TCP keep-alive support
commit bd11dc4fb969ec148e50cd87f88a78246dbc4d0b upstream.

SO_KEEPALIVE support has been added a while ago, as part of a series
"adding SOL_SOCKET" support. To have a full control of this keep-alive
feature, it is important to also support TCP_KEEP* socket options at the
SOL_TCP level.

Supporting them on the setsockopt() part is easy, it is just a matter of
remembering each value in the MPTCP sock structure, and calling
tcp_sock_set_keep*() helpers on each subflow. If the value is not
modified (0), calling these helpers will not do anything. For the
getsockopt() part, the corresponding value from the MPTCP sock structure
or the default one is simply returned. All of this is very similar to
other TCP_* socket options supported by MPTCP.

It looks important for kernels supporting SO_KEEPALIVE, to also support
TCP_KEEP* options as well: some apps seem to (wrongly) consider that if
the former is supported, the latter ones will be supported as well. But
also, not having this simple and isolated change is preventing MPTCP
support in some apps, and libraries like GoLang [1]. This is why this
patch is seen as a fix.

Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/383
Fixes: 1b3e7ede13 ("mptcp: setsockopt: handle SO_KEEPALIVE and SO_PRIORITY")
Link: https://github.com/golang/go/issues/56539 [1]
Acked-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Signed-off-by: Mat Martineau <martineau@kernel.org>
Link: https://lore.kernel.org/r/20240514011335.176158-3-martineau@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
[ conflicts in the same context, because commit 29b5e5ef8739 ("mptcp:
  implement TCP_NOTSENT_LOWAT support") is not in this version ]
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-06-16 13:47:31 +02:00
Paolo Abeni 89e11fe49f mptcp: cleanup SOL_TCP handling
commit 7f71a337b5152ea0e7bef408d1af53778a919316 upstream.

Most TCP-level socket options get an integer from user space, and
set the corresponding field under the msk-level socket lock.

Reduce the code duplication moving such operations in the common code.

Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Stable-dep-of: bd11dc4fb969 ("mptcp: fix full TCP keep-alive support")
[ Without TCP_NOTSENT_LOWAT support, as it is not in this version, see
  commit 29b5e5ef8739 ("mptcp: implement TCP_NOTSENT_LOWAT support") ]
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-06-16 13:47:31 +02:00
Paolo Abeni 41089d9c8a mptcp: avoid some duplicate code in socket option handling
commit a74762675f700a5473ebe54a671a0788a5b23cc9 upstream.

The mptcp_get_int_option() helper is needless open-coded in a
couple of places, replace the duplicate code with the helper
call.

Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Stable-dep-of: bd11dc4fb969 ("mptcp: fix full TCP keep-alive support")
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-06-16 13:47:30 +02:00
Matthieu Baerts (NGI0) 5f9d2dcf71 mptcp: SO_KEEPALIVE: fix getsockopt support
[ Upstream commit a65198136eaa15b74ee0abf73f12ef83d469a334 ]

SO_KEEPALIVE support has to be set on each subflow: on each TCP socket,
where sk_prot->keepalive is defined. Technically, nothing has to be done
on the MPTCP socket. That's why mptcp_sol_socket_sync_intval() was
called instead of mptcp_sol_socket_intval().

Except that when nothing is done on the MPTCP socket, the
getsockopt(SO_KEEPALIVE), handled in net/core/sock.c:sk_getsockopt(),
will not know if SO_KEEPALIVE has been set on the different subflows or
not.

The fix is simple: simply call mptcp_sol_socket_intval() which will end
up calling net/core/sock.c:sk_setsockopt() where the SOCK_KEEPOPEN flag
will be set, the one used in sk_getsockopt().

So now, getsockopt(SO_KEEPALIVE) on an MPTCP socket will return the same
value as the one previously set with setsockopt(SO_KEEPALIVE).

Fixes: 1b3e7ede13 ("mptcp: setsockopt: handle SO_KEEPALIVE and SO_PRIORITY")
Acked-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Signed-off-by: Mat Martineau <martineau@kernel.org>
Link: https://lore.kernel.org/r/20240514011335.176158-2-martineau@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-06-12 11:11:54 +02:00
Gregory Detal daad878a50 mptcp: only allow set existing scheduler for net.mptcp.scheduler
commit 6963c508fd7ab66ae0b7ae3db9a62ca6267f1ae8 upstream.

The current behavior is to accept any strings as inputs, this results in
an inconsistent result where an unexisting scheduler can be set:

  # sysctl -w net.mptcp.scheduler=notdefault
  net.mptcp.scheduler = notdefault

This patch changes this behavior by checking for existing scheduler
before accepting the input.

Fixes: e3b2870b6d ("mptcp: add a new sysctl scheduler")
Cc: stable@vger.kernel.org
Signed-off-by: Gregory Detal <gregory.detal@gmail.com>
Reviewed-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Tested-by: Geliang Tang <geliang@kernel.org>
Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Link: https://lore.kernel.org/r/20240506-upstream-net-20240506-mptcp-sched-exist-v1-1-2ed1529e521e@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-05-17 12:02:30 +02:00
Paolo Abeni aa0c07c1f2 mptcp: ensure snd_nxt is properly initialized on connect
commit fb7a0d334894206ae35f023a82cad5a290fd7386 upstream.

Christoph reported a splat hinting at a corrupted snd_una:

  WARNING: CPU: 1 PID: 38 at net/mptcp/protocol.c:1005 __mptcp_clean_una+0x4b3/0x620 net/mptcp/protocol.c:1005
  Modules linked in:
  CPU: 1 PID: 38 Comm: kworker/1:1 Not tainted 6.9.0-rc1-gbbeac67456c9 #59
  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.11.0-2.el7 04/01/2014
  Workqueue: events mptcp_worker
  RIP: 0010:__mptcp_clean_una+0x4b3/0x620 net/mptcp/protocol.c:1005
  Code: be 06 01 00 00 bf 06 01 00 00 e8 a8 12 e7 fe e9 00 fe ff ff e8
  	8e 1a e7 fe 0f b7 ab 3e 02 00 00 e9 d3 fd ff ff e8 7d 1a e7 fe
  	<0f> 0b 4c 8b bb e0 05 00 00 e9 74 fc ff ff e8 6a 1a e7 fe 0f 0b e9
  RSP: 0018:ffffc9000013fd48 EFLAGS: 00010293
  RAX: 0000000000000000 RBX: ffff8881029bd280 RCX: ffffffff82382fe4
  RDX: ffff8881003cbd00 RSI: ffffffff823833c3 RDI: 0000000000000001
  RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000000
  R10: 0000000000000000 R11: fefefefefefefeff R12: ffff888138ba8000
  R13: 0000000000000106 R14: ffff8881029bd908 R15: ffff888126560000
  FS:  0000000000000000(0000) GS:ffff88813bd00000(0000) knlGS:0000000000000000
  CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  CR2: 00007f604a5dae38 CR3: 0000000101dac002 CR4: 0000000000170ef0
  Call Trace:
   <TASK>
   __mptcp_clean_una_wakeup net/mptcp/protocol.c:1055 [inline]
   mptcp_clean_una_wakeup net/mptcp/protocol.c:1062 [inline]
   __mptcp_retrans+0x7f/0x7e0 net/mptcp/protocol.c:2615
   mptcp_worker+0x434/0x740 net/mptcp/protocol.c:2767
   process_one_work+0x1e0/0x560 kernel/workqueue.c:3254
   process_scheduled_works kernel/workqueue.c:3335 [inline]
   worker_thread+0x3c7/0x640 kernel/workqueue.c:3416
   kthread+0x121/0x170 kernel/kthread.c:388
   ret_from_fork+0x44/0x50 arch/x86/kernel/process.c:147
   ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:243
   </TASK>

When fallback to TCP happens early on a client socket, snd_nxt
is not yet initialized and any incoming ack will copy such value
into snd_una. If the mptcp worker (dumbly) tries mptcp-level
re-injection after such ack, that would unconditionally trigger a send
buffer cleanup using 'bad' snd_una values.

We could easily disable re-injection for fallback sockets, but such
dumb behavior already helped catching a few subtle issues and a very
low to zero impact in practice.

Instead address the issue always initializing snd_nxt (and write_seq,
for consistency) at connect time.

Fixes: 8fd738049a ("mptcp: fallback in case of simultaneous connect")
Cc: stable@vger.kernel.org
Reported-by: Christoph Paasch <cpaasch@apple.com>
Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/485
Tested-by: Christoph Paasch <cpaasch@apple.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Link: https://lore.kernel.org/r/20240429-upstream-net-20240429-mptcp-snd_nxt-init-connect-v1-1-59ceac0a7dcb@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-05-17 12:02:30 +02:00
Davide Caratti 43eca11b7c mptcp: don't account accept() of non-MPC client as fallback to TCP
commit 7a1b3490f47e88ec4cbde65f1a77a0f4bc972282 upstream.

Current MPTCP servers increment MPTcpExtMPCapableFallbackACK when they
accept non-MPC connections. As reported by Christoph, this is "surprising"
because the counter might become greater than MPTcpExtMPCapableSYNRX.

MPTcpExtMPCapableFallbackACK counter's name suggests it should only be
incremented when a connection was seen using MPTCP options, then a
fallback to TCP has been done. Let's do that by incrementing it when
the subflow context of an inbound MPC connection attempt is dropped.
Also, update mptcp_connect.sh kselftest, to ensure that the
above MIB does not increment in case a pure TCP client connects to a
MPTCP server.

Fixes: fc518953bc ("mptcp: add and use MIB counter infrastructure")
Cc: stable@vger.kernel.org
Reported-by: Christoph Paasch <cpaasch@apple.com>
Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/449
Signed-off-by: Davide Caratti <dcaratti@redhat.com>
Reviewed-by: Mat Martineau <martineau@kernel.org>
Reviewed-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Link: https://lore.kernel.org/r/20240329-upstream-net-20240329-fallback-mib-v1-1-324a8981da48@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-04-10 16:36:06 +02:00
Davide Caratti 12f353fac6 mptcp: don't overwrite sock_ops in mptcp_is_tcpsk()
commit 8e2b8a9fa512709e6fee744dcd4e2a20ee7f5c56 upstream.

Eric Dumazet suggests:

 > The fact that mptcp_is_tcpsk() was able to write over sock->ops was a
 > bit strange to me.
 > mptcp_is_tcpsk() should answer a question, with a read-only argument.

re-factor code to avoid overwriting sock_ops inside that function. Also,
change the helper name to reflect the semantics and to disambiguate from
its dual, sk_is_mptcp(). While at it, collapse mptcp_stream_accept() and
mptcp_accept() into a single function, where fallback / non-fallback are
separated into a single sk_is_mptcp() conditional.

Link: https://github.com/multipath-tcp/mptcp_net-next/issues/432
Suggested-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Davide Caratti <dcaratti@redhat.com>
Acked-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Matthieu Baerts <matttbe@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-04-10 16:36:06 +02:00
Paolo Abeni fa8c776f4c mptcp: fix possible deadlock in subflow diag
commit d6a9608af9a75d13243d217f6ce1e30e57d56ffe upstream.

Syzbot and Eric reported a lockdep splat in the subflow diag:

   WARNING: possible circular locking dependency detected
   6.8.0-rc4-syzkaller-00212-g40b9385dd8e6 #0 Not tainted

   syz-executor.2/24141 is trying to acquire lock:
   ffff888045870130 (k-sk_lock-AF_INET6){+.+.}-{0:0}, at:
   tcp_diag_put_ulp net/ipv4/tcp_diag.c:100 [inline]
   ffff888045870130 (k-sk_lock-AF_INET6){+.+.}-{0:0}, at:
   tcp_diag_get_aux+0x738/0x830 net/ipv4/tcp_diag.c:137

   but task is already holding lock:
   ffffc9000135e488 (&h->lhash2[i].lock){+.+.}-{2:2}, at: spin_lock
   include/linux/spinlock.h:351 [inline]
   ffffc9000135e488 (&h->lhash2[i].lock){+.+.}-{2:2}, at:
   inet_diag_dump_icsk+0x39f/0x1f80 net/ipv4/inet_diag.c:1038

   which lock already depends on the new lock.

   the existing dependency chain (in reverse order) is:

   -> #1 (&h->lhash2[i].lock){+.+.}-{2:2}:
   lock_acquire+0x1e3/0x530 kernel/locking/lockdep.c:5754
   __raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline]
   _raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:154
   spin_lock include/linux/spinlock.h:351 [inline]
   __inet_hash+0x335/0xbe0 net/ipv4/inet_hashtables.c:743
   inet_csk_listen_start+0x23a/0x320 net/ipv4/inet_connection_sock.c:1261
   __inet_listen_sk+0x2a2/0x770 net/ipv4/af_inet.c:217
   inet_listen+0xa3/0x110 net/ipv4/af_inet.c:239
   rds_tcp_listen_init+0x3fd/0x5a0 net/rds/tcp_listen.c:316
   rds_tcp_init_net+0x141/0x320 net/rds/tcp.c:577
   ops_init+0x352/0x610 net/core/net_namespace.c:136
   __register_pernet_operations net/core/net_namespace.c:1214 [inline]
   register_pernet_operations+0x2cb/0x660 net/core/net_namespace.c:1283
   register_pernet_device+0x33/0x80 net/core/net_namespace.c:1370
   rds_tcp_init+0x62/0xd0 net/rds/tcp.c:735
   do_one_initcall+0x238/0x830 init/main.c:1236
   do_initcall_level+0x157/0x210 init/main.c:1298
   do_initcalls+0x3f/0x80 init/main.c:1314
   kernel_init_freeable+0x42f/0x5d0 init/main.c:1551
   kernel_init+0x1d/0x2a0 init/main.c:1441
   ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
   ret_from_fork_asm+0x1b/0x30 arch/x86/entry/entry_64.S:242

   -> #0 (k-sk_lock-AF_INET6){+.+.}-{0:0}:
   check_prev_add kernel/locking/lockdep.c:3134 [inline]
   check_prevs_add kernel/locking/lockdep.c:3253 [inline]
   validate_chain+0x18ca/0x58e0 kernel/locking/lockdep.c:3869
   __lock_acquire+0x1345/0x1fd0 kernel/locking/lockdep.c:5137
   lock_acquire+0x1e3/0x530 kernel/locking/lockdep.c:5754
   lock_sock_fast include/net/sock.h:1723 [inline]
   subflow_get_info+0x166/0xd20 net/mptcp/diag.c:28
   tcp_diag_put_ulp net/ipv4/tcp_diag.c:100 [inline]
   tcp_diag_get_aux+0x738/0x830 net/ipv4/tcp_diag.c:137
   inet_sk_diag_fill+0x10ed/0x1e00 net/ipv4/inet_diag.c:345
   inet_diag_dump_icsk+0x55b/0x1f80 net/ipv4/inet_diag.c:1061
   __inet_diag_dump+0x211/0x3a0 net/ipv4/inet_diag.c:1263
   inet_diag_dump_compat+0x1c1/0x2d0 net/ipv4/inet_diag.c:1371
   netlink_dump+0x59b/0xc80 net/netlink/af_netlink.c:2264
   __netlink_dump_start+0x5df/0x790 net/netlink/af_netlink.c:2370
   netlink_dump_start include/linux/netlink.h:338 [inline]
   inet_diag_rcv_msg_compat+0x209/0x4c0 net/ipv4/inet_diag.c:1405
   sock_diag_rcv_msg+0xe7/0x410
   netlink_rcv_skb+0x1e3/0x430 net/netlink/af_netlink.c:2543
   sock_diag_rcv+0x2a/0x40 net/core/sock_diag.c:280
   netlink_unicast_kernel net/netlink/af_netlink.c:1341 [inline]
   netlink_unicast+0x7ea/0x980 net/netlink/af_netlink.c:1367
   netlink_sendmsg+0xa3b/0xd70 net/netlink/af_netlink.c:1908
   sock_sendmsg_nosec net/socket.c:730 [inline]
   __sock_sendmsg+0x221/0x270 net/socket.c:745
   ____sys_sendmsg+0x525/0x7d0 net/socket.c:2584
   ___sys_sendmsg net/socket.c:2638 [inline]
   __sys_sendmsg+0x2b0/0x3a0 net/socket.c:2667
   do_syscall_64+0xf9/0x240
   entry_SYSCALL_64_after_hwframe+0x6f/0x77

As noted by Eric we can break the lock dependency chain avoid
dumping any extended info for the mptcp subflow listener:
nothing actually useful is presented there.

Fixes: b8adb69a7d29 ("mptcp: fix lockless access in subflow ULP diag")
Cc: stable@vger.kernel.org
Reported-by: Eric Dumazet <edumazet@google.com>
Closes: https://lore.kernel.org/netdev/CANn89iJ=Oecw6OZDwmSYc9HJKQ_G32uN11L+oUcMu+TOD5Xiaw@mail.gmail.com/
Suggested-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Link: https://lore.kernel.org/r/20240223-upstream-net-20240223-misc-fixes-v1-9-162e87e48497@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-03-06 14:48:42 +00:00
Davide Caratti ce0809ada3 mptcp: fix double-free on socket dismantle
commit 10048689def7e40a4405acda16fdc6477d4ecc5c upstream.

when MPTCP server accepts an incoming connection, it clones its listener
socket. However, the pointer to 'inet_opt' for the new socket has the same
value as the original one: as a consequence, on program exit it's possible
to observe the following splat:

  BUG: KASAN: double-free in inet_sock_destruct+0x54f/0x8b0
  Free of addr ffff888485950880 by task swapper/25/0

  CPU: 25 PID: 0 Comm: swapper/25 Kdump: loaded Not tainted 6.8.0-rc1+ #609
  Hardware name: Supermicro SYS-6027R-72RF/X9DRH-7TF/7F/iTF/iF, BIOS 3.0  07/26/2013
  Call Trace:
   <IRQ>
   dump_stack_lvl+0x32/0x50
   print_report+0xca/0x620
   kasan_report_invalid_free+0x64/0x90
   __kasan_slab_free+0x1aa/0x1f0
   kfree+0xed/0x2e0
   inet_sock_destruct+0x54f/0x8b0
   __sk_destruct+0x48/0x5b0
   rcu_do_batch+0x34e/0xd90
   rcu_core+0x559/0xac0
   __do_softirq+0x183/0x5a4
   irq_exit_rcu+0x12d/0x170
   sysvec_apic_timer_interrupt+0x6b/0x80
   </IRQ>
   <TASK>
   asm_sysvec_apic_timer_interrupt+0x16/0x20
  RIP: 0010:cpuidle_enter_state+0x175/0x300
  Code: 30 00 0f 84 1f 01 00 00 83 e8 01 83 f8 ff 75 e5 48 83 c4 18 44 89 e8 5b 5d 41 5c 41 5d 41 5e 41 5f c3 cc cc cc cc fb 45 85 ed <0f> 89 60 ff ff ff 48 c1 e5 06 48 c7 43 18 00 00 00 00 48 83 44 2b
  RSP: 0018:ffff888481cf7d90 EFLAGS: 00000202
  RAX: 0000000000000000 RBX: ffff88887facddc8 RCX: 0000000000000000
  RDX: 1ffff1110ff588b1 RSI: 0000000000000019 RDI: ffff88887fac4588
  RBP: 0000000000000004 R08: 0000000000000002 R09: 0000000000043080
  R10: 0009b02ea273363f R11: ffff88887fabf42b R12: ffffffff932592e0
  R13: 0000000000000004 R14: 0000000000000000 R15: 00000022c880ec80
   cpuidle_enter+0x4a/0xa0
   do_idle+0x310/0x410
   cpu_startup_entry+0x51/0x60
   start_secondary+0x211/0x270
   secondary_startup_64_no_verify+0x184/0x18b
   </TASK>

  Allocated by task 6853:
   kasan_save_stack+0x1c/0x40
   kasan_save_track+0x10/0x30
   __kasan_kmalloc+0xa6/0xb0
   __kmalloc+0x1eb/0x450
   cipso_v4_sock_setattr+0x96/0x360
   netlbl_sock_setattr+0x132/0x1f0
   selinux_netlbl_socket_post_create+0x6c/0x110
   selinux_socket_post_create+0x37b/0x7f0
   security_socket_post_create+0x63/0xb0
   __sock_create+0x305/0x450
   __sys_socket_create.part.23+0xbd/0x130
   __sys_socket+0x37/0xb0
   __x64_sys_socket+0x6f/0xb0
   do_syscall_64+0x83/0x160
   entry_SYSCALL_64_after_hwframe+0x6e/0x76

  Freed by task 6858:
   kasan_save_stack+0x1c/0x40
   kasan_save_track+0x10/0x30
   kasan_save_free_info+0x3b/0x60
   __kasan_slab_free+0x12c/0x1f0
   kfree+0xed/0x2e0
   inet_sock_destruct+0x54f/0x8b0
   __sk_destruct+0x48/0x5b0
   subflow_ulp_release+0x1f0/0x250
   tcp_cleanup_ulp+0x6e/0x110
   tcp_v4_destroy_sock+0x5a/0x3a0
   inet_csk_destroy_sock+0x135/0x390
   tcp_fin+0x416/0x5c0
   tcp_data_queue+0x1bc8/0x4310
   tcp_rcv_state_process+0x15a3/0x47b0
   tcp_v4_do_rcv+0x2c1/0x990
   tcp_v4_rcv+0x41fb/0x5ed0
   ip_protocol_deliver_rcu+0x6d/0x9f0
   ip_local_deliver_finish+0x278/0x360
   ip_local_deliver+0x182/0x2c0
   ip_rcv+0xb5/0x1c0
   __netif_receive_skb_one_core+0x16e/0x1b0
   process_backlog+0x1e3/0x650
   __napi_poll+0xa6/0x500
   net_rx_action+0x740/0xbb0
   __do_softirq+0x183/0x5a4

  The buggy address belongs to the object at ffff888485950880
   which belongs to the cache kmalloc-64 of size 64
  The buggy address is located 0 bytes inside of
   64-byte region [ffff888485950880, ffff8884859508c0)

  The buggy address belongs to the physical page:
  page:0000000056d1e95e refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff888485950700 pfn:0x485950
  flags: 0x57ffffc0000800(slab|node=1|zone=2|lastcpupid=0x1fffff)
  page_type: 0xffffffff()
  raw: 0057ffffc0000800 ffff88810004c640 ffffea00121b8ac0 dead000000000006
  raw: ffff888485950700 0000000000200019 00000001ffffffff 0000000000000000
  page dumped because: kasan: bad access detected

  Memory state around the buggy address:
   ffff888485950780: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
   ffff888485950800: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
  >ffff888485950880: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
                     ^
   ffff888485950900: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
   ffff888485950980: 00 00 00 00 00 01 fc fc fc fc fc fc fc fc fc fc

Something similar (a refcount underflow) happens with CALIPSO/IPv6. Fix
this by duplicating IP / IPv6 options after clone, so that
ip{,6}_sock_destruct() doesn't end up freeing the same memory area twice.

Fixes: cf7da0d66c ("mptcp: Create SUBFLOW socket for incoming connections")
Cc: stable@vger.kernel.org
Signed-off-by: Davide Caratti <dcaratti@redhat.com>
Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Link: https://lore.kernel.org/r/20240223-upstream-net-20240223-misc-fixes-v1-8-162e87e48497@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-03-06 14:48:42 +00:00
Paolo Abeni b609ecda2d mptcp: fix potential wake-up event loss
commit b111d8fbd2cbc63e05f3adfbbe0d4df655dfcc5b upstream.

After the blamed commit below, the send buffer auto-tuning can
happen after that the mptcp_propagate_sndbuf() completes - via
the delegated action infrastructure.

We must check for write space even after such change or we risk
missing the wake-up event.

Fixes: 8005184fd1ca ("mptcp: refactor sndbuf auto-tuning")
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Link: https://lore.kernel.org/r/20240223-upstream-net-20240223-misc-fixes-v1-6-162e87e48497@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-03-06 14:48:42 +00:00
Paolo Abeni ae5530ccd5 mptcp: fix snd_wnd initialization for passive socket
commit adf1bb78dab55e36d4d557aa2fb446ebcfe9e5ce upstream.

Such value should be inherited from the first subflow, but
passive sockets always used 'rsk_rcv_wnd'.

Fixes: 6f8a612a33 ("mptcp: keep track of advertised windows right edge")
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Link: https://lore.kernel.org/r/20240223-upstream-net-20240223-misc-fixes-v1-5-162e87e48497@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-03-06 14:48:42 +00:00
Paolo Abeni 48428b07de mptcp: push at DSS boundaries
commit b9cd26f640a308ea314ad23532de9a8592cd09d2 upstream.

when inserting not contiguous data in the subflow write queue,
the protocol creates a new skb and prevent the TCP stack from
merging it later with already queued skbs by setting the EOR marker.

Still no push flag is explicitly set at the end of previous GSO
packet, making the aggregation on the receiver side sub-optimal -
and packetdrill self-tests less predictable.

Explicitly mark the end of not contiguous DSS with the push flag.

Fixes: 6d0060f600 ("mptcp: Write MPTCP DSS headers to outgoing data packets")
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Link: https://lore.kernel.org/r/20240223-upstream-net-20240223-misc-fixes-v1-4-162e87e48497@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-03-06 14:48:42 +00:00
Matthieu Baerts (NGI0) fca4e6ab06 mptcp: avoid printing warning once on client side
commit 5b49c41ac8f27aa3a63a1712b1f54f91015c18f2 upstream.

After the 'Fixes' commit mentioned below, the client side might print
the following warning once when a subflow is fully established at the
reception of any valid additional ack:

  MPTCP: bogus mpc option on established client sk

That's a normal situation, and no warning should be printed for that. We
can then skip the check when the label is used.

Fixes: e4a0fa47e816 ("mptcp: corner case locking for rx path fields initialization")
Cc: stable@vger.kernel.org
Suggested-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Link: https://lore.kernel.org/r/20240223-upstream-net-20240223-misc-fixes-v1-3-162e87e48497@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-03-06 14:48:42 +00:00
Geliang Tang a49ecbe8d0 mptcp: map v4 address to v6 when destroying subflow
commit 535d620ea5ff1a033dc64ee3d912acadc7470619 upstream.

Address family of server side mismatches with that of client side, like
in "userspace pm add & remove address" test:

    userspace_pm_add_addr $ns1 10.0.2.1 10
    userspace_pm_rm_sf $ns1 "::ffff:10.0.2.1" $SUB_ESTABLISHED

That's because on the server side, the family is set to AF_INET6 and the
v4 address is mapped in a v6 one.

This patch fixes this issue. In mptcp_pm_nl_subflow_destroy_doit(), before
checking local address family with remote address family, map an IPv4
address to an IPv6 address if the pair is a v4-mapped address.

Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/387
Fixes: 702c2f646d ("mptcp: netlink: allow userspace-driven subflow establishment")
Cc: stable@vger.kernel.org
Signed-off-by: Geliang Tang <tanggeliang@kylinos.cn>
Reviewed-by: Mat Martineau <martineau@kernel.org>
Reviewed-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Link: https://lore.kernel.org/r/20240223-upstream-net-20240223-misc-fixes-v1-1-162e87e48497@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-03-06 14:48:42 +00:00
Geliang Tang 7e7a81f9f2 mptcp: add needs_id for netlink appending addr
commit 584f3894262634596532cf43a5e782e34a0ce374 upstream.

Just the same as userspace PM, a new parameter needs_id is added for
in-kernel PM mptcp_pm_nl_append_new_local_addr() too.

Add a new helper mptcp_pm_has_addr_attr_id() to check whether an address
ID is set from PM or not.

In mptcp_pm_nl_get_local_id(), needs_id is always true, but in
mptcp_pm_nl_add_addr_doit(), pass mptcp_pm_has_addr_attr_id() to
needs_it.

Fixes: efd5a4c04e ("mptcp: add the address ID assignment bitmap")
Cc: stable@vger.kernel.org
Signed-off-by: Geliang Tang <tanggeliang@kylinos.cn>
Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-03-01 13:35:11 +01:00
Geliang Tang 6931f9029a mptcp: userspace pm send RM_ADDR for ID 0
commit 84c531f54ad9a124a924c9505d74e33d16965146 upstream.

This patch adds the ability to send RM_ADDR for local ID 0. Check
whether id 0 address is removed, if not, put id 0 into a removing
list, pass it to mptcp_pm_remove_addr() to remove id 0 address.

There is no reason not to allow the userspace to remove the initial
address (ID 0). This special case was not taken into account not
letting the userspace to delete all addresses as announced.

Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/379
Reviewed-by: Matthieu Baerts <matttbe@kernel.org>
Signed-off-by: Geliang Tang <geliang.tang@suse.com>
Signed-off-by: Mat Martineau <martineau@kernel.org>
Link: https://lore.kernel.org/r/20231025-send-net-next-20231025-v1-3-db8f25f798eb@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Fixes: d9a4594eda ("mptcp: netlink: Add MPTCP_PM_CMD_REMOVE")
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-03-01 13:35:11 +01:00
Paolo Abeni 1ea7b252b4 mptcp: fix duplicate subflow creation
commit 045e9d812868a2d80b7a57b224ce8009444b7bbc upstream.

Fullmesh endpoints could end-up unexpectedly generating duplicate
subflows - same local and remote addresses - when multiple incoming
ADD_ADDR are processed before the PM creates the subflow for the local
endpoints.

Address the issue explicitly checking for duplicates at subflow
creation time.

To avoid a quadratic computational complexity, track the unavailable
remote address ids in a temporary bitmap and initialize such bitmap
with the remote ids of all the existing subflows matching the local
address currently processed.

The above allows additionally replacing the existing code checking
for duplicate entry in the current set with a simple bit test
operation.

Fixes: 2843ff6f36 ("mptcp: remote addresses fullmesh")
Cc: stable@vger.kernel.org
Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/435
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-03-01 13:35:03 +01:00
Paolo Abeni 2dba5774e8 mptcp: fix data races on remote_id
commit 967d3c27127e71a10ff5c083583a038606431b61 upstream.

Similar to the previous patch, address the data race on
remote_id, adding the suitable ONCE annotations.

Fixes: bedee0b561 ("mptcp: address lookup improvements")
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-03-01 13:35:03 +01:00
Paolo Abeni ba2cf92250 mptcp: fix data races on local_id
commit a7cfe776637004a4c938fde78be4bd608c32c3ef upstream.

The local address id is accessed lockless by the NL PM, add
all the required ONCE annotation. There is a caveat: the local
id can be initialized late in the subflow life-cycle, and its
validity is controlled by the local_id_valid flag.

Remove such flag and encode the validity in the local_id field
itself with negative value before initialization. That allows
accessing the field consistently with a single read operation.

Fixes: 0ee4261a36 ("mptcp: implement mptcp_pm_remove_subflow")
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-03-01 13:35:03 +01:00
Paolo Abeni e074c8297e mptcp: fix lockless access in subflow ULP diag
commit b8adb69a7d29c2d33eb327bca66476fb6066516b upstream.

Since the introduction of the subflow ULP diag interface, the
dump callback accessed all the subflow data with lockless.

We need either to annotate all the read and write operation accordingly,
or acquire the subflow socket lock. Let's do latter, even if slower, to
avoid a diffstat havoc.

Fixes: 5147dfb508 ("mptcp: allow dumping subflow context to userspace")
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-03-01 13:35:02 +01:00
Geliang Tang 176421d7af mptcp: add needs_id for userspace appending addr
commit 6c347be62ae963b301ead8e7fa7b9973e6e0d6e1 upstream.

When userspace PM requires to create an ID 0 subflow in "userspace pm
create id 0 subflow" test like this:

        userspace_pm_add_sf $ns2 10.0.3.2 0

An ID 1 subflow, in fact, is created.

Since in mptcp_pm_nl_append_new_local_addr(), 'id 0' will be treated as
no ID is set by userspace, and will allocate a new ID immediately:

     if (!e->addr.id)
             e->addr.id = find_next_zero_bit(pernet->id_bitmap,
                                             MPTCP_PM_MAX_ADDR_ID + 1,
                                             1);

To solve this issue, a new parameter needs_id is added for
mptcp_userspace_pm_append_new_local_addr() to distinguish between
whether userspace PM has set an ID 0 or whether userspace PM has
not set any address.

needs_id is true in mptcp_userspace_pm_get_local_id(), but false in
mptcp_pm_nl_announce_doit() and mptcp_pm_nl_subflow_create_doit().

Fixes: e5ed101a60 ("mptcp: userspace pm allow creating id 0 subflow")
Cc: stable@vger.kernel.org
Signed-off-by: Geliang Tang <tanggeliang@kylinos.cn>
Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-03-01 13:35:02 +01:00
Paolo Abeni b45df837fe mptcp: corner case locking for rx path fields initialization
[ Upstream commit e4a0fa47e816e186f6b4c0055d07eeec42d11871 ]

Most MPTCP-level related fields are under the mptcp data lock
protection, but are written one-off without such lock at MPC
complete time, both for the client and the server

Leverage the mptcp_propagate_state() infrastructure to move such
initialization under the proper lock client-wise.

The server side critical init steps are done by
mptcp_subflow_fully_established(): ensure the caller properly held the
relevant lock, and avoid acquiring the same lock in the nested scopes.

There are no real potential races, as write access to such fields
is implicitly serialized by the MPTCP state machine; the primary
goal is consistency.

Fixes: d22f4988ff ("mptcp: process MP_CAPABLE data option")
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-03-01 13:34:57 +01:00
Paolo Abeni 9326d0357a mptcp: fix more tx path fields initialization
[ Upstream commit 3f83d8a77eeeb47011b990fd766a421ee64f1d73 ]

The 'msk->write_seq' and 'msk->snd_nxt' are always updated under
the msk socket lock, except at MPC handshake completiont time.

Builds-up on the previous commit to move such init under the relevant
lock.

There are no known problems caused by the potential race, the
primary goal is consistency.

Fixes: 6d0060f600 ("mptcp: Write MPTCP DSS headers to outgoing data packets")
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Stable-dep-of: e4a0fa47e816 ("mptcp: corner case locking for rx path fields initialization")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-03-01 13:34:57 +01:00
Geliang Tang d52b3c2b29 mptcp: use mptcp_set_state
[ Upstream commit c693a8516429908da3ea111b0caa3c042ab1e6e9 ]

This patch replaces all the 'inet_sk_state_store()' calls under net/mptcp
with the new helper mptcp_set_state().

Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/460
Signed-off-by: Geliang Tang <geliang.tang@linux.dev>
Acked-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Matthieu Baerts <matttbe@kernel.org>
Signed-off-by: Matthieu Baerts <matttbe@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Stable-dep-of: e4a0fa47e816 ("mptcp: corner case locking for rx path fields initialization")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-03-01 13:34:57 +01:00
Geliang Tang 5655754731 mptcp: add CurrEstab MIB counter support
[ Upstream commit d9cd27b8cd191133e287e5de107f971136abe8a2 ]

Add a new MIB counter named MPTCP_MIB_CURRESTAB to count current
established MPTCP connections, similar to TCP_MIB_CURRESTAB. This is
useful to quickly list the number of MPTCP connections without having to
iterate over all of them.

This patch adds a new helper function mptcp_set_state(): if the state
switches from or to ESTABLISHED state, this newly added counter is
incremented. This helper is going to be used in the following patch.

Similar to MPTCP_INC_STATS(), a new helper called MPTCP_DEC_STATS() is
also needed to decrement a MIB counter.

Signed-off-by: Geliang Tang <geliang.tang@linux.dev>
Acked-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Matthieu Baerts <matttbe@kernel.org>
Signed-off-by: Matthieu Baerts <matttbe@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Stable-dep-of: e4a0fa47e816 ("mptcp: corner case locking for rx path fields initialization")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-03-01 13:34:57 +01:00
Paolo Abeni 4bfe217e07 mptcp: really cope with fastopen race
commit 337cebbd850f94147cee05252778f8f78b8c337f upstream.

Fastopen and PM-trigger subflow shutdown can race, as reported by
syzkaller.

In my first attempt to close such race, I missed the fact that
the subflow status can change again before the subflow_state_change
callback is invoked.

Address the issue additionally copying with all the states directly
reachable from TCP_FIN_WAIT1.

Fixes: 1e777f39b4 ("mptcp: add MSG_FASTOPEN sendmsg flag support")
Fixes: 4fd19a307016 ("mptcp: fix inconsistent state on fastopen race")
Cc: stable@vger.kernel.org
Reported-by: syzbot+c53d4d3ddb327e80bc51@syzkaller.appspotmail.com
Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/458
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-02-23 09:25:01 +01:00
Geliang Tang ed34dfa19d mptcp: check addrs list in userspace_pm_get_local_id
commit f012d796a6de662692159c539689e47e662853a8 upstream.

Before adding a new entry in mptcp_userspace_pm_get_local_id(), it's
better to check whether this address is already in userspace pm local
address list. If it's in the list, no need to add a new entry, just
return it's address ID and use this address.

Fixes: 8b20137012 ("mptcp: read attributes of addr entries managed by userspace PMs")
Cc: stable@vger.kernel.org
Signed-off-by: Geliang Tang <geliang.tang@linux.dev>
Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-02-23 09:25:00 +01:00