linux.git/net/mptcp/protocol.c, branch v6.5

mptcp: avoid bogus reset on fallback close

2023-08-05T01:26:27+00:00

Since the blamed commit, the MPTCP protocol unconditionally sends
TCP resets on all the subflows on disconnect().

That fits full-blown MPTCP sockets - to implement the fastclose
mechanism - but causes unexpected corruption of the data stream,
caught as sporadic self-tests failures.

Fixes: d21f83485518 ("mptcp: use fastclose on more edge scenarios")
Cc: stable@vger.kernel.org
Tested-by: Matthieu Baerts 
Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/419
Signed-off-by: Paolo Abeni 
Reviewed-by: Matthieu Baerts 
Signed-off-by: Matthieu Baerts 
Link: https://lore.kernel.org/r/20230803-upstream-net-20230803-misc-fixes-6-5-v1-3-6671b1ab11cc@tessares.net
Signed-off-by: Jakub Kicinski

mptcp: fix the incorrect judgment for msk->cb_flags

2023-08-04T22:22:13+00:00

Coccicheck reports the error below:
net/mptcp/protocol.c:3330:15-28: ERROR: test of a variable/field address

Since the address of msk->cb_flags is used in __test_and_clear_bit, the
address should not be NULL. The judgment for if (unlikely(msk->cb_flags))
will always be true, we should check the real value of msk->cb_flags here.

Fixes: 65a569b03ca8 ("mptcp: optimize release_cb for the common case")
Signed-off-by: Xiang Yang 
Reviewed-by: Matthieu Baerts 
Link: https://lore.kernel.org/r/20230803072438.1847500-1-xiangyang3@huawei.com
Signed-off-by: Jakub Kicinski

mptcp: more accurate NL event generation

2023-07-26T23:48:54+00:00

Currently the mptcp code generate a "new listener" event even
if the actual listen() syscall fails. Address the issue moving
the event generation call under the successful branch.

Cc: stable@vger.kernel.org
Fixes: f8c9dfbd875b ("mptcp: add pm listener events")
Reviewed-by: Mat Martineau 
Signed-off-by: Paolo Abeni 
Signed-off-by: Mat Martineau 
Link: https://lore.kernel.org/r/20230725-send-net-20230725-v1-2-6f60fe7137a9@kernel.org
Signed-off-by: Jakub Kicinski

mptcp: do not rely on implicit state check in mptcp_listen()

2023-07-05T09:51:14+00:00

Since the blamed commit, closing the first subflow resets the first
subflow socket state to SS_UNCONNECTED.

The current mptcp listen implementation relies only on such
state to prevent touching not-fully-disconnected sockets.

Incoming mptcp fastclose (or paired endpoint removal) unconditionally
closes the first subflow.

All the above allows an incoming fastclose followed by a listen() call
to successfully race with a blocking recvmsg(), potentially causing the
latter to hit a divide by zero bug in cleanup_rbuf/__tcp_select_window().

Address the issue explicitly checking the msk socket state in
mptcp_listen(). An alternative solution would be moving the first
subflow socket state update into mptcp_disconnect(), but in the long
term the first subflow socket should be removed: better avoid relaying
on it for internal consistency check.

Fixes: b29fcfb54cd7 ("mptcp: full disconnect implementation")
Cc: stable@vger.kernel.org
Reported-by: Christoph Paasch 
Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/414
Signed-off-by: Paolo Abeni 
Reviewed-by: Matthieu Baerts 
Signed-off-by: Matthieu Baerts 
Signed-off-by: David S. Miller

mptcp: ensure subflow is unhashed before cleaning the backlog

2023-07-05T09:51:14+00:00

While tacking care of the mptcp-level listener I unintentionally
moved the subflow level unhash after the subflow listener backlog
cleanup.

That could cause some nasty race and makes the code harder to read.

Address the issue restoring the proper order of operations.

Fixes: 57fc0f1ceaa4 ("mptcp: ensure listener is unhashed before updating the sk status")
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Abeni 
Reviewed-by: Matthieu Baerts 
Signed-off-by: Matthieu Baerts 
Signed-off-by: David S. Miller

sock: Remove ->sendpage*() in favour of sendmsg(MSG_SPLICE_PAGES)

2023-06-24T22:50:13+00:00

Remove ->sendpage() and ->sendpage_locked().  sendmsg() with
MSG_SPLICE_PAGES should be used instead.  This allows multiple pages and
multipage folios to be passed through.

Signed-off-by: David Howells 
Acked-by: Marc Kleine-Budde  # for net/can
cc: Jens Axboe 
cc: Matthew Wilcox 
cc: linux-afs@lists.infradead.org
cc: mptcp@lists.linux.dev
cc: rds-devel@oss.oracle.com
cc: tipc-discussion@lists.sourceforge.net
cc: virtualization@lists.linux-foundation.org
Link: https://lore.kernel.org/r/20230623225513.2732256-16-dhowells@redhat.com
Signed-off-by: Jakub Kicinski

Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net

2023-06-23T01:40:38+00:00

Cross-merge networking fixes after downstream PR.

Conflicts:

tools/testing/selftests/net/fcnal-test.sh
  d7a2fc1437f7 ("selftests: net: fcnal-test: check if FIPS mode is enabled")
  dd017c72dde6 ("selftests: fcnal: Test SO_DONTROUTE on TCP sockets.")
https://lore.kernel.org/all/5007b52c-dd16-dbf6-8d64-b9701bfa498b@tessares.net/
https://lore.kernel.org/all/20230619105427.4a0df9b3@canb.auug.org.au/

No adjacent changes.

Signed-off-by: Jakub Kicinski

mptcp: consolidate transition to TCP_CLOSE in mptcp_do_fastclose()

2023-06-22T05:45:58+00:00

The MPTCP code always set the msk state to TCP_CLOSE before
calling performing the fast-close. Move such state transition in
mptcp_do_fastclose() to avoid some code duplication.

Signed-off-by: Paolo Abeni 
Reviewed-by: Matthieu Baerts 
Signed-off-by: Matthieu Baerts 
Signed-off-by: Jakub Kicinski

mptcp: add subflow unique id

2023-06-22T05:45:57+00:00

The user-space need to properly account the data received/sent by
individual subflows. When additional subflows are created and/or
closed during the MPTCP socket lifetime, the information currently
exposed via MPTCP_TCPINFO are not enough: subflows are identified only
by the sequential position inside the info dumps, and that will change
with the above mentioned events.

To solve the above problem, this patch introduces a new subflow
identifier that is unique inside the given MPTCP socket scope.

The initial subflow get the id 1 and the other subflows get incremental
values at join time.

Link: https://github.com/multipath-tcp/mptcp_net-next/issues/388
Signed-off-by: Paolo Abeni 
Reviewed-by: Matthieu Baerts 
Signed-off-by: Matthieu Baerts 
Signed-off-by: Jakub Kicinski

mptcp: track some aggregate data counters

2023-06-22T05:45:57+00:00

Currently there are no data transfer counters accounting for all
the subflows used by a given MPTCP socket. The user-space can compute
such figures aggregating the subflow info, but that is inaccurate
if any subflow is closed before the MPTCP socket itself.

Add the new counters in the MPTCP socket itself and expose them
via the existing diag and sockopt. While touching mptcp_diag_fill_info(),
acquire the relevant locks before fetching the msk data, to ensure
better data consistency

Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/385
Signed-off-by: Paolo Abeni 
Reviewed-by: Matthieu Baerts 
Signed-off-by: Matthieu Baerts 
Signed-off-by: Jakub Kicinski