Commit Graph

1002 Commits

Author SHA1 Message Date
Menglong Dong c558246ee7 mptcp: add statistics for mptcp socket in use
Do the statistics of mptcp socket in use with sock_prot_inuse_add().
Therefore, we can get the count of used mptcp socket from
/proc/net/protocols:

& cat /proc/net/protocols
protocol  size sockets  memory press maxhdr  slab module     cl co di ac io in de sh ss gs se re sp bi br ha uh gp em
MPTCPv6   2048      0       0   no       0   yes  kernel      y  n  y  y  y  y  y  y  y  y  y  y  n  n  n  y  y  y  n
MPTCP     1896      1       0   no       0   yes  kernel      y  n  y  y  y  y  y  y  y  y  y  y  n  n  n  y  y  y  n

Acked-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Menglong Dong <imagedong@tencent.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2023-01-09 07:30:50 +00:00
Menglong Dong 294de90909 mptcp: rename 'sk' to 'ssk' in mptcp_token_new_connect()
'ssk' should be more appropriate to be the name of the first argument
in mptcp_token_new_connect().

Acked-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Menglong Dong <imagedong@tencent.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2023-01-09 07:30:50 +00:00
Menglong Dong ade4d75462 mptcp: init sk->sk_prot in build_msk()
The 'sk_prot' field in token KUNIT self-tests will be dereferenced in
mptcp_token_new_connect(). Therefore, init it with tcp_prot.

Acked-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Menglong Dong <imagedong@tencent.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2023-01-09 07:30:50 +00:00
Menglong Dong cfdcfeed64 mptcp: introduce 'sk' to replace 'sock->sk' in mptcp_listen()
'sock->sk' is used frequently in mptcp_listen(). Therefore, we can
introduce the 'sk' and replace 'sock->sk' with it.

Acked-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Menglong Dong <imagedong@tencent.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2023-01-09 07:30:50 +00:00
Geliang Tang 3c976f4c99 mptcp: use local variable ssk in write_options
The local variable 'ssk' has been defined at the beginning of the function
mptcp_write_options(), use it instead of getting 'ssk' again.

Reviewed-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Geliang Tang <geliang.tang@suse.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2023-01-09 07:30:49 +00:00
Geliang Tang a963853fd4 mptcp: use net instead of sock_net
Use the local variable 'net' instead of sock_net() in the functions where
the variable 'struct net *net' has been defined.

Reviewed-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Geliang Tang <geliang.tang@suse.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2023-01-09 07:30:49 +00:00
Geliang Tang 109cdeb8df mptcp: use msk_owned_by_me helper
The helper msk_owned_by_me() is defined in protocol.h, so use it instead
of sock_owned_by_me().

Reviewed-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Geliang Tang <geliang.tang@suse.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2023-01-09 07:30:49 +00:00
Paolo Abeni fec3adfd75 mptcp: fix lockdep false positive
MattB reported a lockdep splat in the mptcp listener code cleanup:

 WARNING: possible circular locking dependency detected
 packetdrill/14278 is trying to acquire lock:
 ffff888017d868f0 ((work_completion)(&msk->work)){+.+.}-{0:0}, at: __flush_work (kernel/workqueue.c:3069)

 but task is already holding lock:
 ffff888017d84130 (sk_lock-AF_INET){+.+.}-{0:0}, at: mptcp_close (net/mptcp/protocol.c:2973)

 which lock already depends on the new lock.

 the existing dependency chain (in reverse order) is:

 -> #1 (sk_lock-AF_INET){+.+.}-{0:0}:
        __lock_acquire (kernel/locking/lockdep.c:5055)
        lock_acquire (kernel/locking/lockdep.c:466)
        lock_sock_nested (net/core/sock.c:3463)
        mptcp_worker (net/mptcp/protocol.c:2614)
        process_one_work (kernel/workqueue.c:2294)
        worker_thread (include/linux/list.h:292)
        kthread (kernel/kthread.c:376)
        ret_from_fork (arch/x86/entry/entry_64.S:312)

 -> #0 ((work_completion)(&msk->work)){+.+.}-{0:0}:
        check_prev_add (kernel/locking/lockdep.c:3098)
        validate_chain (kernel/locking/lockdep.c:3217)
        __lock_acquire (kernel/locking/lockdep.c:5055)
        lock_acquire (kernel/locking/lockdep.c:466)
        __flush_work (kernel/workqueue.c:3070)
        __cancel_work_timer (kernel/workqueue.c:3160)
        mptcp_cancel_work (net/mptcp/protocol.c:2758)
        mptcp_subflow_queue_clean (net/mptcp/subflow.c:1817)
        __mptcp_close_ssk (net/mptcp/protocol.c:2363)
        mptcp_destroy_common (net/mptcp/protocol.c:3170)
        mptcp_destroy (include/net/sock.h:1495)
        __mptcp_destroy_sock (net/mptcp/protocol.c:2886)
        __mptcp_close (net/mptcp/protocol.c:2959)
        mptcp_close (net/mptcp/protocol.c:2974)
        inet_release (net/ipv4/af_inet.c:432)
        __sock_release (net/socket.c:651)
        sock_close (net/socket.c:1367)
        __fput (fs/file_table.c:320)
        task_work_run (kernel/task_work.c:181 (discriminator 1))
        exit_to_user_mode_prepare (include/linux/resume_user_mode.h:49)
        syscall_exit_to_user_mode (kernel/entry/common.c:130)
        do_syscall_64 (arch/x86/entry/common.c:87)
        entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:120)

 other info that might help us debug this:

  Possible unsafe locking scenario:

        CPU0                    CPU1
        ----                    ----
   lock(sk_lock-AF_INET);
                                lock((work_completion)(&msk->work));
                                lock(sk_lock-AF_INET);
   lock((work_completion)(&msk->work));

  *** DEADLOCK ***

The report is actually a false positive, since the only existing lock
nesting is the msk socket lock acquired by the mptcp work.
cancel_work_sync() is invoked without the relevant socket lock being
held, but under a different (the msk listener) socket lock.

We could silence the splat adding a per workqueue dynamic lockdep key,
but that looks overkill. Instead just tell lockdep the msk socket lock
is not held around cancel_work_sync().

Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/322
Fixes: 30e51b923e ("mptcp: fix unreleased socket in accept queue")
Reported-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Reviewed-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-12-21 18:05:47 -08:00
Paolo Abeni 7d803344fd mptcp: fix deadlock in fastopen error path
MatM reported a deadlock at fastopening time:

INFO: task syz-executor.0:11454 blocked for more than 143 seconds.
      Tainted: G S                 6.1.0-rc5-03226-gdb0157db5153 #1
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.0  state:D stack:25104 pid:11454 ppid:424    flags:0x00004006
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5191 [inline]
 __schedule+0x5c2/0x1550 kernel/sched/core.c:6503
 schedule+0xe8/0x1c0 kernel/sched/core.c:6579
 __lock_sock+0x142/0x260 net/core/sock.c:2896
 lock_sock_nested+0xdb/0x100 net/core/sock.c:3466
 __mptcp_close_ssk+0x1a3/0x790 net/mptcp/protocol.c:2328
 mptcp_destroy_common+0x16a/0x650 net/mptcp/protocol.c:3171
 mptcp_disconnect+0xb8/0x450 net/mptcp/protocol.c:3019
 __inet_stream_connect+0x897/0xa40 net/ipv4/af_inet.c:720
 tcp_sendmsg_fastopen+0x3dd/0x740 net/ipv4/tcp.c:1200
 mptcp_sendmsg_fastopen net/mptcp/protocol.c:1682 [inline]
 mptcp_sendmsg+0x128a/0x1a50 net/mptcp/protocol.c:1721
 inet6_sendmsg+0x11f/0x150 net/ipv6/af_inet6.c:663
 sock_sendmsg_nosec net/socket.c:714 [inline]
 sock_sendmsg+0xf7/0x190 net/socket.c:734
 ____sys_sendmsg+0x336/0x970 net/socket.c:2476
 ___sys_sendmsg+0x122/0x1c0 net/socket.c:2530
 __sys_sendmmsg+0x18d/0x460 net/socket.c:2616
 __do_sys_sendmmsg net/socket.c:2645 [inline]
 __se_sys_sendmmsg net/socket.c:2642 [inline]
 __x64_sys_sendmmsg+0x9d/0x110 net/socket.c:2642
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x38/0x90 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7f5920a75e7d
RSP: 002b:00007f59201e8028 EFLAGS: 00000246 ORIG_RAX: 0000000000000133
RAX: ffffffffffffffda RBX: 00007f5920bb4f80 RCX: 00007f5920a75e7d
RDX: 0000000000000001 RSI: 0000000020002940 RDI: 0000000000000005
RBP: 00007f5920ae7593 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000020004050 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000000b R14: 00007f5920bb4f80 R15: 00007f59201c8000
 </TASK>

In the error path, tcp_sendmsg_fastopen() ends-up calling
mptcp_disconnect(), and the latter tries to close each
subflow, acquiring the socket lock on each of them.

At fastopen time, we have a single subflow, and such subflow
socket lock is already held by the called, causing the deadlock.

We already track the 'fastopen in progress' status inside the msk
socket. Use it to address the issue, making mptcp_disconnect() a
no op when invoked from the fastopen (error) path and doing the
relevant cleanup after releasing the subflow socket lock.

While at the above, rename the fastopen status bit to something
more meaningful.

Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/321
Fixes: fa9e57468a ("mptcp: fix abba deadlock on fastopen")
Reported-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Reviewed-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-12-21 18:05:39 -08:00
Paolo Abeni b11919e1bb Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Merge in the left-over fixes before the net-next pull-request.

net/mptcp/subflow.c
  d3295fee3c ("mptcp: use proper req destructor for IPv6")
  36b122baf6 ("mptcp: add subflow_v(4,6)_send_synack()")

Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2022-12-13 09:49:29 +01:00
Matthieu Baerts d3295fee3c mptcp: use proper req destructor for IPv6
Before, only the destructor from TCP request sock in IPv4 was called
even if the subflow was IPv6.

It is important to use the right destructor to avoid memory leaks with
some advanced IPv6 features, e.g. when the request socks contain
specific IPv6 options.

Fixes: 79c0949e9a ("mptcp: Add key generation and token tree")
Reviewed-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Cc: stable@vger.kernel.org
Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-12-12 13:11:24 -08:00
Matthieu Baerts 34b21d1ddc mptcp: dedicated request sock for subflow in v6
tcp_request_sock_ops structure is specific to IPv4. It should then not
be used with MPTCP subflows on top of IPv6.

For example, it contains the 'family' field, initialised to AF_INET.
This 'family' field is used by TCP FastOpen code to generate the cookie
but also by TCP Metrics, SELinux and SYN Cookies. Using the wrong family
will not lead to crashes but displaying/using/checking wrong things.

Note that 'send_reset' callback from request_sock_ops structure is used
in some error paths. It is then also important to use the correct one
for IPv4 or IPv6.

The slab name can also be different in IPv4 and IPv6, it will be used
when printing some log messages. The slab pointer will anyway be the
same because the object size is the same for both v4 and v6. A
BUILD_BUG_ON() has also been added to make sure this size is the same.

Fixes: cec37a6e41 ("mptcp: Handle MP_CAPABLE options for outgoing connections")
Reviewed-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Cc: stable@vger.kernel.org
Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-12-12 13:11:24 -08:00
Matthieu Baerts 3fff88186f mptcp: remove MPTCP 'ifdef' in TCP SYN cookies
To ease the maintenance, it is often recommended to avoid having #ifdef
preprocessor conditions.

Here the section related to CONFIG_MPTCP was quite short but the next
commit needs to add more code around. It is then cleaner to move
specific MPTCP code to functions located in net/mptcp directory.

Now that mptcp_subflow_request_sock_ops structure can be static, it can
also be marked as "read only after init".

Suggested-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Cc: stable@vger.kernel.org
Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-12-12 13:11:24 -08:00
Wei Yongjun e0fe1123ab mptcp: netlink: fix some error return code
Fix to return negative error code -EINVAL from some error handling
case instead of 0, as done elsewhere in those functions.

Fixes: 9ab4807c84 ("mptcp: netlink: Add MPTCP_PM_CMD_ANNOUNCE")
Fixes: 702c2f646d ("mptcp: netlink: allow userspace-driven subflow establishment")
Cc: stable@vger.kernel.org
Reviewed-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-12-12 13:11:23 -08:00
Matthieu Baerts 03e7d28cd2 mptcp: return 0 instead of 'err' var
When 'err' is 0, it looks clearer to return '0' instead of the variable
called 'err'.

The behaviour is then not modified, just a clearer code.

By doing this, we can also avoid false positive smatch warnings like
this one:

  net/mptcp/pm_netlink.c:1169 mptcp_pm_parse_pm_addr_attr() warn: missing error code? 'err'

Reported-by: kernel test robot <lkp@intel.com>
Reported-by: Dan Carpenter <error27@gmail.com>
Suggested-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Reviewed-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-12-09 19:46:11 -08:00
Geliang Tang 8b34b52c17 mptcp: use nlmsg_free instead of kfree_skb
Use nlmsg_free() instead of kfree_skb() in pm_netlink.c.

The SKB's have been created by nlmsg_new(). The proper cleaning way
should then be done with nlmsg_free().

For the moment, nlmsg_free() is simply calling kfree_skb() so we don't
change the behaviour here.

Suggested-by: Jakub Kicinski <kuba@kernel.org>
Reviewed-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Geliang Tang <geliang.tang@suse.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-12-09 19:46:11 -08:00
Geliang Tang f8c9dfbd87 mptcp: add pm listener events
This patch adds two new MPTCP netlink event types for PM listening
socket create and close, named MPTCP_EVENT_LISTENER_CREATED and
MPTCP_EVENT_LISTENER_CLOSED.

Add a new function mptcp_event_pm_listener() to push the new events
with family, port and addr to userspace.

Invoke mptcp_event_pm_listener() with MPTCP_EVENT_LISTENER_CREATED in
mptcp_listen() and mptcp_pm_nl_create_listen_socket(), invoke it with
MPTCP_EVENT_LISTENER_CLOSED in __mptcp_close_ssk().

Signed-off-by: Geliang Tang <geliang.tang@suse.com>
Reviewed-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-12-01 20:06:06 -08:00
Matthieu Baerts cb99816cb5 mptcp: add support for TCP_FASTOPEN_KEY sockopt
The goal of this socket option is to set different keys per listener,
see commit 1fba70e5b6 ("tcp: socket option to set TCP fast open key")
for more details about this socket option.

The only thing to do here with MPTCP is to relay the request to the
first subflow like it is already done for the other TCP_FASTOPEN* socket
options.

Acked-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-11-29 20:24:26 -08:00
Dmytro Shytyi 4ffb0a0234 mptcp: add TCP_FASTOPEN sock option
The TCP_FASTOPEN socket option is one way for the application to tell
the kernel TFO support has to be enabled for the listener socket.

The only thing to do here with MPTCP is to relay the request to the
first subflow like it is already done for the other TCP_FASTOPEN* socket
options.

Acked-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Dmytro Shytyi <dmytro@shytyi.net>
Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-11-29 20:24:25 -08:00
Dmytro Shytyi 36b122baf6 mptcp: add subflow_v(4,6)_send_synack()
The send_synack() needs to be overridden for MPTCP to support TFO for
two reasons:

- There is not be enough space in the TCP options if the TFO cookie has
  to be added in the SYN+ACK with other options: MSS (4), SACK OK (2),
  Timestamps (10), Window Scale (3+1), TFO (10+2), MP_CAPABLE (12).
  MPTCPv1 specs -- RFC 8684, section B.1 [1] -- suggest to drop the TCP
  timestamps option in this case.

- The data received in the SYN has to be handled: the SKB can be
  dequeued from the subflow sk and transferred to the MPTCP sk. Counters
  need to be updated accordingly and the application can be notified at
  the end because some bytes have been received.

[1] https://www.rfc-editor.org/rfc/rfc8684.html#section-b.1

Co-developed-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Co-developed-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Dmytro Shytyi <dmytro@shytyi.net>
Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-11-29 20:24:25 -08:00
Dmytro Shytyi dfc8d06030 mptcp: implement delayed seq generation for passive fastopen
With fastopen in place, the first subflow socket is created before the
MPC handshake completes, and we need to properly initialize the sequence
numbers at MPC ACK reception.

Co-developed-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Co-developed-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Dmytro Shytyi <dmytro@shytyi.net>
Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-11-29 20:24:25 -08:00
Paolo Abeni b3ea6b272d mptcp: consolidate initial ack seq generation
Currently the initial ack sequence is generated on demand whenever
it's requested and the remote key is handy. The relevant code is
scattered in different places and can lead to multiple, unneeded,
crypto operations.

This change consolidates the ack sequence generation code in a single
helper, storing the sequence number at the subflow level.

The above additionally saves a few conditional in fast-path and will
simplify the upcoming fast-open implementation.

Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-11-29 20:24:25 -08:00
Paolo Abeni fe33d38626 mptcp: track accurately the incoming MPC suboption type
Currently in the receive path we don't need to discriminate
between MPC SYN, MPC SYN-ACK and MPC ACK, but soon the fastopen
code will need that info to properly track the fully established
status.

Track the exact MPC suboption type into the receive opt bitmap.
No functional change intended.

Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-11-29 20:24:24 -08:00
Dmytro Shytyi 1e777f39b4 mptcp: add MSG_FASTOPEN sendmsg flag support
Since commit 54f1944ed6 ("mptcp: factor out mptcp_connect()"), all the
infrastructure is now in place to support the MSG_FASTOPEN flag, we
just need to call into the fastopen path in mptcp_sendmsg().

Co-developed-by: Benjamin Hesmans <benjamin.hesmans@tessares.net>
Signed-off-by: Benjamin Hesmans <benjamin.hesmans@tessares.net>
Acked-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Dmytro Shytyi <dmytro@shytyi.net>
Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-11-29 20:24:24 -08:00
Jakub Kicinski f2bb566f5c Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
tools/lib/bpf/ringbuf.c
  927cbb478a ("libbpf: Handle size overflow for ringbuf mmap")
  b486d19a0a ("libbpf: checkpatch: Fixed code alignments in ringbuf.c")
https://lore.kernel.org/all/20221121122707.44d1446a@canb.auug.org.au/

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-11-29 13:04:52 -08:00
Paolo Abeni b4f166651d mptcp: fix sleep in atomic at close time
Matt reported a splat at msk close time:

    BUG: sleeping function called from invalid context at net/mptcp/protocol.c:2877
    in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 155, name: packetdrill
    preempt_count: 201, expected: 0
    RCU nest depth: 0, expected: 0
    4 locks held by packetdrill/155:
    #0: ffff888001536990 (&sb->s_type->i_mutex_key#6){+.+.}-{3:3}, at: __sock_release (net/socket.c:650)
    #1: ffff88800b498130 (sk_lock-AF_INET){+.+.}-{0:0}, at: mptcp_close (net/mptcp/protocol.c:2973)
    #2: ffff88800b49a130 (sk_lock-AF_INET/1){+.+.}-{0:0}, at: __mptcp_close_ssk (net/mptcp/protocol.c:2363)
    #3: ffff88800b49a0b0 (slock-AF_INET){+...}-{2:2}, at: __lock_sock_fast (include/net/sock.h:1820)
    Preemption disabled at:
    0x0
    CPU: 1 PID: 155 Comm: packetdrill Not tainted 6.1.0-rc5 #365
    Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.15.0-1 04/01/2014
    Call Trace:
    <TASK>
    dump_stack_lvl (lib/dump_stack.c:107 (discriminator 4))
    __might_resched.cold (kernel/sched/core.c:9891)
    __mptcp_destroy_sock (include/linux/kernel.h:110)
    __mptcp_close (net/mptcp/protocol.c:2959)
    mptcp_subflow_queue_clean (include/net/sock.h:1777)
    __mptcp_close_ssk (net/mptcp/protocol.c:2363)
    mptcp_destroy_common (net/mptcp/protocol.c:3170)
    mptcp_destroy (include/net/sock.h:1495)
    __mptcp_destroy_sock (net/mptcp/protocol.c:2886)
    __mptcp_close (net/mptcp/protocol.c:2959)
    mptcp_close (net/mptcp/protocol.c:2974)
    inet_release (net/ipv4/af_inet.c:432)
    __sock_release (net/socket.c:651)
    sock_close (net/socket.c:1367)
    __fput (fs/file_table.c:320)
    task_work_run (kernel/task_work.c:181 (discriminator 1))
    exit_to_user_mode_prepare (include/linux/resume_user_mode.h:49)
    syscall_exit_to_user_mode (kernel/entry/common.c:130)
    do_syscall_64 (arch/x86/entry/common.c:87)
    entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:120)

We can't call mptcp_close under the 'fast' socket lock variant, replace
it with a sock_lock_nested() as the relevant code is already under the
listening msk socket lock protection.

Reported-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/316
Fixes: 30e51b923e ("mptcp: fix unreleased socket in accept queue")
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-11-28 18:03:07 -08:00
Menglong Dong fe94800184 mptcp: don't orphan ssk in mptcp_close()
All of the subflows of a msk will be orphaned in mptcp_close(), which
means the subflows are in DEAD state. After then, DATA_FIN will be sent,
and the other side will response with a DATA_ACK for this DATA_FIN.

However, if the other side still has pending data, the data that received
on these subflows will not be passed to the msk, as they are DEAD and
subflow_data_ready() will not be called in tcp_data_ready(). Therefore,
these data can't be acked, and they will be retransmitted again and again,
until timeout.

Fix this by setting ssk->sk_socket and ssk->sk_wq to 'NULL', instead of
orphaning the subflows in __mptcp_close(), as Paolo suggested.

Fixes: e16163b6e2 ("mptcp: refactor shutdown and close")
Reviewed-by: Biao Jiang <benbjiang@tencent.com>
Reviewed-by: Mengen Sun <mengensun@tencent.com>
Signed-off-by: Menglong Dong <imagedong@tencent.com>
Reviewed-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-11-28 18:03:07 -08:00
Paolo Abeni a3400e8746 mptcp: more detailed error reporting on endpoint creation
Endpoint creation can fail for a number of reasons; in case of failure
append the error number to the extended ack message, using a newly
introduced generic helper.

Additionally let mptcp_pm_nl_append_new_local_addr() report different
error reasons.

Reviewed-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
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>
2022-11-21 13:09:07 +00:00
Paolo Abeni 976d302fb6 mptcp: deduplicate error paths on endpoint creation
When endpoint creation fails, we need to free the newly allocated
entry and eventually destroy the paired mptcp listener socket.

Consolidate such action in a single point let all the errors path
reach it.

Reviewed-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
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>
2022-11-21 13:09:07 +00:00
Mat Martineau 4373bf4b72 mptcp: Fix grammar in a comment
We kept getting initial patches from new contributors to remove a
duplicate 'the' (since grammar checking scripts flag it), but submitters
never followed up after code review.

Reviewed-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-11-11 21:19:47 -08:00
Geliang Tang 80638684e8 mptcp: get sk from msk directly
Use '(struct sock *)msk' to get 'sk' from 'msk' in a more direct way
instead of using '&msk->sk.icsk_inet.sk'.

Reviewed-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Geliang Tang <geliang.tang@suse.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-11-11 21:19:47 -08:00
Geliang Tang 73a0052a61 mptcp: change 'first' as a parameter
The function mptcp_subflow_process_delegated() uses the input ssk first,
while __mptcp_check_push() invokes the packet scheduler first.

So this patch adds a new parameter named 'first' for the function
__mptcp_subflow_push_pending() to deal with these two cases separately.

With this change, the code that invokes the packet scheduler in the
function __mptcp_check_push() can be removed, and replaced by invoking
__mptcp_subflow_push_pending() directly.

Reviewed-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Geliang Tang <geliang.tang@suse.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-11-11 21:19:46 -08:00
Geliang Tang 00df24f191 mptcp: use msk instead of mptcp_sk
Use msk instead of mptcp_sk(sk) in the functions where the variable
"msk = mptcp_sk(sk)" has been defined.

Reviewed-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Geliang Tang <geliang.tang@suse.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-11-11 21:19:46 -08:00
Jakub Kicinski 31f1aa4f74 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
drivers/net/can/usb/kvaser_usb/kvaser_usb_leaf.c
  2871edb32f ("can: kvaser_usb: Fix possible completions during init_completion")
  abb8670938 ("can: kvaser_usb_leaf: Ignore stale bus-off after start")
  8d21f5927a ("can: kvaser_usb_leaf: Fix improved state not being reported")

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-10-27 16:56:36 -07:00
Eric Dumazet d1e96cc4fb mptcp: fix tracking issue in mptcp_subflow_create_socket()
My recent patch missed that mptcp_subflow_create_socket()
was creating a 'kernel' socket, then converted it to 'user' socket.

Fixes: 0cafd77dcd ("net: add a refcount tracker for kernel sockets")
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Matthieu Baerts <matthieu.baerts@tessares.net>
Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Reviewed-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Link: https://lore.kernel.org/r/20221025180546.652251-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-10-26 19:07:05 -07:00
Matthieu Baerts caea64675d mptcp: sockopt: use new helper for TCP_DEFER_ACCEPT
mptcp_setsockopt_sol_tcp_defer() was doing the same thing as
mptcp_setsockopt_first_sf_only() except for the returned code in case of
error.

Ignoring the error is needed to mimic how TCP_DEFER_ACCEPT is handled
when used with "plain" TCP sockets.

The specific function for TCP_DEFER_ACCEPT can be replaced by the new
mptcp_setsockopt_first_sf_only() helper and errors can be ignored to
stay compatible with TCP. A bit of cleanup.

Suggested-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Reviewed-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Acked-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2022-10-25 12:32:54 +02:00
Matthieu Baerts e64d4deb4d mptcp: add TCP_FASTOPEN_NO_COOKIE support
The goal of this socket option is to configure MPTCP + TFO without
cookie per socket.

It was already possible to enable TFO without a cookie per netns by
setting net.ipv4.tcp_fastopen sysctl knob to the right value. Per route
was also supported by setting 'fastopen_no_cookie' option. This patch
adds a per socket support like it is possible to do with TCP thanks to
TCP_FASTOPEN_NO_COOKIE socket option.

The only thing to do here is to relay the request to the first subflow
like it is already done for TCP_FASTOPEN_CONNECT.

Reviewed-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2022-10-25 12:32:54 +02:00
Matthieu Baerts d3d429047c mptcp: sockopt: make 'tcp_fastopen_connect' generic
There are other socket options that need to act only on the first
subflow, e.g. all TCP_FASTOPEN* socket options.

This is similar to the getsockopt version.

In the next commit, this new mptcp_setsockopt_first_sf_only() helper is
used by other another option.

Reviewed-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2022-10-25 12:32:54 +02:00
Paolo Abeni fa9e57468a mptcp: fix abba deadlock on fastopen
Our CI reported lockdep splat in the fastopen code:
 ======================================================
 WARNING: possible circular locking dependency detected
 6.0.0.mptcp_f5e8bfe9878d+ #1558 Not tainted
 ------------------------------------------------------
 packetdrill/1071 is trying to acquire lock:
 ffff8881bd198140 (sk_lock-AF_INET){+.+.}-{0:0}, at: inet_wait_for_connect+0x19c/0x310

 but task is already holding lock:
 ffff8881b8346540 (k-sk_lock-AF_INET){+.+.}-{0:0}, at: mptcp_sendmsg+0xfdf/0x1740

 which lock already depends on the new lock.

 the existing dependency chain (in reverse order) is:

 -> #1 (k-sk_lock-AF_INET){+.+.}-{0:0}:
        __lock_acquire+0xb6d/0x1860
        lock_acquire+0x1d8/0x620
        lock_sock_nested+0x37/0xd0
        inet_stream_connect+0x3f/0xa0
        mptcp_connect+0x411/0x800
        __inet_stream_connect+0x3ab/0x800
        mptcp_stream_connect+0xac/0x110
        __sys_connect+0x101/0x130
        __x64_sys_connect+0x6e/0xb0
        do_syscall_64+0x59/0x90
        entry_SYSCALL_64_after_hwframe+0x63/0xcd

 -> #0 (sk_lock-AF_INET){+.+.}-{0:0}:
        check_prev_add+0x15e/0x2110
        validate_chain+0xace/0xdf0
        __lock_acquire+0xb6d/0x1860
        lock_acquire+0x1d8/0x620
        lock_sock_nested+0x37/0xd0
        inet_wait_for_connect+0x19c/0x310
        __inet_stream_connect+0x26c/0x800
        tcp_sendmsg_fastopen+0x341/0x650
        mptcp_sendmsg+0x109d/0x1740
        sock_sendmsg+0xe1/0x120
        __sys_sendto+0x1c7/0x2a0
        __x64_sys_sendto+0xdc/0x1b0
        do_syscall_64+0x59/0x90
        entry_SYSCALL_64_after_hwframe+0x63/0xcd

 other info that might help us debug this:

  Possible unsafe locking scenario:

        CPU0                    CPU1
        ----                    ----
   lock(k-sk_lock-AF_INET);
                                lock(sk_lock-AF_INET);
                                lock(k-sk_lock-AF_INET);
   lock(sk_lock-AF_INET);

  *** DEADLOCK ***

 1 lock held by packetdrill/1071:
  #0: ffff8881b8346540 (k-sk_lock-AF_INET){+.+.}-{0:0}, at: mptcp_sendmsg+0xfdf/0x1740
 ======================================================

The problem is caused by the blocking inet_wait_for_connect() releasing
and re-acquiring the msk socket lock while the subflow socket lock is
still held and the MPTCP socket requires that the msk socket lock must
be acquired before the subflow socket lock.

Address the issue always invoking tcp_sendmsg_fastopen() in an
unblocking manner, and later eventually complete the blocking
__inet_stream_connect() as needed.

Fixes: d98a82a6af ("mptcp: handle defer connect in mptcp_sendmsg")
Reviewed-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Reviewed-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-10-24 21:13:56 -07:00
Paolo Abeni 54f1944ed6 mptcp: factor out mptcp_connect()
The current MPTCP connect implementation duplicates a bit of inet
code and does not use nor provide a struct proto->connect callback,
which in turn will not fit the upcoming fastopen implementation.

Refactor such implementation to use the common helper, moving the
MPTCP-specific bits into mptcp_connect(). Additionally, avoid an
indirect call to the subflow connect callback.

Note that the fastopen call-path invokes mptcp_connect() while already
holding the subflow socket lock. Explicitly keep track of such path
via a new MPTCP-level flag and handle the locking accordingly.

Additionally, track the connect flags in a new msk field to allow
propagating them to the subflow inet_stream_connect call.

Fixes: d98a82a6af ("mptcp: handle defer connect in mptcp_sendmsg")
Reviewed-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-10-24 21:13:55 -07:00
Paolo Abeni e72e403263 mptcp: set msk local address earlier
The mptcp_pm_nl_get_local_id() code assumes that the msk local address
is available at that point. For passive sockets, we initialize such
address at accept() time.

Depending on the running configuration and the user-space timing, a
passive MPJ subflow can join the msk socket before accept() completes.

In such case, the PM assigns a wrong local id to the MPJ subflow
and later PM netlink operations will end-up touching the wrong/unexpected
subflow.

All the above causes sporadic self-tests failures, especially when
the host is heavy loaded.

Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/308
Fixes: 01cacb00b3 ("mptcp: add netlink-based PM")
Fixes: d045b9eb95 ("mptcp: introduce implicit endpoints")
Reviewed-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-10-24 21:13:55 -07:00
Paolo Abeni a5ef058dc4 net: introduce and use custom sockopt socket flag
We will soon introduce custom setsockopt for UDP sockets, too.
Instead of doing even more complex arbitrary checks inside
sock_use_custom_sol_socket(), add a new socket flag and set it
for the relevant socket types (currently only MPTCP).

Reviewed-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Acked-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-10-24 10:52:50 +01:00
Kuniyuki Iwashima b5fc29233d inet6: Remove inet6_destroy_sock() in sk->sk_prot->destroy().
After commit d38afeec26 ("tcp/udp: Call inet6_destroy_sock()
in IPv6 sk->sk_destruct()."), we call inet6_destroy_sock() in
sk->sk_destruct() by setting inet6_sock_destruct() to it to make
sure we do not leak inet6-specific resources.

Now we can remove unnecessary inet6_destroy_sock() calls in
sk->sk_prot->destroy().

DCCP and SCTP have their own sk->sk_destruct() function, so we
change them separately in the following patches.

Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Reviewed-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-10-24 09:40:38 +01:00
Paolo Abeni d89e3ed76b mptcp: update misleading comments.
The MPTCP data path is quite complex and hard to understend even
without some foggy comments referring to modified code and/or
completely misleading from the beginning.

Update a few of them to more accurately describing the current
status.

Reviewed-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
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>
2022-10-03 11:18:53 +01:00
Paolo Abeni d21f834855 mptcp: use fastclose on more edge scenarios
Daire reported a user-space application hang-up when the
peer is forcibly closed before the data transfer completion.

The relevant application expects the peer to either
do an application-level clean shutdown or a transport-level
connection reset.

We can accommodate a such user by extending the fastclose
usage: at fd close time, if the msk socket has some unread
data, and at FIN_WAIT timeout.

Note that at MPTCP close time we must ensure that the TCP
subflows will reset: set the linger socket option to a suitable
value.

Reviewed-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Reviewed-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
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>
2022-10-03 11:18:53 +01:00
Paolo Abeni 69800e516e mptcp: propagate fastclose error
When an mptcp socket is closed due to an incoming FASTCLOSE
option, so specific sk_err is set and later syscall will
fail usually with EPIPE.

Align the current fastclose error handling with TCP reset,
properly setting the socket error according to the current
msk state and propagating such error.

Additionally sendmsg() is currently not handling properly
the sk_err, always returning EPIPE.

Reviewed-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Reviewed-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
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>
2022-10-03 11:18:53 +01:00
Jakub Kicinski accc3b4a57 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
No conflicts.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-09-29 14:30:51 -07:00
Menglong Dong 30e51b923e mptcp: fix unreleased socket in accept queue
The mptcp socket and its subflow sockets in accept queue can't be
released after the process exit.

While the release of a mptcp socket in listening state, the
corresponding tcp socket will be released too. Meanwhile, the tcp
socket in the unaccept queue will be released too. However, only init
subflow is in the unaccept queue, and the joined subflow is not in the
unaccept queue, which makes the joined subflow won't be released, and
therefore the corresponding unaccepted mptcp socket will not be released
to.

This can be reproduced easily with following steps:

1. create 2 namespace and veth:
   $ ip netns add mptcp-client
   $ ip netns add mptcp-server
   $ sysctl -w net.ipv4.conf.all.rp_filter=0
   $ ip netns exec mptcp-client sysctl -w net.mptcp.enabled=1
   $ ip netns exec mptcp-server sysctl -w net.mptcp.enabled=1
   $ ip link add red-client netns mptcp-client type veth peer red-server \
     netns mptcp-server
   $ ip -n mptcp-server address add 10.0.0.1/24 dev red-server
   $ ip -n mptcp-server address add 192.168.0.1/24 dev red-server
   $ ip -n mptcp-client address add 10.0.0.2/24 dev red-client
   $ ip -n mptcp-client address add 192.168.0.2/24 dev red-client
   $ ip -n mptcp-server link set red-server up
   $ ip -n mptcp-client link set red-client up

2. configure the endpoint and limit for client and server:
   $ ip -n mptcp-server mptcp endpoint flush
   $ ip -n mptcp-server mptcp limits set subflow 2 add_addr_accepted 2
   $ ip -n mptcp-client mptcp endpoint flush
   $ ip -n mptcp-client mptcp limits set subflow 2 add_addr_accepted 2
   $ ip -n mptcp-client mptcp endpoint add 192.168.0.2 dev red-client id \
     1 subflow

3. listen and accept on a port, such as 9999. The nc command we used
   here is modified, which makes it use mptcp protocol by default.
   $ ip netns exec mptcp-server nc -l -k -p 9999

4. open another *two* terminal and use each of them to connect to the
   server with the following command:
   $ ip netns exec mptcp-client nc 10.0.0.1 9999
   Input something after connect to trigger the connection of the second
   subflow. So that there are two established mptcp connections, with the
   second one still unaccepted.

5. exit all the nc command, and check the tcp socket in server namespace.
   And you will find that there is one tcp socket in CLOSE_WAIT state
   and can't release forever.

Fix this by closing all of the unaccepted mptcp socket in
mptcp_subflow_queue_clean() with __mptcp_close().

Now, we can ensure that all unaccepted mptcp sockets will be cleaned by
__mptcp_close() before they are released, so mptcp_sock_destruct(), which
is used to clean the unaccepted mptcp socket, is not needed anymore.

The selftests for mptcp is ran for this commit, and no new failures.

Fixes: f296234c98 ("mptcp: Add handling of incoming MP_JOIN requests")
Fixes: 6aeed90450 ("mptcp: fix race on unaccepted mptcp sockets")
Cc: stable@vger.kernel.org
Reviewed-by: Jiang Biao <benbjiang@tencent.com>
Reviewed-by: Mengen Sun <mengensun@tencent.com>
Acked-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Menglong Dong <imagedong@tencent.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-09-28 19:05:21 -07:00
Menglong Dong 26d3e21ce1 mptcp: factor out __mptcp_close() without socket lock
Factor out __mptcp_close() from mptcp_close(). The caller of
__mptcp_close() should hold the socket lock, and cancel mptcp work when
__mptcp_close() returns true.

This function will be used in the next commit.

Fixes: f296234c98 ("mptcp: Add handling of incoming MP_JOIN requests")
Fixes: 6aeed90450 ("mptcp: fix race on unaccepted mptcp sockets")
Cc: stable@vger.kernel.org
Reviewed-by: Jiang Biao <benbjiang@tencent.com>
Reviewed-by: Mengen Sun <mengensun@tencent.com>
Acked-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Menglong Dong <imagedong@tencent.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-09-28 19:05:21 -07:00
Benjamin Hesmans a42cf9d182 mptcp: poll allow write call before actual connect
If fastopen is used, poll must allow a first write that will trigger
the SYN+data

Similar to what is done in tcp_poll().

Acked-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Benjamin Hesmans <benjamin.hesmans@tessares.net>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-09-28 18:52:03 -07:00
Dmytro Shytyi d98a82a6af mptcp: handle defer connect in mptcp_sendmsg
When TCP_FASTOPEN_CONNECT has been set on the socket before a connect,
the defer flag is set and must be handled when sendmsg is called.

This is similar to what is done in tcp_sendmsg_locked().

Acked-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Co-developed-by: Benjamin Hesmans <benjamin.hesmans@tessares.net>
Signed-off-by: Benjamin Hesmans <benjamin.hesmans@tessares.net>
Signed-off-by: Dmytro Shytyi <dmytro@shytyi.net>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-09-28 18:52:03 -07:00
Benjamin Hesmans 54635bd047 mptcp: add TCP_FASTOPEN_CONNECT socket option
Set the option for the first subflow only. For the other subflows TFO
can't be used because a mapping would be needed to cover the data in the
SYN.

Acked-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Benjamin Hesmans <benjamin.hesmans@tessares.net>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-09-28 18:52:03 -07:00
Jakub Kicinski 0140a7168f Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
drivers/net/ethernet/freescale/fec.h
  7b15515fc1 ("Revert "fec: Restart PPS after link state change"")
  40c79ce13b ("net: fec: add stop mode support for imx8 platform")
https://lore.kernel.org/all/20220921105337.62b41047@canb.auug.org.au/

drivers/pinctrl/pinctrl-ocelot.c
  c297561bc9 ("pinctrl: ocelot: Fix interrupt controller")
  181f604b33 ("pinctrl: ocelot: add ability to be used in a non-mmio configuration")
https://lore.kernel.org/all/20220921110032.7cd28114@canb.auug.org.au/

tools/testing/selftests/drivers/net/bonding/Makefile
  bbb774d921 ("net: Add tests for bonding and team address list management")
  152e8ec776 ("selftests/bonding: add a test for bonding lladdr target")
https://lore.kernel.org/all/20220921110437.5b7dbd82@canb.auug.org.au/

drivers/net/can/usb/gs_usb.c
  5440428b3d ("can: gs_usb: gs_can_open(): fix race dev->can.state condition")
  45dfa45f52 ("can: gs_usb: add RX and TX hardware timestamp support")
https://lore.kernel.org/all/84f45a7d-92b6-4dc5-d7a1-072152fab6ff@tessares.net/

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-09-22 13:02:10 -07:00
Kuniyuki Iwashima 4461568aa4 tcp: Access &tcp_hashinfo via net.
We will soon introduce an optional per-netns ehash.

This means we cannot use tcp_hashinfo directly in most places.

Instead, access it via net->ipv4.tcp_death_row.hashinfo.

The access will be valid only while initialising tcp_hashinfo
itself and creating/destroying each netns.

Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-09-20 10:21:49 -07:00
Thomas Haller 3eb9a6b650 mptcp: account memory allocation in mptcp_nl_cmd_add_addr() to user
Now that non-root users can configure MPTCP endpoints, account
the memory allocation to the user.

Signed-off-by: Thomas Haller <thaller@redhat.com>
Reviewed-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2022-09-15 12:01:02 +02:00
Thomas Haller d156971854 mptcp: allow privileged operations from user namespaces
GENL_ADMIN_PERM checks that the user has CAP_NET_ADMIN in the initial
namespace by calling netlink_capable(). Instead, use GENL_UNS_ADMIN_PERM
which uses netlink_ns_capable(). This checks that the caller has
CAP_NET_ADMIN in the current user namespace.

See also

  commit 4a92602aa1 ("openvswitch: allow management from inside user namespaces")

which introduced this mechanism. See also

  commit 5617c6cd6f ("nl80211: Allow privileged operations from user namespaces")

which introduced this for nl80211.

Signed-off-by: Thomas Haller <thaller@redhat.com>
Reviewed-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2022-09-15 12:01:02 +02:00
Geliang Tang 0522b424c4 mptcp: add do_check_data_fin to replace copied
This patch adds a new bool variable 'do_check_data_fin' to replace the
original int variable 'copied' in __mptcp_push_pending(), check it to
determine whether to call __mptcp_check_send_data_fin().

Suggested-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Geliang Tang <geliang.tang@suse.com>
Reviewed-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2022-09-15 12:01:02 +02:00
Matthieu Baerts 5efbf6f7f0 mptcp: add mptcp_for_each_subflow_safe helper
Similar to mptcp_for_each_subflow(): this is clearer now that the _safe
version is used in multiple places.

Reviewed-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2022-09-15 12:01:02 +02:00
Paolo Abeni 7288ff6ec7 mptcp: fix fwd memory accounting on coalesce
The intel bot reported a memory accounting related splat:

[  240.473094] ------------[ cut here ]------------
[  240.478507] page_counter underflow: -4294828518 nr_pages=4294967290
[  240.485500] WARNING: CPU: 2 PID: 14986 at mm/page_counter.c:56 page_counter_cancel+0x96/0xc0
[  240.570849] CPU: 2 PID: 14986 Comm: mptcp_connect Tainted: G S                5.19.0-rc4-00739-gd24141fe7b48 #1
[  240.581637] Hardware name: HP HP Z240 SFF Workstation/802E, BIOS N51 Ver. 01.63 10/05/2017
[  240.590600] RIP: 0010:page_counter_cancel+0x96/0xc0
[  240.596179] Code: 00 00 00 45 31 c0 48 89 ef 5d 4c 89 c6 41 5c e9 40 fd ff ff 4c 89 e2 48 c7 c7 20 73 39 84 c6 05 d5 b1 52 04 01 e8 e7 95 f3
01 <0f> 0b eb a9 48 89 ef e8 1e 25 fc ff eb c3 66 66 2e 0f 1f 84 00 00
[  240.615639] RSP: 0018:ffffc9000496f7c8 EFLAGS: 00010082
[  240.621569] RAX: 0000000000000000 RBX: ffff88819c9c0120 RCX: 0000000000000000
[  240.629404] RDX: 0000000000000027 RSI: 0000000000000004 RDI: fffff5200092deeb
[  240.637239] RBP: ffff88819c9c0120 R08: 0000000000000001 R09: ffff888366527a2b
[  240.645069] R10: ffffed106cca4f45 R11: 0000000000000001 R12: 00000000fffffffa
[  240.652903] R13: ffff888366536118 R14: 00000000fffffffa R15: ffff88819c9c0000
[  240.660738] FS:  00007f3786e72540(0000) GS:ffff888366500000(0000) knlGS:0000000000000000
[  240.669529] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  240.675974] CR2: 00007f966b346000 CR3: 0000000168cea002 CR4: 00000000003706e0
[  240.683807] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[  240.691641] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[  240.699468] Call Trace:
[  240.702613]  <TASK>
[  240.705413]  page_counter_uncharge+0x29/0x80
[  240.710389]  drain_stock+0xd0/0x180
[  240.714585]  refill_stock+0x278/0x580
[  240.718951]  __sk_mem_reduce_allocated+0x222/0x5c0
[  240.729248]  __mptcp_update_rmem+0x235/0x2c0
[  240.734228]  __mptcp_move_skbs+0x194/0x6c0
[  240.749764]  mptcp_recvmsg+0xdfa/0x1340
[  240.763153]  inet_recvmsg+0x37f/0x500
[  240.782109]  sock_read_iter+0x24a/0x380
[  240.805353]  new_sync_read+0x420/0x540
[  240.838552]  vfs_read+0x37f/0x4c0
[  240.842582]  ksys_read+0x170/0x200
[  240.864039]  do_syscall_64+0x5c/0x80
[  240.872770]  entry_SYSCALL_64_after_hwframe+0x46/0xb0
[  240.878526] RIP: 0033:0x7f3786d9ae8e
[  240.882805] Code: c0 e9 b6 fe ff ff 50 48 8d 3d 6e 18 0a 00 e8 89 e8 01 00 66 0f 1f 84 00 00 00 00 00 64 8b 04 25 18 00 00 00 85 c0 75 14 0f 05 <48> 3d 00 f0 ff ff 77 5a c3 66 0f 1f 84 00 00 00 00 00 48 83 ec 28
[  240.902259] RSP: 002b:00007fff7be81e08 EFLAGS: 00000246 ORIG_RAX: 0000000000000000
[  240.910533] RAX: ffffffffffffffda RBX: 0000000000002000 RCX: 00007f3786d9ae8e
[  240.918368] RDX: 0000000000002000 RSI: 00007fff7be87ec0 RDI: 0000000000000005
[  240.926206] RBP: 0000000000000005 R08: 00007f3786e6a230 R09: 00007f3786e6a240
[  240.934046] R10: fffffffffffff288 R11: 0000000000000246 R12: 0000000000002000
[  240.941884] R13: 00007fff7be87ec0 R14: 00007fff7be87ec0 R15: 0000000000002000
[  240.949741]  </TASK>
[  240.952632] irq event stamp: 27367
[  240.956735] hardirqs last  enabled at (27366): [<ffffffff81ba50ea>] mem_cgroup_uncharge_skmem+0x6a/0x80
[  240.966848] hardirqs last disabled at (27367): [<ffffffff81b8fd42>] refill_stock+0x282/0x580
[  240.976017] softirqs last  enabled at (27360): [<ffffffff83a4d8ef>] mptcp_recvmsg+0xaf/0x1340
[  240.985273] softirqs last disabled at (27364): [<ffffffff83a4d30c>] __mptcp_move_skbs+0x18c/0x6c0
[  240.994872] ---[ end trace 0000000000000000 ]---

After commit d24141fe7b ("mptcp: drop SK_RECLAIM_* macros"),
if rmem_fwd_alloc become negative, mptcp_rmem_uncharge() can
try to reclaim a negative amount of pages, since the expression:

	reclaimable >= PAGE_SIZE

will evaluate to true for any negative value of the int
'reclaimable': 'PAGE_SIZE' is an unsigned long and
the negative integer will be promoted to a (very large)
unsigned long value.

Still after the mentioned commit, kfree_skb_partial()
in mptcp_try_coalesce() will reclaim most of just released fwd
memory, so that following charging of the skb delta size will
lead to negative fwd memory values.

At that point a racing recvmsg() can trigger the splat.

Address the issue switching the order of the memory accounting
operations. The fwd memory can still transiently reach negative
values, but that will happen in an atomic scope and no code
path could touch/use such value.

Reported-by: kernel test robot <oliver.sang@intel.com>
Fixes: d24141fe7b ("mptcp: drop SK_RECLAIM_* macros")
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Link: https://lore.kernel.org/r/20220906180404.1255873-1-matthieu.baerts@tessares.net
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2022-09-13 10:18:44 +02:00
Jakub Kicinski 9c5d03d362 genetlink: start to validate reserved header bytes
We had historically not checked that genlmsghdr.reserved
is 0 on input which prevents us from using those precious
bytes in the future.

One use case would be to extend the cmd field, which is
currently just 8 bits wide and 256 is not a lot of commands
for some core families.

To make sure that new families do the right thing by default
put the onus of opting out of validation on existing families.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Acked-by: Paul Moore <paul@paul-moore.com> (NetLabel)
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-08-29 12:47:15 +01:00
Kuniyuki Iwashima 657b991afb net: Fix data-races around sysctl_max_skb_frags.
While reading sysctl_max_skb_frags, it can be changed concurrently.
Thus, we need to add READ_ONCE() to its readers.

Fixes: 5f74f82ea3 ("net:Add sysctl_max_skb_frags")
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-08-24 13:46:58 +01:00
Paolo Abeni c886d70286 mptcp: do not queue data on closed subflows
Dipanjan reported a syzbot splat at close time:

WARNING: CPU: 1 PID: 10818 at net/ipv4/af_inet.c:153
inet_sock_destruct+0x6d0/0x8e0 net/ipv4/af_inet.c:153
Modules linked in: uio_ivshmem(OE) uio(E)
CPU: 1 PID: 10818 Comm: kworker/1:16 Tainted: G           OE
5.19.0-rc6-g2eae0556bb9d #2
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS
1.13.0-1ubuntu1.1 04/01/2014
Workqueue: events mptcp_worker
RIP: 0010:inet_sock_destruct+0x6d0/0x8e0 net/ipv4/af_inet.c:153
Code: 21 02 00 00 41 8b 9c 24 28 02 00 00 e9 07 ff ff ff e8 34 4d 91
f9 89 ee 4c 89 e7 e8 4a 47 60 ff e9 a6 fc ff ff e8 20 4d 91 f9 <0f> 0b
e9 84 fe ff ff e8 14 4d 91 f9 0f 0b e9 d4 fd ff ff e8 08 4d
RSP: 0018:ffffc9001b35fa78 EFLAGS: 00010246
RAX: 0000000000000000 RBX: 00000000002879d0 RCX: ffff8881326f3b00
RDX: 0000000000000000 RSI: ffff8881326f3b00 RDI: 0000000000000002
RBP: ffff888179662674 R08: ffffffff87e983a0 R09: 0000000000000000
R10: 0000000000000005 R11: 00000000000004ea R12: ffff888179662400
R13: ffff888179662428 R14: 0000000000000001 R15: ffff88817e38e258
FS:  0000000000000000(0000) GS:ffff8881f5f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000020007bc0 CR3: 0000000179592000 CR4: 0000000000150ee0
Call Trace:
 <TASK>
 __sk_destruct+0x4f/0x8e0 net/core/sock.c:2067
 sk_destruct+0xbd/0xe0 net/core/sock.c:2112
 __sk_free+0xef/0x3d0 net/core/sock.c:2123
 sk_free+0x78/0xa0 net/core/sock.c:2134
 sock_put include/net/sock.h:1927 [inline]
 __mptcp_close_ssk+0x50f/0x780 net/mptcp/protocol.c:2351
 __mptcp_destroy_sock+0x332/0x760 net/mptcp/protocol.c:2828
 mptcp_worker+0x5d2/0xc90 net/mptcp/protocol.c:2586
 process_one_work+0x9cc/0x1650 kernel/workqueue.c:2289
 worker_thread+0x623/0x1070 kernel/workqueue.c:2436
 kthread+0x2e9/0x3a0 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:302
 </TASK>

The root cause of the problem is that an mptcp-level (re)transmit can
race with mptcp_close() and the packet scheduler checks the subflow
state before acquiring the socket lock: we can try to (re)transmit on
an already closed ssk.

Fix the issue checking again the subflow socket status under the
subflow socket lock protection. Additionally add the missing check
for the fallback-to-tcp case.

Fixes: d5f49190de ("mptcp: allow picking different xmit subflows")
Reported-by: Dipanjan Das <mail.dipanjan.das@gmail.com>
Reviewed-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
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>
2022-08-05 08:51:28 +01:00
Paolo Abeni c0bf3c6aa4 mptcp: move subflow cleanup in mptcp_destroy_common()
If the mptcp socket creation fails due to a CGROUP_INET_SOCK_CREATE
eBPF program, the MPTCP protocol ends-up leaking all the subflows:
the related cleanup happens in __mptcp_destroy_sock() that is not
invoked in such code path.

Address the issue moving the subflow sockets cleanup in the
mptcp_destroy_common() helper, which is invoked in every msk cleanup
path.

Additionally get rid of the intermediate list_splice_init step, which
is an unneeded relic from the past.

The issue is present since before the reported root cause commit, but
any attempt to backport the fix before that hash will require a complete
rewrite.

Fixes: e16163b6e2 ("mptcp: refactor shutdown and close")
Reported-by: Nguyen Dinh Phi <phind.uet@gmail.com>
Reviewed-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Co-developed-by: Nguyen Dinh Phi <phind.uet@gmail.com>
Signed-off-by: Nguyen Dinh Phi <phind.uet@gmail.com>
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>
2022-08-05 08:51:28 +01:00
Jakub Kicinski 272ac32f56 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
No conflicts.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-07-28 18:21:16 -07:00
Mat Martineau b5177ed92b mptcp: Do not return EINPROGRESS when subflow creation succeeds
New subflows are created within the kernel using O_NONBLOCK, so
EINPROGRESS is the expected return value from kernel_connect().
__mptcp_subflow_connect() has the correct logic to consider EINPROGRESS
to be a successful case, but it has also used that error code as its
return value.

Before v5.19 this was benign: all the callers ignored the return
value. Starting in v5.19 there is a MPTCP_PM_CMD_SUBFLOW_CREATE generic
netlink command that does use the return value, so the EINPROGRESS gets
propagated to userspace.

Make __mptcp_subflow_connect() always return 0 on success instead.

Fixes: ec3edaa7ca ("mptcp: Add handling of outgoing MP_JOIN requests")
Fixes: 702c2f646d ("mptcp: netlink: allow userspace-driven subflow establishment")
Acked-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Link: https://lore.kernel.org/r/20220725205231.87529-1-mathew.j.martineau@linux.intel.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-07-26 19:57:55 -07:00
Kuniyuki Iwashima 0273954595 net: Fix data-races around sysctl_[rw]mem(_offset)?.
While reading these sysctl variables, they can be changed concurrently.
Thus, we need to add READ_ONCE() to their readers.

  - .sysctl_rmem
  - .sysctl_rwmem
  - .sysctl_rmem_offset
  - .sysctl_wmem_offset
  - sysctl_tcp_rmem[1, 2]
  - sysctl_tcp_wmem[1, 2]
  - sysctl_decnet_rmem[1]
  - sysctl_decnet_wmem[1]
  - sysctl_tipc_rmem[1]

Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-07-25 12:42:09 +01:00
Kuniyuki Iwashima 0f1e4d0659 tcp: Fix data-races around sysctl_tcp_workaround_signed_windows.
While reading sysctl_tcp_workaround_signed_windows, it can be changed
concurrently.  Thus, we need to add READ_ONCE() to its readers.

Fixes: 15d99e02ba ("[TCP]: sysctl to allow TCP window > 32767 sans wscale")
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-07-22 12:06:17 +01:00
Kuniyuki Iwashima 7804764888 tcp: Fix data-races around sysctl_tcp_moderate_rcvbuf.
While reading sysctl_tcp_moderate_rcvbuf, it can be changed
concurrently.  Thus, we need to add READ_ONCE() to its readers.

Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-07-22 12:06:17 +01:00
Jakub Kicinski 816cd16883 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
include/net/sock.h
  310731e2f1 ("net: Fix data-races around sysctl_mem.")
  e70f3c7012 ("Revert "net: set SK_MEM_QUANTUM to 4096"")
https://lore.kernel.org/all/20220711120211.7c8b7cba@canb.auug.org.au/

net/ipv4/fib_semantics.c
  747c143072 ("ip: fix dflt addr selection for connected nexthop")
  d62607c3fe ("net: rename reference+tracking helpers")

net/tls/tls.h
include/net/tls.h
  3d8c51b25a ("net/tls: Check for errors in tls_device_init")
  5879031423 ("tls: create an internal header")

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-07-14 15:27:35 -07:00
Paolo Abeni 3ad14f54bd mptcp: more accurate MPC endpoint tracking
Currently the id accounting for the ID 0 subflow is not correct:
at creation time we mark (correctly) as unavailable the endpoint
id corresponding the MPC subflow source address, while at subflow
removal time set as available the id 0.

With this change we track explicitly the endpoint id corresponding
to the MPC subflow so that we can mark it as available at removal time.
Additionally this allow deleting the initial subflow via the NL PM
specifying the corresponding endpoint id.

Reviewed-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-07-12 18:37:20 -07:00
Paolo Abeni c157bbe776 mptcp: allow the in kernel PM to set MPC subflow priority
Any local endpoints configured on the address matching the
MPC subflow are currently ignored.

Specifically, setting a backup flag on them has no effect
on the first subflow, as the MPC handshake can't carry such
info.

This change refactors the MPC endpoint id accounting to
additionally fetch the priority info from the relevant endpoint
and eventually trigger the MP_PRIO handshake as needed.

As a result, the MPC subflow now switches to backup priority
after that the MPTCP socket is fully established, according
to the local endpoint configuration.

Reviewed-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-07-12 18:37:19 -07:00
Paolo Abeni bedee0b561 mptcp: address lookup improvements
When looking-up a socket address in the endpoint list, we
must prefer port-based matches over address only match.

Ensure that port-based endpoints are listed first, using
head insertion for them. Additionally be sure that only
port-based endpoints carry a non zero port number.

Reviewed-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-07-12 18:37:19 -07:00
Paolo Abeni f5360e9b31 mptcp: introduce and use mptcp_pm_send_ack()
The in-kernel PM has a bit of duplicate code related to ack
generation. Create a new helper factoring out the PM-specific
needs and use it in a couple of places.

As a bonus, mptcp_subflow_send_ack() is not used anymore
outside its own compilation unit and can become static.

Reviewed-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-07-12 18:37:19 -07:00
Paolo Abeni 5c835bb142 mptcp: fix subflow traversal at disconnect time
At disconnect time the MPTCP protocol traverse the subflows
list closing each of them. In some circumstances - MPJ subflow,
passive MPTCP socket, the latter operation can remove the
subflow from the list, invalidating the current iterator.

Address the issue using the safe list traversing helper
variant.

Reported-by: van fantasy <g1042620637@gmail.com>
Fixes: b29fcfb54c ("mptcp: full disconnect implementation")
Tested-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Reviewed-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
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>
2022-07-11 11:31:38 +01:00
Geliang Tang f7657ff4a7 mptcp: move MPTCPOPT_HMAC_LEN to net/mptcp.h
Move macro MPTCPOPT_HMAC_LEN definition from net/mptcp/protocol.h to
include/net/mptcp.h.

Reviewed-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Geliang Tang <geliang.tang@suse.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-07-09 12:19:23 +01:00
Jakub Kicinski 83ec88d81a Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
No conflicts.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-07-07 12:07:37 -07:00
Geliang Tang d2d21f175f mptcp: update MIB_RMSUBFLOW in cmd_sf_destroy
This patch increases MPTCP_MIB_RMSUBFLOW mib counter in userspace pm
destroy subflow function mptcp_nl_cmd_sf_destroy() when removing subflow.

Fixes: 702c2f646d ("mptcp: netlink: allow userspace-driven subflow establishment")
Signed-off-by: Geliang Tang <geliang.tang@suse.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-07-06 12:50:26 +01:00
Paolo Abeni 843b5e75ef mptcp: fix local endpoint accounting
In mptcp_pm_nl_rm_addr_or_subflow() we always mark as available
the id corresponding to the just removed address.

The used bitmap actually tracks only the local IDs: we must
restrict the operation when a (local) subflow is removed.

Fixes: a88c9e4969 ("mptcp: do not block subflows creation on errors")
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>
2022-07-06 12:50:26 +01:00
Kishen Maloor 892f396c8e mptcp: netlink: issue MP_PRIO signals from userspace PMs
This change updates MPTCP_PM_CMD_SET_FLAGS to allow userspace PMs
to issue MP_PRIO signals over a specific subflow selected by
the connection token, local and remote address+port.

Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/286
Fixes: 702c2f646d ("mptcp: netlink: allow userspace-driven subflow establishment")
Acked-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Kishen Maloor <kishen.maloor@intel.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-07-06 12:50:26 +01:00
Mat Martineau a657430260 mptcp: Acquire the subflow socket lock before modifying MP_PRIO flags
When setting up a subflow's flags for sending MP_PRIO MPTCP options, the
subflow socket lock was not held while reading and modifying several
struct members that are also read and modified in mptcp_write_options().

Acquire the subflow socket lock earlier and send the MP_PRIO ACK with
that lock already acquired. Add a new variant of the
mptcp_subflow_send_ack() helper to use with the subflow lock held.

Fixes: 067065422f ("mptcp: add the outgoing MP_PRIO support")
Acked-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>
2022-07-06 12:50:26 +01:00
Mat Martineau c21b50d591 mptcp: Avoid acquiring PM lock for subflow priority changes
The in-kernel path manager code for changing subflow flags acquired both
the msk socket lock and the PM lock when possibly changing the "backup"
and "fullmesh" flags. mptcp_pm_nl_mp_prio_send_ack() does not access
anything protected by the PM lock, and it must release and reacquire
the PM lock.

By pushing the PM lock to where it is needed in mptcp_pm_nl_fullmesh(),
the lock is only acquired when the fullmesh flag is changed and the
backup flag code no longer has to release and reacquire the PM lock. The
change in locking context requires the MIB update to be modified - move
that to a better location instead.

This change also makes it possible to call
mptcp_pm_nl_mp_prio_send_ack() for the userspace PM commands without
manipulating the in-kernel PM lock.

Fixes: 0f9f696a50 ("mptcp: add set_flags command in PM netlink")
Acked-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>
2022-07-06 12:50:26 +01:00
Paolo Abeni 5ccecaec5c mptcp: fix locking in mptcp_nl_cmd_sf_destroy()
The user-space PM subflow removal path uses a couple of helpers
that must be called under the msk socket lock and the current
code lacks such requirement.

Change the existing lock scope so that the relevant code is under
its protection.

Fixes: 702c2f646d ("mptcp: netlink: allow userspace-driven subflow establishment")
Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/287
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>
2022-07-06 12:50:26 +01:00
Paolo Abeni 69d93daec0 mptcp: refine memory scheduling
Similar to commit 7c80b038d2 ("net: fix sk_wmem_schedule() and
sk_rmem_schedule() errors"), let the MPTCP receive path schedule
exactly the required amount of memory.

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>
2022-07-01 13:24:59 +01:00
Paolo Abeni d24141fe7b mptcp: drop SK_RECLAIM_* macros
After commit 4890b686f4 ("net: keep sk->sk_forward_alloc as small as
possible"), the MPTCP protocol is the last SK_RECLAIM_CHUNK and
SK_RECLAIM_THRESHOLD users.

Update the MPTCP reclaim schema to match the core/TCP one and drop the
mentioned macros. This additionally clean the MPTCP code a bit.

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>
2022-07-01 13:24:59 +01:00
Paolo Abeni 4aaa1685f7 mptcp: never fetch fwd memory from the subflow
The memory accounting is broken in such exceptional code
path, and after commit 4890b686f4 ("net: keep sk->sk_forward_alloc
as small as possible") we can't find much help there.

Drop the broken code.

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>
2022-07-01 13:24:59 +01:00
Jakub Kicinski 0d8730f07c Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
drivers/net/ethernet/microchip/sparx5/sparx5_switchdev.c
  9c5de246c1 ("net: sparx5: mdb add/del handle non-sparx5 devices")
  fbb89d02e3 ("net: sparx5: Allow mdb entries to both CPU and ports")

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-06-30 16:31:00 -07:00
Menglong Dong d640516a65 net: mptcp: fix some spelling mistake in mptcp
codespell finds some spelling mistake in mptcp:

net/mptcp/subflow.c:1624: interaces ==> interfaces
net/mptcp/pm_netlink.c:1130: regarless ==> regardless

Just fix them.

Signed-off-by: Menglong Dong <imagedong@tencent.com>
Reviewed-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Link: https://lore.kernel.org/r/20220627121626.1595732-1-imagedong@tencent.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-06-28 22:11:45 -07:00
Paolo Abeni 6aeed90450 mptcp: fix race on unaccepted mptcp sockets
When the listener socket owning the relevant request is closed,
it frees the unaccepted subflows and that causes later deletion
of the paired MPTCP sockets.

The mptcp socket's worker can run in the time interval between such delete
operations. When that happens, any access to msk->first will cause an UaF
access, as the subflow cleanup did not cleared such field in the mptcp
socket.

Address the issue explicitly traversing the listener socket accept
queue at close time and performing the needed cleanup on the pending
msk.

Note that the locking is a bit tricky, as we need to acquire the msk
socket lock, while still owning the subflow socket one.

Fixes: 86e39e0448 ("mptcp: keep track of local endpoint still available for each msk")
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-06-28 20:45:42 -07:00
Paolo Abeni f745a3ebdf mptcp: consistent map handling on failure
When the MPTCP receive path reach a non fatal fall-back condition, e.g.
when the MPC sockets must fall-back to TCP, the existing code is a little
self-inconsistent: it reports that new data is available - return true -
but sets the MPC flag to the opposite value.

As the consequence read operations in some exceptional scenario may block
unexpectedly.

Address the issue setting the correct MPC read status. Additionally avoid
some code duplication in the fatal fall-back scenario.

Fixes: 9c81be0dbc ("mptcp: add MP_FAIL response support")
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-06-28 20:45:42 -07:00
Paolo Abeni d51991e2e3 mptcp: fix shutdown vs fallback race
If the MPTCP socket shutdown happens before a fallback
to TCP, and all the pending data have been already spooled,
we never close the TCP connection.

Address the issue explicitly checking for critical condition
at fallback time.

Fixes: 1e39e5a32a ("mptcp: infinite mapping sending")
Fixes: 0348c690ed ("mptcp: add the fallback check")
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-06-28 20:45:42 -07:00
Geliang Tang 76a13b3157 mptcp: invoke MP_FAIL response when needed
mptcp_mp_fail_no_response shouldn't be invoked on each worker run, it
should be invoked only when MP_FAIL response timeout occurs.

This patch refactors the MP_FAIL response logic.

It leverages the fact that only the MPC/first subflow can gracefully
fail to avoid unneeded subflows traversal: the failing subflow can
be only msk->first.

A new 'fail_tout' field is added to the subflow context to record the
MP_FAIL response timeout and use such field to reliably share the
timeout timer between the MP_FAIL event and the MPTCP socket close
timeout.

Finally, a new ack is generated to send out MP_FAIL notification as soon
as we hit the relevant condition, instead of waiting a possibly unbound
time for the next data packet.

Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/281
Fixes: d9fb797046 ("mptcp: Do not traverse the subflow connection list without lock")
Co-developed-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Geliang Tang <geliang.tang@suse.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-06-28 20:45:42 -07:00
Paolo Abeni 31bf11de14 mptcp: introduce MAPPING_BAD_CSUM
This allow moving a couple of conditional out of the fast path,
making the code more easy to follow and will simplify the next
patch.

Fixes: ae66fb2ba6 ("mptcp: Do TCP fallback on early DSS checksum failure")
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-06-28 20:45:42 -07:00
Paolo Abeni 0c1f78a49a mptcp: fix error mibs accounting
The current accounting for MP_FAIL and FASTCLOSE is not very
accurate: both can be increased even when the related option is
not really sent. Move the accounting into the correct place.

Fixes: eb7f33654d ("mptcp: add the mibs for MP_FAIL")
Fixes: 1e75629cb9 ("mptcp: add the mibs for MP_FASTCLOSE")
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-06-28 20:45:42 -07:00
Eric Dumazet 4890b686f4 net: keep sk->sk_forward_alloc as small as possible
Currently, tcp_memory_allocated can hit tcp_mem[] limits quite fast.

Each TCP socket can forward allocate up to 2 MB of memory, even after
flow became less active.

10,000 sockets can have reserved 20 GB of memory,
and we have no shrinker in place to reclaim that.

Instead of trying to reclaim the extra allocations in some places,
just keep sk->sk_forward_alloc values as small as possible.

This should not impact performance too much now we have per-cpu
reserves: Changes to tcp_memory_allocated should not be too frequent.

For sockets not using SO_RESERVE_MEM:
 - idle sockets (no packets in tx/rx queues) have zero forward alloc.
 - non idle sockets have a forward alloc smaller than one page.

Note:

 - Removal of SK_RECLAIM_CHUNK and SK_RECLAIM_THRESHOLD
   is left to MPTCP maintainers as a follow up.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Shakeel Butt <shakeelb@google.com>
Acked-by: Soheil Hassas Yeganeh <soheil@google.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-06-10 16:21:27 -07:00
Eric Dumazet 0defbb0af7 net: add per_cpu_fw_alloc field to struct proto
Each protocol having a ->memory_allocated pointer gets a corresponding
per-cpu reserve, that following patches will use.

Instead of having reserved bytes per socket,
we want to have per-cpu reserves.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Shakeel Butt <shakeelb@google.com>
Acked-by: Soheil Hassas Yeganeh <soheil@google.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-06-10 16:21:26 -07:00
Eric Dumazet 100fdd1faf net: remove SK_MEM_QUANTUM and SK_MEM_QUANTUM_SHIFT
Due to memcg interface, SK_MEM_QUANTUM is effectively PAGE_SIZE.

This might change in the future, but it seems better to avoid the
confusion.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Shakeel Butt <shakeelb@google.com>
Acked-by: Soheil Hassas Yeganeh <soheil@google.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-06-10 16:21:26 -07:00
Jakub Kicinski 1ef0736c07 Merge https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next
Daniel Borkmann says:

====================
pull-request: bpf-next 2022-05-23

We've added 113 non-merge commits during the last 26 day(s) which contain
a total of 121 files changed, 7425 insertions(+), 1586 deletions(-).

The main changes are:

1) Speed up symbol resolution for kprobes multi-link attachments, from Jiri Olsa.

2) Add BPF dynamic pointer infrastructure e.g. to allow for dynamically sized ringbuf
   reservations without extra memory copies, from Joanne Koong.

3) Big batch of libbpf improvements towards libbpf 1.0 release, from Andrii Nakryiko.

4) Add BPF link iterator to traverse links via seq_file ops, from Dmitrii Dolgov.

5) Add source IP address to BPF tunnel key infrastructure, from Kaixi Fan.

6) Refine unprivileged BPF to disable only object-creating commands, from Alan Maguire.

7) Fix JIT blinding of ld_imm64 when they point to subprogs, from Alexei Starovoitov.

8) Add BPF access to mptcp_sock structures and their meta data, from Geliang Tang.

9) Add new BPF helper for access to remote CPU's BPF map elements, from Feng Zhou.

10) Allow attaching 64-bit cookie to BPF link of fentry/fexit/fmod_ret, from Kui-Feng Lee.

11) Follow-ups to typed pointer support in BPF maps, from Kumar Kartikeya Dwivedi.

12) Add busy-poll test cases to the XSK selftest suite, from Magnus Karlsson.

13) Improvements in BPF selftest test_progs subtest output, from Mykola Lysenko.

14) Fill bpf_prog_pack allocator areas with illegal instructions, from Song Liu.

15) Add generic batch operations for BPF map-in-map cases, from Takshak Chahande.

16) Make bpf_jit_enable more user friendly when permanently on 1, from Tiezhu Yang.

17) Fix an array overflow in bpf_trampoline_get_progs(), from Yuntao Wang.

====================

Link: https://lore.kernel.org/r/20220523223805.27931-1-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-05-23 16:07:14 -07:00
Geliang Tang 3bc253c2e6 bpf: Add bpf_skc_to_mptcp_sock_proto
This patch implements a new struct bpf_func_proto, named
bpf_skc_to_mptcp_sock_proto. Define a new bpf_id BTF_SOCK_TYPE_MPTCP,
and a new helper bpf_skc_to_mptcp_sock(), which invokes another new
helper bpf_mptcp_sock_from_subflow() in net/mptcp/bpf.c to get struct
mptcp_sock from a given subflow socket.

v2: Emit BTF type, add func_id checks in verifier.c and bpf_trace.c,
remove build check for CONFIG_BPF_JIT
v5: Drop EXPORT_SYMBOL (Martin)

Co-developed-by: Nicolas Rybowski <nicolas.rybowski@tessares.net>
Co-developed-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Nicolas Rybowski <nicolas.rybowski@tessares.net>
Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Geliang Tang <geliang.tang@suse.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20220519233016.105670-2-mathew.j.martineau@linux.intel.com
2022-05-20 15:29:00 -07:00
Mat Martineau d9fb797046 mptcp: Do not traverse the subflow connection list without lock
The MPTCP socket's conn_list (list of subflows) requires the socket lock
to access. The MP_FAIL timeout code added such an access, where it would
check the list of subflows both in timer context and (later) in workqueue
context where the socket lock is held.

Rather than check the list twice, remove the check in the timeout
handler and only depend on the check in the workqueue. Also remove the
MPTCP_FAIL_NO_RESPONSE flag, since mptcp_mp_fail_no_response() has
insignificant overhead and can be checked on each worker run.

Fixes: 49fa1919d6 ("mptcp: reset subflow when MP_FAIL doesn't respond")
Reported-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-05-19 20:05:07 -07:00
Mat Martineau d42f9e4e23 mptcp: Check for orphaned subflow before handling MP_FAIL timer
MP_FAIL timeout (waiting for a peer to respond to an MP_FAIL with
another MP_FAIL) is implemented using the MPTCP socket's sk_timer. That
timer is also used at MPTCP socket close, so it's important to not have
the two timer users interfere with each other.

At MPTCP socket close, all subflows are orphaned before sk_timer is
manipulated. By checking the SOCK_DEAD flag on the subflows, each
subflow can determine if the timer is safe to alter without acquiring
any MPTCP-level lock. This replaces code that was using the
mptcp_data_lock and MPTCP-level socket state checks that did not
correctly protect the timer.

Fixes: 49fa1919d6 ("mptcp: reset subflow when MP_FAIL doesn't respond")
Reviewed-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-05-19 20:05:07 -07:00
Paolo Abeni 7b16871f99 mptcp: stop using the mptcp_has_another_subflow() helper
The mentioned helper requires the msk socket lock, and the
current callers don't own it nor can't acquire it, so the
access is racy.

All the current callers are really checking for infinite mapping
fallback, and the latter condition is explicitly tracked by
the relevant msk variable: we can safely remove the caller usage
- and the caller itself.

The issue is present since MP_FAIL implementation, but the
fix only applies since the infinite fallback support, ence the
somewhat unexpected fixes tag.

Fixes: 0530020a7c ("mptcp: track and update contiguous data status")
Acked-and-tested-by: Geliang Tang <geliang.tang@suse.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-05-19 20:05:07 -07:00
Jakub Kicinski d7e6f58360 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
drivers/net/ethernet/mellanox/mlx5/core/main.c
  b33886971d ("net/mlx5: Initialize flow steering during driver probe")
  40379a0084 ("net/mlx5_fpga: Drop INNOVA TLS support")
  f2b41b32cd ("net/mlx5: Remove ipsec_ops function table")
https://lore.kernel.org/all/20220519040345.6yrjromcdistu7vh@sx1/
  16d42d3133 ("net/mlx5: Drain fw_reset when removing device")
  8324a02c34 ("net/mlx5: Add exit route when waiting for FW")
https://lore.kernel.org/all/20220519114119.060ce014@canb.auug.org.au/

tools/testing/selftests/net/mptcp/mptcp_join.sh
  e274f71540 ("selftests: mptcp: add subflow limits test-cases")
  b6e074e171 ("selftests: mptcp: add infinite map testcase")
  5ac1d2d634 ("selftests: mptcp: Add tests for userspace PM type")
https://lore.kernel.org/all/20220516111918.366d747f@canb.auug.org.au/

net/mptcp/options.c
  ba2c89e0ea ("mptcp: fix checksum byte order")
  1e39e5a32a ("mptcp: infinite mapping sending")
  ea66758c17 ("tcp: allow MPTCP to update the announced window")
https://lore.kernel.org/all/20220519115146.751c3a37@canb.auug.org.au/

net/mptcp/pm.c
  95d6865178 ("mptcp: fix subflow accounting on close")
  4d25247d3a ("mptcp: bypass in-kernel PM restrictions for non-kernel PMs")
https://lore.kernel.org/all/20220516111435.72f35dca@canb.auug.org.au/

net/mptcp/subflow.c
  ae66fb2ba6 ("mptcp: Do TCP fallback on early DSS checksum failure")
  0348c690ed ("mptcp: add the fallback check")
  f8d4bcacff ("mptcp: infinite mapping receiving")
https://lore.kernel.org/all/20220519115837.380bb8d4@canb.auug.org.au/

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-05-19 11:23:59 -07:00
Mat Martineau ae66fb2ba6 mptcp: Do TCP fallback on early DSS checksum failure
RFC 8684 section 3.7 describes several opportunities for a MPTCP
connection to "fall back" to regular TCP early in the connection
process, before it has been confirmed that MPTCP options can be
successfully propagated on all SYN, SYN/ACK, and data packets. If a peer
acknowledges the first received data packet with a regular TCP header
(no MPTCP options), fallback is allowed.

If the recipient of that first data packet finds a MPTCP DSS checksum
error, this provides an opportunity to fail gracefully with a TCP
fallback rather than resetting the connection (as might happen if a
checksum failure were detected later).

This commit modifies the checksum failure code to attempt fallback on
the initial subflow of a MPTCP connection, only if it's a failure in the
first data mapping. In cases where the peer initiates the connection,
requests checksums, is the first to send data, and the peer is sending
incorrect checksums (see
https://github.com/multipath-tcp/mptcp_net-next/issues/275), this allows
the connection to proceed as TCP rather than reset.

Fixes: dd8bcd1768 ("mptcp: validate the data checksum")
Acked-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>
2022-05-18 13:05:42 +01:00
Paolo Abeni ba2c89e0ea mptcp: fix checksum byte order
The MPTCP code typecasts the checksum value to u16 and
then converts it to big endian while storing the value into
the MPTCP option.

As a result, the wire encoding for little endian host is
wrong, and that causes interoperabilty interoperability
issues with other implementation or host with different endianness.

Address the issue writing in the packet the unmodified __sum16 value.

MPTCP checksum is disabled by default, interoperating with systems
with bad mptcp-level csum encoding should cause fallback to TCP.

Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/275
Fixes: c5b39e26d0 ("mptcp: send out checksum for DSS")
Fixes: 390b95a5fb ("mptcp: receive checksum for DSS")
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>
2022-05-18 13:05:42 +01:00
Florian Westphal ea1e301d04 mptcp: sockopt: add TCP_DEFER_ACCEPT support
Support this via passthrough to the underlying tcp listener socket.

Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/271
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-05-16 13:11:31 -07:00
Paolo Abeni 0ea5374255 Revert "mptcp: add data lock for sk timers"
This reverts commit 4293248c67.

Additional locks are not needed, all the touched sections
are already under mptcp socket lock protection.

Fixes: 4293248c67 ("mptcp: add data lock for sk timers")
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-05-16 13:11:31 -07:00
Paolo Abeni 95d6865178 mptcp: fix subflow accounting on close
If the PM closes a fully established MPJ subflow or the subflow
creation errors out in it's early stage the subflows counter is
not bumped accordingly.

This change adds the missing accounting, additionally taking care
of updating accordingly the 'accept_subflow' flag.

Fixes: a88c9e4969 ("mptcp: do not block subflows creation on errors")
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-05-13 17:04:30 -07:00
Martin KaFai Lau cae3873c5b net: inet: Retire port only listening_hash
The listen sk is currently stored in two hash tables,
listening_hash (hashed by port) and lhash2 (hashed by port and address).

After commit 0ee58dad5b ("net: tcp6: prefer listeners bound to an address")
and commit d9fbc7f643 ("net: tcp: prefer listeners bound to an address"),
the TCP-SYN lookup fast path does not use listening_hash.

The commit 05c0b35709 ("tcp: seq_file: Replace listening_hash with lhash2")
also moved the seq_file (/proc/net/tcp) iteration usage from
listening_hash to lhash2.

There are still a few listening_hash usages left.
One of them is inet_reuseport_add_sock() which uses the listening_hash
to search a listen sk during the listen() system call.  This turns
out to be very slow on use cases that listen on many different
VIPs at a popular port (e.g. 443).  [ On top of the slowness in
adding to the tail in the IPv6 case ].  The latter patch has a
selftest to demonstrate this case.

This patch takes this chance to move all remaining listening_hash
usages to lhash2 and then retire listening_hash.

Since most changes need to be done together, it is hard to cut
the listening_hash to lhash2 switch into small patches.  The
changes in this patch is highlighted here for the review
purpose.

1. Because of the listening_hash removal, lhash2 can use the
   sk->sk_nulls_node instead of the icsk->icsk_listen_portaddr_node.
   This will also keep the sk_unhashed() check to work as is
   after stop adding sk to listening_hash.

   The union is removed from inet_listen_hashbucket because
   only nulls_head is needed.

2. icsk->icsk_listen_portaddr_node and its helpers are removed.

3. The current lhash2 users needs to iterate with sk_nulls_node
   instead of icsk_listen_portaddr_node.

   One case is in the inet[6]_lhash2_lookup().

   Another case is the seq_file iterator in tcp_ipv4.c.
   One thing to note is sk_nulls_next() is needed
   because the old inet_lhash2_for_each_icsk_continue()
   does a "next" first before iterating.

4. Move the remaining listening_hash usage to lhash2

   inet_reuseport_add_sock() which this series is
   trying to improve.

   inet_diag.c and mptcp_diag.c are the final two
   remaining use cases and is moved to lhash2 now also.

Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-05-12 16:52:18 -07:00
Paolo Abeni 38acb6260f mptcp: add more offered MIBs counter
Track the exceptional handling of MPTCP-level offered window
with a few more counters for observability.

Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-05-05 19:00:16 -07:00
Paolo Abeni f3589be0c4 mptcp: never shrink offered window
As per RFC, the offered MPTCP-level window should never shrink.
While we currently track the right edge, we don't enforce the
above constraint on the wire.
Additionally, concurrent xmit on different subflows can end-up in
erroneous right edge update.
Address the above explicitly updating the announced window and
protecting the update with an additional atomic operation (sic)

Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-05-05 19:00:15 -07:00
Paolo Abeni ea66758c17 tcp: allow MPTCP to update the announced window
The MPTCP RFC requires that the MPTCP-level receive window's
right edge never moves backward. Currently the MPTCP code
enforces such constraint while tracking the right edge, but it
does not reflects it on the wire, as MPTCP lacks a suitable hook
to update accordingly the TCP header.

This change modifies the existing mptcp_write_options() hook,
providing the current packet's TCP header to the MPTCP protocol,
so that the next patch could implement the above mentioned
constraint.

No functional changes intended.

Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-05-05 19:00:15 -07:00
Paolo Abeni 92be2f5227 mptcp: add mib for xmit window sharing
Bump a counter for counter when snd_wnd is shared among subflow,
for observability's sake.

Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-05-05 19:00:15 -07:00
Paolo Abeni b713d00675 mptcp: really share subflow snd_wnd
As per RFC, mptcp subflows use a "shared" snd_wnd: the effective
window is the maximum among the current values received on all
subflows. Without such feature a data transfer using multiple
subflows could block.

Window sharing is currently implemented in the RX side:
__tcp_select_window uses the mptcp-level receive buffer to compute
the announced window.

That is not enough: the TCP stack will stick to the window size
received on the given subflow; we need to propagate the msk window
value on each subflow at xmit time.

Change the packet scheduler to ignore the subflow level window
and use instead the msk level one

Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-05-05 19:00:14 -07:00
Jakub Kicinski 16d083e28f net: switch to netif_napi_add_tx()
Switch net callers to the new API not requiring
the NAPI_POLL_WEIGHT argument.

Acked-by: Florian Fainelli <f.fainelli@gmail.com>
Reviewed-by: Alex Elder <elder@linaro.org>
Acked-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Acked-by: Alexandra Winter <wintera@linux.ibm.com>
Link: https://lore.kernel.org/r/20220504163725.550782-1-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-05-05 15:54:12 -07:00
Florian Westphal 702c2f646d mptcp: netlink: allow userspace-driven subflow establishment
This allows userspace to tell kernel to add a new subflow to an existing
mptcp connection.

Userspace provides the token to identify the mptcp-level connection
that needs a change in active subflows and the local and remote
addresses of the new or the to-be-removed subflow.

MPTCP_PM_CMD_SUBFLOW_CREATE requires the following parameters:
{ token, { loc_id, family, loc_addr4 | loc_addr6 }, { family, rem_addr4 |
rem_addr6, rem_port }

MPTCP_PM_CMD_SUBFLOW_DESTROY requires the following parameters:
{ token, { family, loc_addr4 | loc_addr6, loc_port }, { family, rem_addr4 |
rem_addr6, rem_port }

Acked-by: Paolo Abeni <pabeni@redhat.com>
Co-developed-by: Kishen Maloor <kishen.maloor@intel.com>
Signed-off-by: Kishen Maloor <kishen.maloor@intel.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-05-04 10:49:32 +01:00
Kishen Maloor d9a4594eda mptcp: netlink: Add MPTCP_PM_CMD_REMOVE
This change adds a MPTCP netlink command for issuing a
REMOVE_ADDR signal for an address over the chosen MPTCP
connection from a userspace path manager.

The command requires the following parameters: {token, loc_id}.

Acked-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Kishen Maloor <kishen.maloor@intel.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-05-04 10:49:31 +01:00
Kishen Maloor 9ab4807c84 mptcp: netlink: Add MPTCP_PM_CMD_ANNOUNCE
This change adds a MPTCP netlink interface for issuing
ADD_ADDR advertisements over the chosen MPTCP connection from a
userspace path manager.

The command requires the following parameters:
{ token, { loc_id, family, daddr4 | daddr6 [, dport] } [, if_idx],
flags[signal] }.

Acked-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Kishen Maloor <kishen.maloor@intel.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-05-04 10:49:31 +01:00
Florian Westphal 982f17ba1a mptcp: netlink: split mptcp_pm_parse_addr into two functions
Next patch will need to parse MPTCP_PM_ATTR_ADDR attributes and
fill an mptcp_addr_info structure from a different genl command
callback.

To avoid copy-paste, split the existing function to a helper
that does the common part and then call the helper from the
(renamed)mptcp_pm_parse_entry function.

Acked-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-05-04 10:49:31 +01:00
Kishen Maloor 8b20137012 mptcp: read attributes of addr entries managed by userspace PMs
This change introduces a parallel path in the kernel for retrieving
the local id, flags, if_index for an addr entry in the context of
an MPTCP connection that's being managed by a userspace PM. The
userspace and in-kernel PM modes deviate in their procedures for
obtaining this information.

Acked-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Kishen Maloor <kishen.maloor@intel.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-05-04 10:49:31 +01:00
Kishen Maloor 4638de5aef mptcp: handle local addrs announced by userspace PMs
This change adds an internal function to store/retrieve local
addrs announced by userspace PM implementations to/from its kernel
context. The function addresses the requirements of three scenarios:
1) ADD_ADDR announcements (which require that a local id be
provided), 2) retrieving the local id associated with an address,
and also where one may need to be assigned, and 3) reissuance of
ADD_ADDRs when there's a successful match of addr/id.

The list of all stored local addr entries is held under the
MPTCP sock structure. Memory for these entries is allocated from
the sock option buffer, so the list of addrs is bounded by optmem_max.
The list if not released via REMOVE_ADDR signals is ultimately
freed when the sock is destructed.

Acked-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Kishen Maloor <kishen.maloor@intel.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-05-04 10:49:31 +01:00
Kishen Maloor 304ab97f4c mptcp: allow ADD_ADDR reissuance by userspace PMs
This change allows userspace PM implementations to reissue ADD_ADDR
announcements (if necessary) based on their chosen policy.

Acked-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Kishen Maloor <kishen.maloor@intel.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-05-03 16:54:55 -07:00
Kishen Maloor 41b3c69bf9 mptcp: expose server_side attribute in MPTCP netlink events
This change records the 'server_side' attribute of MPTCP_EVENT_CREATED
and MPTCP_EVENT_ESTABLISHED events to inform their recipient about the
Client/Server role of the running MPTCP application.

Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/246
Acked-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Kishen Maloor <kishen.maloor@intel.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-05-03 16:54:55 -07:00
Kishen Maloor 70c708e826 mptcp: establish subflows from either end of connection
This change updates internal logic to permit subflows to be
established from either the client or server ends of MPTCP
connections. This symmetry and added flexibility may be
harnessed by PM implementations running on either end in
creating new subflows.

The essence of this change lies in not relying on the
"server_side" flag (which continues to be available if needed).

Acked-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Kishen Maloor <kishen.maloor@intel.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-05-03 16:54:55 -07:00
Kishen Maloor d1ace2d9ab mptcp: reflect remote port (not 0) in ANNOUNCED events
Per RFC 8684, if no port is specified in an ADD_ADDR message, MPTCP
SHOULD attempt to connect to the specified address on the same port
as the port that is already in use by the subflow on which the
ADD_ADDR signal was sent.

To facilitate that, this change reflects the specific remote port in
use by that subflow in MPTCP_EVENT_ANNOUNCED events.

Acked-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Kishen Maloor <kishen.maloor@intel.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-05-03 16:54:55 -07:00
Kishen Maloor 8a34839220 mptcp: store remote id from MP_JOIN SYN/ACK in local ctx
This change reads the addr id assigned to the remote endpoint
of a subflow from the MP_JOIN SYN/ACK message and stores it
in the related subflow context. The remote id was not being
captured prior to this change, and will now provide a consistent
view of remote endpoints and their ids as seen through netlink
events.

Acked-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Kishen Maloor <kishen.maloor@intel.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-05-03 16:54:54 -07:00
Kishen Maloor 4d25247d3a mptcp: bypass in-kernel PM restrictions for non-kernel PMs
Current limits on the # of addresses/subflows must apply only to
in-kernel PM managed sockets. Thus this change removes such
restrictions on connections overseen by non-kernel (e.g. userspace)
PMs. This change also ensures that the kernel does not record stats
inside struct mptcp_pm_data updated along kernel code paths when exercised
via non-kernel PMs.

Additionally, address announcements are acknolwedged and subflow
requests are honored only when it's deemed that	a userspace path
manager	is active at the time.

Acked-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Kishen Maloor <kishen.maloor@intel.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-05-03 16:54:54 -07:00
Mat Martineau 6bb63ccc25 mptcp: Add a per-namespace sysctl to set the default path manager type
The new net.mptcp.pm_type sysctl determines which path manager will be
used by each newly-created MPTCP socket.

v2: Handle builds without CONFIG_SYSCTL
v3: Clarify logic for type-specific PM init (Geliang Tang and Paolo Abeni)

Acked-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-04-29 17:25:14 -07:00
Mat Martineau 6961326e38 mptcp: Make kernel path manager check for userspace-managed sockets
Userspace-managed sockets should not have their subflows or
advertisements changed by the kernel path manager.

v3: Use helper function for PM mode (Paolo Abeni)

Acked-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-04-29 17:25:14 -07:00
Mat Martineau 14b06811be mptcp: Bypass kernel PM when userspace PM is enabled
When a MPTCP connection is managed by a userspace PM, bypass the kernel
PM for incoming advertisements and subflow events. Netlink events are
still sent to userspace.

v2: Remove unneeded check in mptcp_pm_rm_addr_received() (Kishen Maloor)
v3: Add and use helper function for PM mode (Paolo Abeni)

Acked-by: Paolo Abeni <pabeni@redhat.com>
Co-developed-by: Kishen Maloor <kishen.maloor@intel.com>
Signed-off-by: Kishen Maloor <kishen.maloor@intel.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-04-29 17:25:14 -07:00
Mat Martineau d85a8fde71 mptcp: Add a member to mptcp_pm_data to track kernel vs userspace mode
When adding support for netlink path management commands, the kernel
needs to know whether paths are being controlled by the in-kernel path
manager or a userspace PM.

Acked-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-04-29 17:25:13 -07:00
Mat Martineau 9273b9d579 mptcp: Remove redundant assignments in path manager init
A few members of the mptcp_pm_data struct were assigned to hard-coded
values in mptcp_pm_data_reset(), and then immediately changed in
mptcp_pm_nl_data_init().

Instead, flatten all the assignments in to mptcp_pm_data_reset().

v2: Resolve conflicts due to rename of mptcp_pm_data_reset()
v4: Resolve conflict in mptcp_pm_data_reset()

Acked-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-04-29 17:25:13 -07:00
Geliang Tang 49fa1919d6 mptcp: reset subflow when MP_FAIL doesn't respond
This patch adds a new msk->flags bit MPTCP_FAIL_NO_RESPONSE, then reuses
sk_timer to trigger a check if we have not received a response from the
peer after sending MP_FAIL. If the peer doesn't respond properly, reset
the subflow.

Signed-off-by: Geliang Tang <geliang.tang@suse.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-04-27 10:45:54 +01:00
Geliang Tang 9c81be0dbc mptcp: add MP_FAIL response support
This patch adds a new struct member mp_fail_response_expect in struct
mptcp_subflow_context to support MP_FAIL response. In the single subflow
with checksum error and contiguous data special case, a MP_FAIL is sent
in response to another MP_FAIL.

Signed-off-by: Geliang Tang <geliang.tang@suse.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-04-27 10:45:54 +01:00
Geliang Tang 4293248c67 mptcp: add data lock for sk timers
mptcp_data_lock() needs to be held when manipulating the msk
retransmit_timer or the sk sk_timer. This patch adds the data
lock for the both timers.

Signed-off-by: Geliang Tang <geliang.tang@suse.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-04-27 10:45:54 +01:00
Geliang Tang bcf3cf93f6 mptcp: use mptcp_stop_timer
Use the helper mptcp_stop_timer() instead of using sk_stop_timer() to
stop icsk_retransmit_timer directly.

Signed-off-by: Geliang Tang <geliang.tang@suse.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-04-27 10:45:53 +01:00
Geliang Tang 104125b82e mptcp: add mib for infinite map sending
This patch adds a new mib named MPTCP_MIB_INFINITEMAPTX, increase it
when a infinite mapping has been sent out.

Signed-off-by: Geliang Tang <geliang.tang@suse.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-04-23 11:51:05 +01:00
Geliang Tang f8d4bcacff mptcp: infinite mapping receiving
This patch adds the infinite mapping receiving logic. When the infinite
mapping is received, set the map_data_len of the subflow to 0.

In subflow_check_data_avail(), only reset the subflow when the map_data_len
of the subflow is non-zero.

Suggested-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Geliang Tang <geliang.tang@suse.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-04-23 11:51:05 +01:00
Geliang Tang 1e39e5a32a mptcp: infinite mapping sending
This patch adds the infinite mapping sending logic.

Add a new flag send_infinite_map in struct mptcp_subflow_context. Set
it true when a single contiguous subflow is in use and the
allow_infinite_fallback flag is true in mptcp_pm_mp_fail_received().

In mptcp_sendmsg_frag(), if this flag is true, call the new function
mptcp_update_infinite_map() to set the infinite mapping.

Add a new flag infinite_map in struct mptcp_ext, set it true in
mptcp_update_infinite_map(), and check this flag in a new helper
mptcp_check_infinite_map().

In mptcp_update_infinite_map(), set data_len to 0, and clear the
send_infinite_map flag, then do fallback.

In mptcp_established_options(), use the helper mptcp_check_infinite_map()
to let the infinite mapping DSS can be sent out in the fallback mode.

Suggested-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Geliang Tang <geliang.tang@suse.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-04-23 11:51:05 +01:00
Geliang Tang 0530020a7c mptcp: track and update contiguous data status
This patch adds a new member allow_infinite_fallback in mptcp_sock,
which is initialized to 'true' when the connection begins and is set
to 'false' on any retransmit or successful MP_JOIN. Only do infinite
mapping fallback if there is a single subflow AND there have been no
retransmissions AND there have never been any MP_JOINs.

Suggested-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Geliang Tang <geliang.tang@suse.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-04-23 11:51:05 +01:00
Geliang Tang 0348c690ed mptcp: add the fallback check
This patch adds the fallback check in subflow_check_data_avail(). Only
do the fallback when the msk hasn't fallen back yet.

Suggested-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Geliang Tang <geliang.tang@suse.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-04-23 11:51:05 +01:00
Geliang Tang 1761fed256 mptcp: don't send RST for single subflow
When a bad checksum is detected and a single subflow is in use, don't
send RST + MP_FAIL, send data_ack + MP_FAIL instead.

So invoke tcp_send_active_reset() only when mptcp_has_another_subflow()
is true.

Signed-off-by: Geliang Tang <geliang.tang@suse.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-04-23 11:51:05 +01:00
Oliver Hartkopp ec095263a9 net: remove noblock parameter from recvmsg() entities
The internal recvmsg() functions have two parameters 'flags' and 'noblock'
that were merged inside skb_recv_datagram(). As a follow up patch to commit
f4b41f062c ("net: remove noblock parameter from skb_recv_datagram()")
this patch removes the separate 'noblock' parameter for recvmsg().

Analogue to the referenced patch for skb_recv_datagram() the 'flags' and
'noblock' parameters are unnecessarily split up with e.g.

err = sk->sk_prot->recvmsg(sk, msg, size, flags & MSG_DONTWAIT,
                           flags & ~MSG_DONTWAIT, &addr_len);

or in

err = INDIRECT_CALL_2(sk->sk_prot->recvmsg, tcp_recvmsg, udp_recvmsg,
                      sk, msg, size, flags & MSG_DONTWAIT,
                      flags & ~MSG_DONTWAIT, &addr_len);

instead of simply using only flags all the time and check for MSG_DONTWAIT
where needed (to preserve for the formerly separated no(n)block condition).

Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Link: https://lore.kernel.org/r/20220411124955.154876-1-socketcan@hartkopp.net
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2022-04-12 15:00:25 +02:00
Florian Westphal 4fa39b701c mptcp: listen diag dump support
makes 'ss -Ml' show mptcp listen sockets.

Iterate over the tcp listen sockets and pick those that have mptcp ulp
info attached.

mptcp_diag_get_info() is modified to prefer msk->first for mptcp sockets
in listen state.  This reports accurate number for recv and send queue
(pending / max connection backlog counters).

Sample output:
ss -Mil
State        Recv-Q Send-Q Local Address:Port  Peer Address:Port
LISTEN       0      20     127.0.0.1:12000     0.0.0.0:*
         subflows_max:2

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-04-11 11:55:53 +01:00
Florian Westphal e8887b7161 mptcp: remove locking in mptcp_diag_fill_info
Problem is that listener iteration would call this from atomic context
so this locking is not allowed.

One way is to drop locks before calling the helper, but afaics the lock
isn't really needed, all values are fetched via READ_ONCE().

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-04-11 11:55:53 +01:00
Florian Westphal 6b9ea5c81e mptcp: diag: switch to context structure
Raw access to cb->arg[] is deprecated, use a context structure.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-04-11 11:55:53 +01:00
Geliang Tang c682bf536c mptcp: add pm_nl_pernet helpers
This patch adds two pm_nl_pernet related helpers, named pm_nl_get_pernet()
and pm_nl_get_pernet_from_msk() to get pm_nl_pernet from 'net' or 'msk'.
Use these helpers instead of using net_generic() directly.

Suggested-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Geliang Tang <geliang.tang@suse.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-04-11 11:55:53 +01:00
Paolo Abeni 0e203c3247 mptcp: reset the packet scheduler on PRIO change
Similar to the previous patch, for priority changes
requested by the local PM.

Reported-and-suggested-by: Davide Caratti <dcaratti@redhat.com>
Fixes: 067065422f ("mptcp: add the outgoing MP_PRIO support")
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>
2022-04-11 11:55:53 +01:00
Paolo Abeni 43f5b111d1 mptcp: reset the packet scheduler on incoming MP_PRIO
When an incoming MP_PRIO option changes the backup
status of any subflow, we need to reset the packet
scheduler status, or the next send could keep using
the previously selected subflow, without taking in account
the new priorities.

Reported-by: Davide Caratti <dcaratti@redhat.com>
Fixes: 40453a5c61 ("mptcp: add the incoming MP_PRIO support")
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>
2022-04-11 11:55:53 +01:00
Paolo Abeni 65a569b03c mptcp: optimize release_cb for the common case
The mptcp release callback checks several flags in atomic
context, but only MPTCP_CLEAN_UNA can be up frequently.

Reorganize the code to avoid multiple conditionals in the
most common scenarios.

Additional clarify a related comment.

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>
2022-04-11 11:55:53 +01:00
Jakub Kicinski 89695196f0 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Merge in overtime fixes, no conflicts.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-03-23 10:53:49 -07:00
Yonglong Li 12a18341b5 mptcp: send ADD_ADDR echo before create subflows
In some corner cases, the peer handing an incoming ADD_ADDR option, can
receive a retransmitted ADD_ADDR for the same address before the subflow
creation completes.

We can avoid the above issue by generating and sending the ADD_ADDR echo
before starting the MPJ subflow connection.

This slightly changes the behaviour of the packetdrill tests as the
ADD_ADDR echo packet is sent earlier.

Acked-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Yonglong Li <liyonglong@chinatelecom.cn>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Link: https://lore.kernel.org/r/20220317221444.426335-1-mathew.j.martineau@linux.intel.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-03-18 14:14:09 -07:00
Yonglong Li 3ef3905aa3 mptcp: Fix crash due to tcp_tsorted_anchor was initialized before release skb
Got crash when doing pressure test of mptcp:

===========================================================================
dst_release: dst:ffffa06ce6e5c058 refcnt:-1
kernel tried to execute NX-protected page - exploit attempt? (uid: 0)
BUG: unable to handle kernel paging request at ffffa06ce6e5c058
PGD 190a01067 P4D 190a01067 PUD 43fffb067 PMD 22e403063 PTE 8000000226e5c063
Oops: 0011 [#1] SMP PTI
CPU: 7 PID: 7823 Comm: kworker/7:0 Kdump: loaded Tainted: G            E
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.2.1 04/01/2014
Call Trace:
 ? skb_release_head_state+0x68/0x100
 ? skb_release_all+0xe/0x30
 ? kfree_skb+0x32/0xa0
 ? mptcp_sendmsg_frag+0x57e/0x750
 ? __mptcp_retrans+0x21b/0x3c0
 ? __switch_to_asm+0x35/0x70
 ? mptcp_worker+0x25e/0x320
 ? process_one_work+0x1a7/0x360
 ? worker_thread+0x30/0x390
 ? create_worker+0x1a0/0x1a0
 ? kthread+0x112/0x130
 ? kthread_flush_work_fn+0x10/0x10
 ? ret_from_fork+0x35/0x40
===========================================================================

In __mptcp_alloc_tx_skb skb was allocated and skb->tcp_tsorted_anchor will
be initialized, in under memory pressure situation sk_wmem_schedule will
return false and then kfree_skb. In this case skb->_skb_refdst is not null
because_skb_refdst and tcp_tsorted_anchor are stored in the same mem, and
kfree_skb will try to release dst and cause crash.

Fixes: f70cad1085 ("mptcp: stop relying on tcp_tx_skb_cache")
Reviewed-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Yonglong Li <liyonglong@chinatelecom.cn>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Link: https://lore.kernel.org/r/20220317220953.426024-1-mathew.j.martineau@linux.intel.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-03-18 14:13:48 -07:00
Geliang Tang 0dc626e5e8 mptcp: add fullmesh flag check for adding address
The fullmesh flag mustn't be used with the signal flag when adding an
address. This patch added the necessary flags check for this case.

Fixes: 73c762c1f0 ("mptcp: set fullmesh flag in pm_netlink")
Signed-off-by: Geliang Tang <geliang.tang@suse.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-03-08 22:06:12 -08:00
Paolo Abeni 4cf86ae84c mptcp: strict local address ID selection
The address ID selection for MPJ subflows created in response
to incoming ADD_ADDR option is currently unreliable: it happens
at MPJ socket creation time, when the local address could be
unknown.

Additionally, if the no local endpoint is available for the local
address, a new dummy endpoint is created, confusing the user-land.

This change refactor the code to move the address ID selection inside
the rebuild_header() helper, when the local address eventually
selected by the route lookup is finally known. If the address used
is not mapped by any endpoint - and thus can't be advertised/removed
pick the id 0 instead of allocate a new endpoint.

Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-03-08 22:06:12 -08:00
Paolo Abeni d045b9eb95 mptcp: introduce implicit endpoints
In some edge scenarios, an MPTCP subflows can use a local address
mapped by a "implicit" endpoint created by the in-kernel path manager.

Such endpoints presence can be confusing, as it's creation is hard
to track and will prevent the later endpoint creation from the user-space
using the same address.

Define a new endpoint flag to mark implicit endpoints and allow the
user-space to replace implicit them with user-provided data at endpoint
creation time.

Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-03-08 22:06:11 -08:00
Paolo Abeni 6fa0174a7c mptcp: more careful RM_ADDR generation
The in-kernel MPTCP path manager, when processing the MPTCP_PM_CMD_FLUSH_ADDR
command, generates RM_ADDR events for each known local address. While that
is allowed by the RFC, it makes unpredictable the exact number of RM_ADDR
generated when both ends flush the PM addresses.

This change restricts the RM_ADDR generation to previously explicitly
announced addresses, and adjust the expected results in a bunch of related
self-tests.

Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-03-08 22:06:11 -08:00
Geliang Tang ea56dcb43c mptcp: use MPTCP_SUBFLOW_NODATA
Set subflow->data_avail with the enum value MPTCP_SUBFLOW_NODATA, instead
of using 0 directly.

Reviewed-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Geliang Tang <geliang.tang@suse.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-03-08 22:06:11 -08:00
Geliang Tang 0eb4e7ee16 mptcp: add tracepoint in mptcp_sendmsg_frag
The tracepoint in get_mapping_status() only dumped the incoming mpext
fields. This patch added a new tracepoint in mptcp_sendmsg_frag() to dump
the outgoing mpext too.

Signed-off-by: Geliang Tang <geliang.tang@suse.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-03-08 22:06:10 -08:00
Geliang Tang e40dd439d6 mptcp: add the mibs for MP_RST
This patch added two more mibs for MP_RST, MPTCP_MIB_MPRSTTX for
the MP_RST sending and MPTCP_MIB_MPRSTRX for the MP_RST receiving.

Signed-off-by: Geliang Tang <geliang.tang@suse.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-03-04 21:54:30 -08:00
Geliang Tang 1e75629cb9 mptcp: add the mibs for MP_FASTCLOSE
This patch added two more mibs for MP_FASTCLOSE, MPTCP_MIB_MPFASTCLOSETX
for the MP_FASTCLOSE sending and MPTCP_MIB_MPFASTCLOSERX for receiving.

Also added a debug log for MP_FASTCLOSE receiving, printed out the recv_key
of MP_FASTCLOSE in mptcp_parse_option to show that MP_RST is received.

Signed-off-by: Geliang Tang <geliang.tang@suse.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-03-04 21:54:29 -08:00
Jakub Kicinski 80901bff81 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
net/batman-adv/hard-interface.c
  commit 690bb6fb64 ("batman-adv: Request iflink once in batadv-on-batadv check")
  commit 6ee3c393ee ("batman-adv: Demote batadv-on-batadv skip error message")
https://lore.kernel.org/all/20220302163049.101957-1-sw@simonwunderlich.de/

net/smc/af_smc.c
  commit 4d08b7b57e ("net/smc: Fix cleanup when register ULP fails")
  commit 462791bbfa ("net/smc: add sysctl interface for SMC")
https://lore.kernel.org/all/20220302112209.355def40@canb.auug.org.au/

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-03-03 11:55:12 -08:00
Mat Martineau 877d11f033 mptcp: Correctly set DATA_FIN timeout when number of retransmits is large
Syzkaller with UBSAN uncovered a scenario where a large number of
DATA_FIN retransmits caused a shift-out-of-bounds in the DATA_FIN
timeout calculation:

================================================================================
UBSAN: shift-out-of-bounds in net/mptcp/protocol.c:470:29
shift exponent 32 is too large for 32-bit type 'unsigned int'
CPU: 1 PID: 13059 Comm: kworker/1:0 Not tainted 5.17.0-rc2-00630-g5fbf21c90c60 #1
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.13.0-1ubuntu1.1 04/01/2014
Workqueue: events mptcp_worker
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106
 ubsan_epilogue+0xb/0x5a lib/ubsan.c:151
 __ubsan_handle_shift_out_of_bounds.cold+0xb2/0x20e lib/ubsan.c:330
 mptcp_set_datafin_timeout net/mptcp/protocol.c:470 [inline]
 __mptcp_retrans.cold+0x72/0x77 net/mptcp/protocol.c:2445
 mptcp_worker+0x58a/0xa70 net/mptcp/protocol.c:2528
 process_one_work+0x9df/0x16d0 kernel/workqueue.c:2307
 worker_thread+0x95/0xe10 kernel/workqueue.c:2454
 kthread+0x2f4/0x3b0 kernel/kthread.c:377
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>
================================================================================

This change limits the maximum timeout by limiting the size of the
shift, which keeps all intermediate values in-bounds.

Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/259
Fixes: 6477dd39e6 ("mptcp: Retransmit DATA_FIN")
Acked-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-02-24 21:54:54 -08:00
Paolo Abeni 07c2c7a3b6 mptcp: accurate SIOCOUTQ for fallback socket
The MPTCP SIOCOUTQ implementation is not very accurate in
case of fallback: it only measures the data in the MPTCP-level
write queue, but it does not take in account the subflow
write queue utilization. In case of fallback the first can be
empty, while the latter is not.

The above produces sporadic self-tests issues and can foul
legit user-space application.

Fix the issue additionally querying the subflow in case of fallback.

Fixes: 644807e3e4 ("mptcp: add SIOCINQ, OUTQ and OUTQNSD ioctls")
Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/260
Reported-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-02-24 21:54:53 -08:00
Jakub Kicinski aaa25a2fa7 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
tools/testing/selftests/net/mptcp/mptcp_join.sh
  34aa6e3bcc ("selftests: mptcp: add ip mptcp wrappers")

  857898eb4b ("selftests: mptcp: add missing join check")
  6ef84b1517 ("selftests: mptcp: more robust signal race test")
https://lore.kernel.org/all/20220221131842.468893-1-broonie@kernel.org/

drivers/net/ethernet/mellanox/mlx5/core/en/tc/act/act.h
drivers/net/ethernet/mellanox/mlx5/core/en/tc/act/ct.c
  fb7e76ea3f ("net/mlx5e: TC, Skip redundant ct clear actions")
  c63741b426 ("net/mlx5e: Fix MPLSoUDP encap to use MPLS action information")

  09bf979232 ("net/mlx5e: TC, Move pedit_headers_action to parse_attr")
  84ba8062e3 ("net/mlx5e: Test CT and SAMPLE on flow attr")
  efe6f961cd ("net/mlx5e: CT, Don't set flow flag CT for ct clear flow")
  3b49a7edec ("net/mlx5e: TC, Reject rules with multiple CT actions")

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-02-24 17:54:25 -08:00
Paolo Abeni f73c119463 mptcp: add mibs counter for ignored incoming options
The MPTCP in kernel path manager has some constraints on incoming
addresses announce processing, so that in edge scenarios it can
end-up dropping (ignoring) some of such announces.

The above is not very limiting in practice since such scenarios are
very uncommon and MPTCP will recover due to ADD_ADDR retransmissions.

This patch adds a few MIB counters to account for such drop events
to allow easier introspection of the critical scenarios.

Fixes: f7efc7771e ("mptcp: drop argument port from mptcp_pm_announce_addr")
Reviewed-by: Matthieu Baerts <matthieu.baerts@tessares.net>
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>
2022-02-19 12:28:00 +00:00
Paolo Abeni 837cf45df1 mptcp: fix race in incoming ADD_ADDR option processing
If an MPTCP endpoint received multiple consecutive incoming
ADD_ADDR options, mptcp_pm_add_addr_received() can overwrite
the current remote address value after the PM lock is released
in mptcp_pm_nl_add_addr_received() and before such address
is echoed.

Fix the issue caching the remote address value a little earlier
and always using the cached value after releasing the PM lock.

Fixes: f7efc7771e ("mptcp: drop argument port from mptcp_pm_announce_addr")
Reviewed-by: Matthieu Baerts <matthieu.baerts@tessares.net>
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>
2022-02-19 12:28:00 +00:00
Paolo Abeni 98247bc16a mptcp: fix race in overlapping signal events
After commit a88c9e4969 ("mptcp: do not block subflows
creation on errors"), if a signal address races with a failing
subflow creation, the subflow creation failure control path
can trigger the selection of the next address to be announced
while the current announced is still pending.

The above will cause the unintended suppression of the ADD_ADDR
announce.

Fix the issue skipping the to-be-suppressed announce before it
will mark an endpoint as already used. The relevant announce
will be triggered again when the current one will complete.

Fixes: a88c9e4969 ("mptcp: do not block subflows creation on errors")
Reviewed-by: Matthieu Baerts <matthieu.baerts@tessares.net>
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>
2022-02-19 12:28:00 +00:00
Florian Westphal 952382c648 mptcp: don't save tcp data_ready and write space callbacks
Assign the helpers directly rather than save/restore in the context
structure.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-02-16 20:52:06 -08:00
Florian Westphal 51fa7f8ebf mptcp: mark ops structures as ro_after_init
These structures are initialised from the init hooks, so we can't make
them 'const'.  But no writes occur afterwards, so we can use ro_after_init.

Also, remove bogus EXPORT_SYMBOL, the only access comes from ip
stack, not from kernel modules.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-02-16 20:52:05 -08:00
Paolo Abeni 90d9308821 mptcp: constify a bunch of of helpers
A few pm-related helpers don't touch arguments which lacking
the const modifier, let's constify them.

Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-02-16 20:52:05 -08:00
Geliang Tang af7939f390 mptcp: drop port parameter of mptcp_pm_add_addr_signal
Drop the port parameter of mptcp_pm_add_addr_signal() and reflect it to
avoid passing too many parameters.

Signed-off-by: Geliang Tang <geliang.tang@suse.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-02-16 20:52:05 -08:00
Geliang Tang 742e2f36c0 mptcp: drop unneeded type casts for hmac
Drop the unneeded type casts to 'unsigned long long' for printing out the
hmac values in add_addr_hmac_valid() and subflow_thmac_valid().

Signed-off-by: Geliang Tang <geliang.tang@suse.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-02-16 20:52:04 -08:00
Geliang Tang 0799e21b5a mptcp: drop unused sk in mptcp_get_options
The parameter 'sk' became useless since the code using it was dropped
from mptcp_get_options() in the commit 8d548ea1dd ("mptcp: do not set
unconditionally csum_reqd on incoming opt"). Let's drop it.

Signed-off-by: Geliang Tang <geliang.tang@suse.com>
Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-02-16 20:52:04 -08:00
Geliang Tang d6ab5ea2a3 mptcp: add SNDTIMEO setsockopt support
Add setsockopt support for SO_SNDTIMEO_OLD and SO_SNDTIMEO_NEW to fix this
error reported by the mptcp bpf selftest:

 (network_helpers.c:64: errno: Operation not supported) Failed to set SO_SNDTIMEO
 test_mptcp:FAIL:115

 All error logs:

 (network_helpers.c:64: errno: Operation not supported) Failed to set SO_SNDTIMEO
 test_mptcp:FAIL:115
 Summary: 0/0 PASSED, 0 SKIPPED, 1 FAILED

Signed-off-by: Geliang Tang <geliang.tang@suse.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-02-16 20:52:03 -08:00
Jakub Kicinski 5b91c5cc0e Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
No conflicts.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-02-10 17:29:56 -08:00
Kishen Maloor 029744cd4b mptcp: netlink: process IPv6 addrs in creating listening sockets
This change updates mptcp_pm_nl_create_listen_socket() to create
listening sockets bound to IPv6 addresses (where IPv6 is supported).

Fixes: 1729cf186d ("mptcp: create the listening socket for new port")
Acked-by: Geliang Tang <geliang.tang@suse.com>
Signed-off-by: Kishen Maloor <kishen.maloor@intel.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-02-09 21:44:35 -08:00
Geliang Tang 09f12c3ab7 mptcp: allow to use port and non-signal in set_flags
It's illegal to use both port and non-signal flags for adding address.
But it's legal to use both of them for setting flags, which always uses
non-signal flags, backup or fullmesh.

This patch moves this non-signal flag with port check from
mptcp_pm_parse_addr() to mptcp_nl_cmd_add_addr(). Do the check only when
adding addresses, not setting flags or deleting addresses.

Signed-off-by: Geliang Tang <geliang.tang@suse.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-02-04 20:30:23 -08:00
Geliang Tang 73c762c1f0 mptcp: set fullmesh flag in pm_netlink
This patch added the fullmesh flag setting support in pm_netlink.

If the fullmesh flag of the address is changed, remove all the related
subflows, update the fullmesh flag and create subflows again.

Acked-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Geliang Tang <geliang.tang@suse.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-02-03 11:44:08 +00:00
Geliang Tang 9ddd1cac6f mptcp: print out reset infos of MP_RST
This patch printed out the reset infos, reset_transient and reset_reason,
of MP_RST in mptcp_parse_option() to show that MP_RST is received.

Signed-off-by: Geliang Tang <geliang.tang@suse.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-02-03 11:44:08 +00:00
Matthieu Baerts 8cca39e251 mptcp: clarify when options can be used
RFC8684 doesn't seem to clearly specify which MPTCP options can be used
together.

Some options are mutually exclusive -- e.g. MP_CAPABLE and MP_JOIN --,
some can be used together -- e.g. DSS + MP_PRIO --, some can but we
prefer not to -- e.g. DSS + ADD_ADDR -- and some have to be used
together at some points -- e.g. MP_FAIL and DSS.

We need to clarify this as a base before allowing other modifications.

For example, does it make sense to send a RM_ADDR with an MPC or MPJ?
This remains open for possible future discussions.

Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-02-03 11:44:08 +00:00
Matthieu Baerts 902c8f8648 mptcp: reduce branching when writing MP_FAIL option
MP_FAIL should be use in very rare cases, either when the TCP RST flag
is set -- with or without an MP_RST -- or with a DSS, see
mptcp_established_options().

Here, we do the same in mptcp_write_options().

Co-developed-by: Geliang Tang <geliang.tang@suse.com>
Signed-off-by: Geliang Tang <geliang.tang@suse.com>
Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-02-03 11:44:08 +00:00
Geliang Tang d7889cfa0b mptcp: move the declarations of ssk and subflow
Move the declarations of ssk and subflow in MP_FAIL and MP_PRIO to the
beginning of the function mptcp_write_options().

Signed-off-by: Geliang Tang <geliang.tang@suse.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-02-03 11:44:08 +00:00
Kees Cook 63ec72bd58 mptcp: Use struct_group() to avoid cross-field memset()
In preparation for FORTIFY_SOURCE performing compile-time and run-time
field bounds checking for memcpy(), memmove(), and memset(), avoid
intentionally writing across neighboring fields.

Use struct_group() to capture the fields to be reset, so that memset()
can be appropriately bounds-checked by the compiler.

Cc: Matthieu Baerts <matthieu.baerts@tessares.net>
Cc: mptcp@lists.linux.dev
Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Link: https://lore.kernel.org/r/20220121073935.1154263-1-keescook@chromium.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-01-21 19:26:03 -08:00
Geliang Tang a4c0214fbe mptcp: fix removing ids bitmap setting
In mptcp_pm_nl_rm_addr_or_subflow(), the bit of rm_list->ids[i] in the
id_avail_bitmap should be set, not rm_list->ids[1]. This patch fixed it.

Fixes: 86e39e0448 ("mptcp: keep track of local endpoint still available for each msk")
Acked-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Geliang Tang <geliang.tang@suse.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-01-20 20:24:01 -08:00
Paolo Abeni 8e9eacad7e mptcp: fix msk traversal in mptcp_nl_cmd_set_flags()
The MPTCP endpoint list is under RCU protection, guarded by the
pernet spinlock. mptcp_nl_cmd_set_flags() traverses the list
without acquiring the spin-lock nor under the RCU critical section.

This change addresses the issue performing the lookup and the endpoint
update under the pernet spinlock.

Fixes: 0f9f696a50 ("mptcp: add set_flags command in PM netlink")
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-01-20 20:24:01 -08:00
Jakub Kicinski 8aaaf2f3af Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Merge in fixes directly in prep for the 5.17 merge window.
No conflicts.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-01-09 17:00:17 -08:00
Geliang Tang 8401e87f5a mptcp: reuse __mptcp_make_csum in validate_data_csum
This patch reused __mptcp_make_csum() in validate_data_csum() instead of
open-coding.

Signed-off-by: Geliang Tang <geliang.tang@suse.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-01-07 19:00:44 -08:00
Geliang Tang c312ee2191 mptcp: change the parameter of __mptcp_make_csum
This patch changed the type of the last parameter of __mptcp_make_csum()
from __sum16 to __wsum. And export this function in protocol.h.

Signed-off-by: Geliang Tang <geliang.tang@suse.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-01-07 19:00:44 -08:00
Mat Martineau 269bda9e7d mptcp: Check reclaim amount before reducing allocation
syzbot found a page counter underflow that was triggered by MPTCP's
reclaim code:

page_counter underflow: -4294964789 nr_pages=4294967295
WARNING: CPU: 2 PID: 3785 at mm/page_counter.c:56 page_counter_cancel+0xcf/0xe0 mm/page_counter.c:56
Modules linked in:
CPU: 2 PID: 3785 Comm: kworker/2:6 Not tainted 5.16.0-rc1-syzkaller #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.14.0-2 04/01/2014
Workqueue: events mptcp_worker

RIP: 0010:page_counter_cancel+0xcf/0xe0 mm/page_counter.c:56
Code: c7 04 24 00 00 00 00 45 31 f6 eb 97 e8 2a 2b b5 ff 4c 89 ea 48 89 ee 48 c7 c7 00 9e b8 89 c6 05 a0 c1 ba 0b 01 e8 95 e4 4b 07 <0f> 0b eb a8 4c 89 e7 e8 25 5a fb ff eb c7 0f 1f 00 41 56 41 55 49
RSP: 0018:ffffc90002d4f918 EFLAGS: 00010082

RAX: 0000000000000000 RBX: ffff88806a494120 RCX: 0000000000000000
RDX: ffff8880688c41c0 RSI: ffffffff815e8f28 RDI: fffff520005a9f15
RBP: ffffffff000009cb R08: 0000000000000000 R09: 0000000000000000
R10: ffffffff815e2cfe R11: 0000000000000000 R12: ffff88806a494120
R13: 00000000ffffffff R14: 0000000000000000 R15: 0000000000000001
FS:  0000000000000000(0000) GS:ffff88802cc00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b2de21000 CR3: 000000005ad59000 CR4: 0000000000150ee0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 page_counter_uncharge+0x2e/0x60 mm/page_counter.c:160
 drain_stock+0xc1/0x180 mm/memcontrol.c:2219
 refill_stock+0x139/0x2f0 mm/memcontrol.c:2271
 __sk_mem_reduce_allocated+0x24d/0x550 net/core/sock.c:2945
 __mptcp_rmem_reclaim net/mptcp/protocol.c:167 [inline]
 __mptcp_mem_reclaim_partial+0x124/0x410 net/mptcp/protocol.c:975
 mptcp_mem_reclaim_partial net/mptcp/protocol.c:982 [inline]
 mptcp_alloc_tx_skb net/mptcp/protocol.c:1212 [inline]
 mptcp_sendmsg_frag+0x18c6/0x2190 net/mptcp/protocol.c:1279
 __mptcp_push_pending+0x232/0x720 net/mptcp/protocol.c:1545
 mptcp_release_cb+0xfe/0x200 net/mptcp/protocol.c:2975
 release_sock+0xb4/0x1b0 net/core/sock.c:3306
 mptcp_worker+0x51e/0xc10 net/mptcp/protocol.c:2443
 process_one_work+0x9b2/0x1690 kernel/workqueue.c:2298
 worker_thread+0x658/0x11f0 kernel/workqueue.c:2445
 kthread+0x405/0x4f0 kernel/kthread.c:327
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>

__mptcp_mem_reclaim_partial() could call __mptcp_rmem_reclaim() with a
negative value, which passed that negative value to
__sk_mem_reduce_allocated() and triggered the splat above.

Check for a reclaim amount that is positive and large enough for
__mptcp_rmem_reclaim() to actually adjust rmem_fwd_alloc (much like
the sk_mem_reclaim_partial() code the function is based on).

v2: Use '>' instead of '>=', since SK_MEM_QUANTUM - 1 would get
right-shifted into nothing by __mptcp_rmem_reclaim.

Fixes: 6511882cdd ("mptcp: allocate fwd memory separately on the rx and tx path")
Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/252
Reported-and-tested-by: syzbot+bc9e2d2dbcb347dd215a@syzkaller.appspotmail.com
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Michal Hocko <mhocko@suse.com>
Acked-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>
2022-01-07 11:29:45 +00:00
Geliang Tang 110b6d1fe9 mptcp: fix a DSS option writing error
'ptr += 1;' was omitted in the original code.

If the DSS is the last option -- which is what we have most of the
time -- that's not an issue. But it is if we need to send something else
after like a RM_ADDR or an MP_PRIO.

Fixes: 1bff1e43a3 ("mptcp: optimize out option generation")
Reviewed-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Geliang Tang <geliang.tang@suse.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-01-07 11:29:45 +00:00
Matthieu Baerts 04fac2cae9 mptcp: fix opt size when sending DSS + MP_FAIL
When these two options had to be sent -- which is not common -- the DSS
size was not being taken into account in the remaining size.

Additionally in this situation, the reported size was only the one of
the MP_FAIL which can cause issue if at the end, we need to write more
in the TCP options than previously said.

Here we use a dedicated variable for MP_FAIL size to keep the
WARN_ON_ONCE() just after.

Fixes: c25aeb4e09 ("mptcp: MP_FAIL suboption sending")
Acked-and-tested-by: Geliang Tang <geliang.tang@suse.com>
Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-01-07 11:29:45 +00:00
Paolo Abeni e9d09baca6 mptcp: avoid atomic bit manipulation when possible
Currently the msk->flags bitmask carries both state for the
mptcp_release_cb() - mostly touched under the mptcp data lock
- and others state info touched even outside such lock scope.

As a consequence, msk->flags is always manipulated with
atomic operations.

This change splits such bitmask in two separate fields, so
that we use plain bit operations when touching the
cb-related info.

The MPTCP_PUSH_PENDING bit needs additional care, as it is the
only CB related field currently accessed either under the mptcp
data lock or the mptcp socket lock.
Let's add another mask just for such bit's sake.

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>
2022-01-07 11:27:07 +00:00
Paolo Abeni 3e5014909b mptcp: cleanup MPJ subflow list handling
We can simplify the join list handling leveraging the
mptcp_release_cb(): if we can acquire the msk socket
lock at mptcp_finish_join time, move the new subflow
directly into the conn_list, otherwise place it on join_list and
let the release_cb process such list.

Since pending MPJ connection are now always processed
in a timely way, we can avoid flushing the join list
every time we have to process all the current subflows.

Additionally we can now use the mptcp data lock to protect
the join_list, removing the additional spin lock.

Finally, the MPJ handshake is now always finalized under the
msk socket lock, we can drop the additional synchronization
between mptcp_finish_join() and mptcp_close().

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>
2022-01-07 11:27:07 +00:00
Paolo Abeni a88c9e4969 mptcp: do not block subflows creation on errors
If the MPTCP configuration allows for multiple subflows
creation, and the first additional subflows never reach
the fully established status - e.g. due to packets drop or
reset - the in kernel path manager do not move to the
next subflow.

This patch introduces a new PM helper to cope with MPJ
subflow creation failure and delay and hook it where appropriate.

Such helper triggers additional subflow creation, as needed
and updates the PM subflow counter, if the current one is
closing.

Additionally start all the needed additional subflows
as soon as the MPTCP socket is fully established, so we don't
have to cope with slow MPJ handshake blocking the next subflow
creation.

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>
2022-01-07 11:27:07 +00:00
Paolo Abeni 86e39e0448 mptcp: keep track of local endpoint still available for each msk
Include into the path manager status a bitmap tracking the list
of local endpoints still available - not yet used - for the
relevant mptcp socket.

Keep such map updated at endpoint creation/deletion time, so
that we can easily skip already used endpoint at local address
selection time.

The endpoint used by the initial subflow is lazyly accounted at
subflow creation time: the usage bitmap is be up2date before
endpoint selection and we avoid such unneeded task in some relevant
scenarios - e.g. busy servers accepting incoming subflows but
not creating any additional ones nor annuncing additional addresses.

Overall this allows for fair local endpoints usage in case of
subflow failure.

As a side effect, this patch also enforces that each endpoint
is used at most once for each mptcp connection.

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>
2022-01-07 11:27:07 +00:00
Paolo Abeni 71b077e483 mptcp: clean-up MPJ option writing
Check for all MPJ variant at once, this reduces the number
of conditionals traversed on average and will simplify the
next patch.

No functional change intended.

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>
2022-01-07 11:27:07 +00:00
Paolo Abeni f7d6a237d7 mptcp: fix per socket endpoint accounting
Since full-mesh endpoint support, the reception of a single ADD_ADDR
option can cause multiple subflows creation. When such option is
accepted we increment 'add_addr_accepted' by one. When we received
a paired RM_ADDR option, we deleted all the relevant subflows,
decrementing 'add_addr_accepted' by one for each of them.

We have a similar issue for 'local_addr_used'

Fix them moving the pm endpoint accounting outside the subflow
traversal.

Fixes: 1a0d6136c5 ("mptcp: local addresses fullmesh")
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>
2022-01-07 11:27:07 +00:00
Paolo Abeni 3d1d6d66e1 mptcp: implement support for user-space disconnect
Handle explicitly AF_UNSPEC in mptcp_stream_connnect() to
allow user-space to disconnect established MPTCP connections

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>
2022-01-07 11:27:07 +00:00
Paolo Abeni 71ba088ce0 mptcp: cleanup accept and poll
After the previous patch,  msk->subflow will never be deleted during
the whole msk lifetime. We don't need anymore to acquire references to
it in mptcp_stream_accept() and we can use the listener subflow accept
queue to simplify mptcp_poll() for listener socket.

Overall this removes a lock pair and 4 more atomic operations per
accept().

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>
2022-01-07 11:27:07 +00:00
Paolo Abeni b29fcfb54c mptcp: full disconnect implementation
The current mptcp_disconnect() implementation lacks several
steps, we additionally need to reset the msk socket state
and flush the subflow list.

Factor out the needed helper to avoid code duplication.

Additionally ensure that the initial subflow is disposed
only after mptcp_close(), just reset it at disconnect time.

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>
2022-01-07 11:27:06 +00:00
Paolo Abeni f284c0c773 mptcp: implement fastclose xmit path
Allow the MPTCP xmit path to add MP_FASTCLOSE suboption
on RST egress packets.

Additionally reorder related options writing to reduce
the number of conditionals required in the fast path.

Co-developed-by: Geliang Tang <geliang.tang@suse.com>
Signed-off-by: Geliang Tang <geliang.tang@suse.com>
Co-developed-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net>
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>
2022-01-07 11:27:06 +00:00
Paolo Abeni 58cd405b83 mptcp: keep snd_una updated for fallback socket
After shutdown, for fallback MPTCP sockets, we always have

write_seq == snd_una+1

The above will foul OUTQ ioctl(). Keep snd_una in sync with
write_seq even after shutdown.

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>
2022-01-07 11:27:06 +00:00
Jean Sacren 59060a47ca mptcp: clean up harmless false expressions
entry->addr.id is u8 with a range from 0 to 255 and MAX_ADDR_ID is 255.
We should drop both false expressions of (entry->addr.id > MAX_ADDR_ID).

We should also remove the obsolete parentheses in the first if branch.

Use U8_MAX for MAX_ADDR_ID and add a comment to show the link to
mptcp_addr_info.id as suggested by Mr. Matthieu Baerts.

Reviewed-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Jean Sacren <sakiwit@gmail.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-12-17 19:27:05 -08:00
Paolo Abeni 3ce0852c86 mptcp: enforce HoL-blocking estimation
The MPTCP packet scheduler has sub-optimal behavior with asymmetric
subflows: if the faster subflow-level cwin is closed, the packet
scheduler can enqueue "too much" data on a slower subflow.

When all the data on the faster subflow is acked, if the mptcp-level
cwin is closed, and link utilization becomes suboptimal.

The solution is implementing blest-like[1] HoL-blocking estimation,
transmitting only on the subflow with the shorter estimated time to
flush the queued memory. If such subflows cwin is closed, we wait
even if other subflows are available.

This is quite simpler than the original blest implementation, as we
leverage the pacing rate provided by the TCP socket. To get a more
accurate estimation for the subflow linger-time, we maintain a
per-subflow weighted average of such info.

Additionally drop magic numbers usage in favor of newly defined
macros and use more meaningful names for status variable.

[1] http://dl.ifip.org/db/conf/networking/networking2016/1570234725.pdf

Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/137
Reviewed-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-12-17 19:27:04 -08:00
Jakub Kicinski 7cd2802d74 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
No conflicts.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-12-16 16:13:19 -08:00
Maxim Galaganov 3d79e3756c mptcp: fix deadlock in __mptcp_push_pending()
__mptcp_push_pending() may call mptcp_flush_join_list() with subflow
socket lock held. If such call hits mptcp_sockopt_sync_all() then
subsequently __mptcp_sockopt_sync() could try to lock the subflow
socket for itself, causing a deadlock.

sysrq: Show Blocked State
task:ss-server       state:D stack:    0 pid:  938 ppid:     1 flags:0x00000000
Call Trace:
 <TASK>
 __schedule+0x2d6/0x10c0
 ? __mod_memcg_state+0x4d/0x70
 ? csum_partial+0xd/0x20
 ? _raw_spin_lock_irqsave+0x26/0x50
 schedule+0x4e/0xc0
 __lock_sock+0x69/0x90
 ? do_wait_intr_irq+0xa0/0xa0
 __lock_sock_fast+0x35/0x50
 mptcp_sockopt_sync_all+0x38/0xc0
 __mptcp_push_pending+0x105/0x200
 mptcp_sendmsg+0x466/0x490
 sock_sendmsg+0x57/0x60
 __sys_sendto+0xf0/0x160
 ? do_wait_intr_irq+0xa0/0xa0
 ? fpregs_restore_userregs+0x12/0xd0
 __x64_sys_sendto+0x20/0x30
 do_syscall_64+0x38/0x90
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7f9ba546c2d0
RSP: 002b:00007ffdc3b762d8 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00007f9ba56c8060 RCX: 00007f9ba546c2d0
RDX: 000000000000077a RSI: 0000000000e5e180 RDI: 0000000000000234
RBP: 0000000000cc57f0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f9ba56c8060
R13: 0000000000b6ba60 R14: 0000000000cc7840 R15: 41d8685b1d7901b8
 </TASK>

Fix the issue by using __mptcp_flush_join_list() instead of plain
mptcp_flush_join_list() inside __mptcp_push_pending(), as suggested by
Florian. The sockopt sync will be deferred to the workqueue.

Fixes: 1b3e7ede13 ("mptcp: setsockopt: handle SO_KEEPALIVE and SO_PRIORITY")
Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/244
Suggested-by: Florian Westphal <fw@strlen.de>
Reviewed-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Maxim Galaganov <max@internet.ru>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-12-14 18:49:40 -08:00
Florian Westphal d6692b3b97 mptcp: clear 'kern' flag from fallback sockets
The mptcp ULP extension relies on sk->sk_sock_kern being set correctly:
It prevents setsockopt(fd, IPPROTO_TCP, TCP_ULP, "mptcp", 6); from
working for plain tcp sockets (any userspace-exposed socket).

But in case of fallback, accept() can return a plain tcp sk.
In such case, sk is still tagged as 'kernel' and setsockopt will work.

This will crash the kernel, The subflow extension has a NULL ctx->conn
mptcp socket:

BUG: KASAN: null-ptr-deref in subflow_data_ready+0x181/0x2b0
Call Trace:
 tcp_data_ready+0xf8/0x370
 [..]

Fixes: cf7da0d66c ("mptcp: Create SUBFLOW socket for incoming connections")
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-12-14 18:49:39 -08:00
Florian Westphal 404cd9a221 mptcp: remove tcp ulp setsockopt support
TCP_ULP setsockopt cannot be used for mptcp because its already
used internally to plumb subflow (tcp) sockets to the mptcp layer.

syzbot managed to trigger a crash for mptcp connections that are
in fallback mode:

KASAN: null-ptr-deref in range [0x0000000000000020-0x0000000000000027]
CPU: 1 PID: 1083 Comm: syz-executor.3 Not tainted 5.16.0-rc2-syzkaller #0
RIP: 0010:tls_build_proto net/tls/tls_main.c:776 [inline]
[..]
 __tcp_set_ulp net/ipv4/tcp_ulp.c:139 [inline]
 tcp_set_ulp+0x428/0x4c0 net/ipv4/tcp_ulp.c:160
 do_tcp_setsockopt+0x455/0x37c0 net/ipv4/tcp.c:3391
 mptcp_setsockopt+0x1b47/0x2400 net/mptcp/sockopt.c:638

Remove support for TCP_ULP setsockopt.

Fixes: d9e4c12918 ("mptcp: only admit explicitly supported sockopt")
Reported-by: syzbot+1fd9b69cde42967d1add@syzkaller.appspotmail.com
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-12-14 18:49:39 -08:00
Eric Dumazet 1d2f3d3c62 mptcp: adjust to use netns refcount tracker
MPTCP can change sk_net_refcnt after sock_create_kern() call.

We need to change its corresponding get_net() to avoid
a splat at release time, as in :

refcount_t: decrement hit 0; leaking memory.
WARNING: CPU: 0 PID: 3599 at lib/refcount.c:31 refcount_warn_saturate+0xbf/0x1e0 lib/refcount.c:31
Modules linked in:
CPU: 1 PID: 3599 Comm: syz-fuzzer Not tainted 5.16.0-rc4-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:refcount_warn_saturate+0xbf/0x1e0 lib/refcount.c:31
Code: 1d b1 99 a1 09 31 ff 89 de e8 5d 3a 9c fd 84 db 75 e0 e8 74 36 9c fd 48 c7 c7 60 00 05 8a c6 05 91 99 a1 09 01 e8 cc 4b 27 05 <0f> 0b eb c4 e8 58 36 9c fd 0f b6 1d 80 99 a1 09 31 ff 89 de e8 28
RSP: 0018:ffffc90001f5fab0 EFLAGS: 00010286
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
RDX: ffff888021873a00 RSI: ffffffff815f1e28 RDI: fffff520003ebf48
RBP: 0000000000000004 R08: 0000000000000000 R09: 0000000000000000
R10: ffffffff815ebbce R11: 0000000000000000 R12: 1ffff920003ebf5b
R13: 00000000ffffffef R14: ffffffff8d2fcd94 R15: ffffc90001f5fd10
FS:  000000c00008a090(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f0a5b59e300 CR3: 000000001cbe6000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 __refcount_dec include/linux/refcount.h:344 [inline]
 refcount_dec include/linux/refcount.h:359 [inline]
 ref_tracker_free+0x4fe/0x610 lib/ref_tracker.c:101
 netns_tracker_free include/net/net_namespace.h:327 [inline]
 put_net_track include/net/net_namespace.h:341 [inline]
 __sk_destruct+0x4a6/0x920 net/core/sock.c:2042
 sk_destruct+0xbd/0xe0 net/core/sock.c:2058
 __sk_free+0xef/0x3d0 net/core/sock.c:2069
 sk_free+0x78/0xa0 net/core/sock.c:2080
 sock_put include/net/sock.h:1911 [inline]
 __mptcp_close_ssk+0x435/0x590 net/mptcp/protocol.c:2276
 __mptcp_destroy_sock+0x35f/0x830 net/mptcp/protocol.c:2702
 mptcp_close+0x5f8/0x7f0 net/mptcp/protocol.c:2750
 inet_release+0x12e/0x280 net/ipv4/af_inet.c:428
 inet6_release+0x4c/0x70 net/ipv6/af_inet6.c:476
 __sock_release+0xcd/0x280 net/socket.c:649
 sock_close+0x18/0x20 net/socket.c:1314
 __fput+0x286/0x9f0 fs/file_table.c:280
 task_work_run+0xdd/0x1a0 kernel/task_work.c:164
 tracehook_notify_resume include/linux/tracehook.h:189 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:175 [inline]
 exit_to_user_mode_prepare+0x27e/0x290 kernel/entry/common.c:207
 __syscall_exit_to_user_mode_work kernel/entry/common.c:289 [inline]
 syscall_exit_to_user_mode+0x19/0x60 kernel/entry/common.c:300
 do_syscall_64+0x42/0xb0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x44/0xae

Fixes: ffa84b5ffb ("net: add netns refcount tracker to struct sock")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Cc: Mat Martineau <mathew.j.martineau@linux.intel.com>
Cc: Florian Westphal <fw@strlen.de>
Acked-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Link: https://lore.kernel.org/r/20211214043208.3543046-1-eric.dumazet@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-12-14 18:45:50 -08:00
Paolo Abeni b0cdc5dbcf mptcp: never allow the PM to close a listener subflow
Currently, when deleting an endpoint the netlink PM treverses
all the local MPTCP sockets, regardless of their status.

If an MPTCP listener socket is bound to the IP matching the
delete endpoint, the listener TCP socket will be closed.
That is unexpected, the PM should only affect data subflows.

Additionally, syzbot was able to trigger a NULL ptr dereference
due to the above:

general protection fault, probably for non-canonical address 0xdffffc0000000003: 0000 [#1] PREEMPT SMP KASAN
KASAN: null-ptr-deref in range [0x0000000000000018-0x000000000000001f]
CPU: 1 PID: 6550 Comm: syz-executor122 Not tainted 5.16.0-rc4-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:__lock_acquire+0xd7d/0x54a0 kernel/locking/lockdep.c:4897
Code: 0f 0e 41 be 01 00 00 00 0f 86 c8 00 00 00 89 05 69 cc 0f 0e e9 bd 00 00 00 48 b8 00 00 00 00 00 fc ff df 48 89 da 48 c1 ea 03 <80> 3c 02 00 0f 85 f3 2f 00 00 48 81 3b 20 75 17 8f 0f 84 52 f3 ff
RSP: 0018:ffffc90001f2f818 EFLAGS: 00010016
RAX: dffffc0000000000 RBX: 0000000000000018 RCX: 0000000000000000
RDX: 0000000000000003 RSI: 0000000000000000 RDI: 0000000000000001
RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000001
R10: 0000000000000000 R11: 000000000000000a R12: 0000000000000000
R13: ffff88801b98d700 R14: 0000000000000000 R15: 0000000000000001
FS:  00007f177cd3d700(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f177cd1b268 CR3: 000000001dd55000 CR4: 0000000000350ee0
Call Trace:
 <TASK>
 lock_acquire kernel/locking/lockdep.c:5637 [inline]
 lock_acquire+0x1ab/0x510 kernel/locking/lockdep.c:5602
 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
 _raw_spin_lock_irqsave+0x39/0x50 kernel/locking/spinlock.c:162
 finish_wait+0xc0/0x270 kernel/sched/wait.c:400
 inet_csk_wait_for_connect net/ipv4/inet_connection_sock.c:464 [inline]
 inet_csk_accept+0x7de/0x9d0 net/ipv4/inet_connection_sock.c:497
 mptcp_accept+0xe5/0x500 net/mptcp/protocol.c:2865
 inet_accept+0xe4/0x7b0 net/ipv4/af_inet.c:739
 mptcp_stream_accept+0x2e7/0x10e0 net/mptcp/protocol.c:3345
 do_accept+0x382/0x510 net/socket.c:1773
 __sys_accept4_file+0x7e/0xe0 net/socket.c:1816
 __sys_accept4+0xb0/0x100 net/socket.c:1846
 __do_sys_accept net/socket.c:1864 [inline]
 __se_sys_accept net/socket.c:1861 [inline]
 __x64_sys_accept+0x71/0xb0 net/socket.c:1861
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7f177cd8b8e9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 b1 14 00 00 90 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 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f177cd3d308 EFLAGS: 00000246 ORIG_RAX: 000000000000002b
RAX: ffffffffffffffda RBX: 00007f177ce13408 RCX: 00007f177cd8b8e9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000003
RBP: 00007f177ce13400 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f177ce1340c
R13: 00007f177cde1004 R14: 6d705f706374706d R15: 0000000000022000
 </TASK>

Fix the issue explicitly skipping MPTCP socket in TCP_LISTEN
status.

Reported-and-tested-by: syzbot+e4d843bb96a9431e6331@syzkaller.appspotmail.com
Reviewed-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Fixes: 740d798e87 ("mptcp: remove id 0 address")
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Link: https://lore.kernel.org/r/ebc7594cdd420d241fb2172ddb8542ba64717657.1639238695.git.pabeni@redhat.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-12-13 18:12:58 -08:00
Maxim Galaganov 4f6e14bd19 mptcp: support TCP_CORK and TCP_NODELAY
First, add cork and nodelay fields to the mptcp_sock structure
so they can be used in sync_socket_options(), and fill them on setsockopt
while holding the msk socket lock.

Then, on setsockopt set proper tcp_sk(ssk)->nonagle values for subflows
by calling __tcp_sock_set_cork() or __tcp_sock_set_nodelay() on the ssk
while holding the ssk socket lock.

tcp_push_pending_frames() will be invoked on the ssk if a cork was cleared
or nodelay was set. Also set MPTCP_PUSH_PENDING bit by calling
mptcp_check_and_set_pending(). This will lead to __mptcp_push_pending()
being called inside mptcp_release_cb() with new tcp_sk(ssk)->nonagle.

Also add getsockopt support for TCP_CORK and TCP_NODELAY.

Acked-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Maxim Galaganov <max@internet.ru>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-12-07 11:36:31 -08:00
Maxim Galaganov 8b38217a2a mptcp: expose mptcp_check_and_set_pending
Expose the mptcp_check_and_set_pending() function for use inside MPTCP
sockopt code. The next patch will call it when TCP_CORK is cleared or
TCP_NODELAY is set on the MPTCP socket in order to push pending data
from mptcp_release_cb().

Acked-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Maxim Galaganov <max@internet.ru>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-12-07 11:36:31 -08:00
Florian Westphal 3b1e21eb60 mptcp: getsockopt: add support for IP_TOS
earlier patch added IP_TOS setsockopt support, this allows to get
the value set by earlier setsockopt.

Extends mptcp_put_int_option to handle u8 input/output by
adding required cast.

Reviewed-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-12-07 11:36:30 -08:00
Davide Caratti 602837e847 mptcp: allow changing the "backup" bit by endpoint id
a non-zero 'id' is sufficient to identify MPTCP endpoints: allow changing
the value of 'backup' bit by simply specifying the endpoint id.

Link: https://github.com/multipath-tcp/mptcp_net-next/issues/158
Signed-off-by: Davide Caratti <dcaratti@redhat.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-12-07 11:36:30 -08:00
Florian Westphal 644807e3e4 mptcp: add SIOCINQ, OUTQ and OUTQNSD ioctls
Allows to query in-sequence data ready for read(), total bytes in
write queue and total bytes in write queue that have not yet been sent.

v2: remove unneeded READ_ONCE() (Paolo Abeni)
v3: check for new data unconditionally in SIOCINQ ioctl (Mat Martineau)

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-12-07 11:36:29 -08:00
Florian Westphal 2c9e77659a mptcp: add TCP_INQ cmsg support
Support the TCP_INQ setsockopt.

This is a boolean that tells recvmsg path to include the remaining
in-sequence bytes in the cmsg data.

v2: do not use CB(skb)->offset, increment map_seq instead (Paolo Abeni)
v3: adjust CB(skb)->map_seq when taking skb from ofo queue (Paolo Abeni)

Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/224
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-12-07 11:36:29 -08:00
Jakub Kicinski 93d5404e89 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
drivers/net/ipa/ipa_main.c
  8afc7e471a ("net: ipa: separate disabling setup from modem stop")
  76b5fbcd6b ("net: ipa: kill ipa_modem_init()")

Duplicated include, drop one.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-11-26 13:45:19 -08:00
Paolo Abeni bcd9773431 mptcp: use delegate action to schedule 3rd ack retrans
Scheduling a delack in mptcp_established_options_mp() is
not a good idea: such function is called by tcp_send_ack() and
the pending delayed ack will be cleared shortly after by the
tcp_event_ack_sent() call in __tcp_transmit_skb().

Instead use the mptcp delegated action infrastructure to
schedule the delayed ack after the current bh processing completes.

Additionally moves the schedule_3rdack_retransmission() helper
into protocol.c to avoid making it visible in a different compilation
unit.

Fixes: ec3edaa7ca ("mptcp: Add handling of outgoing MP_JOIN requests")
Reviewed-by: Mat Martineau <mathew.j.martineau>@linux.intel.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-11-20 14:24:00 +00:00
Eric Dumazet ee50e67ba0 mptcp: fix delack timer
To compute the rtx timeout schedule_3rdack_retransmission() does multiple
things in the wrong way: srtt_us is measured in usec/8 and the timeout
itself is an absolute value.

Fixes: ec3edaa7ca ("mptcp: Add handling of outgoing MP_JOIN requests")
Acked-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Mat Martineau <mathew.j.martineau>@linux.intel.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-11-20 14:24:00 +00:00
Florian Westphal c9406a23c1 mptcp: sockopt: add SOL_IP freebind & transparent options
These options also need to be set before bind, so do the sync of msk to
new ssk socket a bit earlier.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-11-20 14:11:00 +00:00
Poorva Sonparote ffcacff87c mptcp: Support for IP_TOS for MPTCP setsockopt()
SOL_IP provides a way to configure network layer attributes in a
socket. This patch adds support for IP_TOS for setsockopt(.. ,SOL_IP, ..)

Support for SOL_IP is added in mptcp_setsockopt() and IP_TOS is handled in
a private function. The idea here is to take in the value passed for IP_TOS
and set it to the current subflow, open subflows as well new subflows that
might be created after the initial call to setsockopt(). This sync is done
using sync_socket_options(.., ssk) and setting the value of tos using
__ip_sock_set_tos(ssk,..).

The patch has been tested using the packetdrill script here -
https://github.com/multipath-tcp/mptcp_net-next/issues/220#issuecomment-947863717

Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/220
Signed-off-by: Poorva Sonparote <psonparo@redhat.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-11-20 14:11:00 +00:00
Eric Dumazet d477eb9004 net: make sock_inuse_add() available
MPTCP hard codes it, let us instead provide this helper.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-11-16 13:20:45 +00:00
Eric Dumazet 91b6d32563 net: cache align tcp_memory_allocated, tcp_sockets_allocated
tcp_memory_allocated and tcp_sockets_allocated often share
a common cache line, source of false sharing.

Also take care of udp_memory_allocated and mptcp_sockets_allocated.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-11-16 13:10:34 +00:00
Jakub Kicinski 7df621a3ee Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
include/net/sock.h
  7b50ecfcc6 ("net: Rename ->stream_memory_read to ->sock_is_readable")
  4c1e34c0db ("vsock: Enable y2038 safe timeval for timeout")

drivers/net/ethernet/marvell/octeontx2/af/rvu_debugfs.c
  0daa55d033 ("octeontx2-af: cn10k: debugfs for dumping LMTST map table")
  e77bcdd1f6 ("octeontx2-af: Display all enabled PF VF rsrc_alloc entries.")

Adjacent code addition in both cases, keep both.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-10-28 10:43:58 -07:00
Davide Caratti f7cc8890f3 mptcp: fix corrupt receiver key in MPC + data + checksum
using packetdrill it's possible to observe that the receiver key contains
random values when clients transmit MP_CAPABLE with data and checksum (as
specified in RFC8684 §3.1). Fix the layout of mptcp_out_options, to avoid
using the skb extension copy when writing the MP_CAPABLE sub-option.

Fixes: d7b2690837 ("mptcp: shrink mptcp_out_options struct")
Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/233
Reported-by: Poorva Sonparote <psonparo@redhat.com>
Signed-off-by: Davide Caratti <dcaratti@redhat.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Link: https://lore.kernel.org/r/20211027203855.264600-1-mathew.j.martineau@linux.intel.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-10-28 08:19:06 -07:00
Eric Dumazet a52fe46ef1 tcp: factorize ip_summed setting
Setting skb->ip_summed to CHECKSUM_PARTIAL can be centralized
in tcp_stream_alloc_skb() and __mptcp_do_alloc_tx_skb()
instead of being done multiple times.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-10-28 12:44:39 +01:00
Eric Dumazet f401da475f tcp: no longer set skb->reserved_tailroom
TCP/MPTCP sendmsg() no longer puts payload in skb->head,
we can remove not needed code.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-10-28 12:44:38 +01:00
Eric Dumazet 27728ba80f tcp: cleanup tcp_remove_empty_skb() use
All tcp_remove_empty_skb() callers now use tcp_write_queue_tail()
for the skb argument, we can therefore factorize code.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-10-28 12:44:38 +01:00
Geliang Tang b8e0def397 mptcp: drop unused sk in mptcp_push_release
Since mptcp_set_timeout() had removed from mptcp_push_release() in
commit 33d41c9cd7 ("mptcp: more accurate timeout"), the argument
sk in mptcp_push_release() became useless. Let's drop it.

Fixes: 33d41c9cd7 ("mptcp: more accurate timeout")
Reviewed-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Geliang Tang <geliang.tang@suse.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-10-27 18:20:30 -07:00
Paolo Abeni 6511882cdd mptcp: allocate fwd memory separately on the rx and tx path
All the mptcp receive path is protected by the msk socket
spinlock. As consequences, the tx path has to play a few tricks to
allocate the forward memory without acquiring the spinlock multiple
times, making the overall TX path quite complex.

This patch tries to clean-up a bit the tx path, using completely
separated fwd memory allocation, for the rx and the tx path.

The forward memory allocated in the rx path is now accounted in
msk->rmem_fwd_alloc and is (still) protected by the msk socket spinlock.

To cope with the above we provide a few MPTCP-specific variants for
the helpers to charge, uncharge, reclaim and free the forward memory
in the receive path.

msk->sk_forward_alloc now accounts only the forward memory for the tx
path, we can use the plain core sock helper to manipulate it and drop
quite a bit of complexity.

On memory pressure, both rx and tx fwd memories are reclaimed.

Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-10-27 18:20:29 -07:00
Mat Martineau 3828c51472 mptcp: Make mptcp_pm_nl_mp_prio_send_ack() static
This function is only used within pm_netlink.c now.

Fixes: 067065422f ("mptcp: add the outgoing MP_PRIO support")
Reviewed-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-10-16 08:46:08 +01:00
Paolo Abeni 72bcbc46a5 mptcp: increase default max additional subflows to 2
The current default does not allowing additional subflows, mostly
as a safety restriction to avoid uncontrolled resource consumption
on busy servers.

Still the system admin and/or the application have to opt-in to
MPTCP explicitly. After that, they need to change (increase) the
default maximum number of additional subflows.

Let set that to reasonable default, and make end-users life easier.

Additionally we need to update some self-tests accordingly.

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>
2021-10-16 08:46:08 +01:00
Tim Gardner 29211e7db2 mptcp: Avoid NULL dereference in mptcp_getsockopt_subflow_addrs()
Coverity complains of a possible NULL dereference in
mptcp_getsockopt_subflow_addrs():

 861       } else if (sk->sk_family == AF_INET6) {
    	3. returned_null: inet6_sk returns NULL. [show details]
    	4. var_assigned: Assigning: np = NULL return value from inet6_sk.
 862                const struct ipv6_pinfo *np = inet6_sk(sk);

Fix this by checking for NULL.

Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/231
Fixes: c11c5906bc ("mptcp: add MPTCP_SUBFLOW_ADDRS getsockopt support")
Cc: Florian Westphal <fw@strlen.de>
Signed-off-by: Tim Gardner <tim.gardner@canonical.com>
[mjm: Added WARN_ON_ONCE() to the unexpected case]
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-10-16 08:46:08 +01:00
Jakub Kicinski e15f5972b8 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
tools/testing/selftests/net/ioam6.sh
  7b1700e009 ("selftests: net: modify IOAM tests for undef bits")
  bf77b1400a ("selftests: net: Test for the IOAM encapsulation with IPv6")

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-10-14 16:50:14 -07:00
Paolo Abeni 612f71d732 mptcp: fix possible stall on recvmsg()
recvmsg() can enter an infinite loop if the caller provides the
MSG_WAITALL, the data present in the receive queue is not sufficient to
fulfill the request, and no more data is received by the peer.

When the above happens, mptcp_wait_data() will always return with
no wait, as the MPTCP_DATA_READY flag checked by such function is
set and never cleared in such code path.

Leveraging the above syzbot was able to trigger an RCU stall:

rcu: INFO: rcu_preempt self-detected stall on CPU
rcu:    0-...!: (10499 ticks this GP) idle=0af/1/0x4000000000000000 softirq=10678/10678 fqs=1
        (t=10500 jiffies g=13089 q=109)
rcu: rcu_preempt kthread starved for 10497 jiffies! g13089 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=1
rcu:    Unless rcu_preempt kthread gets sufficient CPU time, OOM is now expected behavior.
rcu: RCU grace-period kthread stack dump:
task:rcu_preempt     state:R  running task     stack:28696 pid:   14 ppid:     2 flags:0x00004000
Call Trace:
 context_switch kernel/sched/core.c:4955 [inline]
 __schedule+0x940/0x26f0 kernel/sched/core.c:6236
 schedule+0xd3/0x270 kernel/sched/core.c:6315
 schedule_timeout+0x14a/0x2a0 kernel/time/timer.c:1881
 rcu_gp_fqs_loop+0x186/0x810 kernel/rcu/tree.c:1955
 rcu_gp_kthread+0x1de/0x320 kernel/rcu/tree.c:2128
 kthread+0x405/0x4f0 kernel/kthread.c:327
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 8510 Comm: syz-executor827 Not tainted 5.15.0-rc2-next-20210920-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:bytes_is_nonzero mm/kasan/generic.c:84 [inline]
RIP: 0010:memory_is_nonzero mm/kasan/generic.c:102 [inline]
RIP: 0010:memory_is_poisoned_n mm/kasan/generic.c:128 [inline]
RIP: 0010:memory_is_poisoned mm/kasan/generic.c:159 [inline]
RIP: 0010:check_region_inline mm/kasan/generic.c:180 [inline]
RIP: 0010:kasan_check_range+0xc8/0x180 mm/kasan/generic.c:189
Code: 38 00 74 ed 48 8d 50 08 eb 09 48 83 c0 01 48 39 d0 74 7a 80 38 00 74 f2 48 89 c2 b8 01 00 00 00 48 85 d2 75 56 5b 5d 41 5c c3 <48> 85 d2 74 5e 48 01 ea eb 09 48 83 c0 01 48 39 d0 74 50 80 38 00
RSP: 0018:ffffc9000cd676c8 EFLAGS: 00000283
RAX: ffffed100e9a110e RBX: ffffed100e9a110f RCX: ffffffff88ea062a
RDX: 0000000000000001 RSI: 0000000000000008 RDI: ffff888074d08870
RBP: ffffed100e9a110e R08: 0000000000000001 R09: ffff888074d08877
R10: ffffed100e9a110e R11: 0000000000000000 R12: ffff888074d08000
R13: ffff888074d08000 R14: ffff888074d08088 R15: ffff888074d08000
FS:  0000555556d8e300(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000
S:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000020000180 CR3: 0000000068909000 CR4: 00000000001506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 instrument_atomic_read_write include/linux/instrumented.h:101 [inline]
 test_and_clear_bit include/asm-generic/bitops/instrumented-atomic.h:83 [inline]
 mptcp_release_cb+0x14a/0x210 net/mptcp/protocol.c:3016
 release_sock+0xb4/0x1b0 net/core/sock.c:3204
 mptcp_wait_data net/mptcp/protocol.c:1770 [inline]
 mptcp_recvmsg+0xfd1/0x27b0 net/mptcp/protocol.c:2080
 inet6_recvmsg+0x11b/0x5e0 net/ipv6/af_inet6.c:659
 sock_recvmsg_nosec net/socket.c:944 [inline]
 ____sys_recvmsg+0x527/0x600 net/socket.c:2626
 ___sys_recvmsg+0x127/0x200 net/socket.c:2670
 do_recvmmsg+0x24d/0x6d0 net/socket.c:2764
 __sys_recvmmsg net/socket.c:2843 [inline]
 __do_sys_recvmmsg net/socket.c:2866 [inline]
 __se_sys_recvmmsg net/socket.c:2859 [inline]
 __x64_sys_recvmmsg+0x20b/0x260 net/socket.c:2859
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7fc200d2dc39
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 41 15 00 00 90 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:00007ffc5758e5a8 EFLAGS: 00000246 ORIG_RAX: 000000000000012b
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00007fc200d2dc39
RDX: 0000000000000002 RSI: 00000000200017c0 RDI: 0000000000000003
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000f0b5ff
R10: 0000000000000100 R11: 0000000000000246 R12: 0000000000000003
R13: 00007ffc5758e5d0 R14: 00007ffc5758e5c0 R15: 0000000000000003

Fix the issue by replacing the MPTCP_DATA_READY bit with direct
inspection of the msk receive queue.

Reported-and-tested-by: syzbot+3360da629681aa0d22fe@syzkaller.appspotmail.com
Fixes: 7a6a6cbc3e ("mptcp: recvmsg() can drain data from multiple subflow")
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>
2021-10-08 14:55:54 +01:00
Jakub Kicinski dd9a887b35 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
drivers/net/phy/bcm7xxx.c
  d88fd1b546 ("net: phy: bcm7xxx: Fixed indirect MMD operations")
  f68d08c437 ("net: phy: bcm7xxx: Add EPHY entry for 72165")

net/sched/sch_api.c
  b193e15ac6 ("net: prevent user from passing illegal stab size")
  69508d4333 ("net_sched: Use struct_size() and flex_array_size() helpers")

Both cases trivial - adjacent code additions.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-09-30 14:49:21 -07:00
Eric Dumazet acbd0c8144 mptcp: use batch snmp operations in mptcp_seq_show()
Using snmp_get_cpu_field_batch() allows for better cpu cache
utilization, especially on hosts with large number of cpus.

Also remove special handling when mptcp mibs where not yet
allocated.

I chose to use temporary storage on the stack to keep this patch simple.
We might in the future use the storage allocated in netstat_seq_show().

Combined with prior patch (inlining snmp_get_cpu_field)
time to fetch and output mptcp counters on a 256 cpu host [1]
goes from 75 usec to 16 usec.

[1] L1 cache size is 32KB, it is not big enough to hold all dataset.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-09-30 14:17:10 +01:00
Paolo Abeni 4905455628 net: introduce and use lock_sock_fast_nested()
Syzkaller reported a false positive deadlock involving
the nl socket lock and the subflow socket lock:

MPTCP: kernel_bind error, err=-98
============================================
WARNING: possible recursive locking detected
5.15.0-rc1-syzkaller #0 Not tainted
--------------------------------------------
syz-executor998/6520 is trying to acquire lock:
ffff8880795718a0 (k-sk_lock-AF_INET){+.+.}-{0:0}, at: mptcp_close+0x267/0x7b0 net/mptcp/protocol.c:2738

but task is already holding lock:
ffff8880787c8c60 (k-sk_lock-AF_INET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1612 [inline]
ffff8880787c8c60 (k-sk_lock-AF_INET){+.+.}-{0:0}, at: mptcp_close+0x23/0x7b0 net/mptcp/protocol.c:2720

other info that might help us debug this:
 Possible unsafe locking scenario:

       CPU0
       ----
  lock(k-sk_lock-AF_INET);
  lock(k-sk_lock-AF_INET);

 *** DEADLOCK ***

 May be due to missing lock nesting notation

3 locks held by syz-executor998/6520:
 #0: ffffffff8d176c50 (cb_lock){++++}-{3:3}, at: genl_rcv+0x15/0x40 net/netlink/genetlink.c:802
 #1: ffffffff8d176d08 (genl_mutex){+.+.}-{3:3}, at: genl_lock net/netlink/genetlink.c:33 [inline]
 #1: ffffffff8d176d08 (genl_mutex){+.+.}-{3:3}, at: genl_rcv_msg+0x3e0/0x580 net/netlink/genetlink.c:790
 #2: ffff8880787c8c60 (k-sk_lock-AF_INET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1612 [inline]
 #2: ffff8880787c8c60 (k-sk_lock-AF_INET){+.+.}-{0:0}, at: mptcp_close+0x23/0x7b0 net/mptcp/protocol.c:2720

stack backtrace:
CPU: 1 PID: 6520 Comm: syz-executor998 Not tainted 5.15.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106
 print_deadlock_bug kernel/locking/lockdep.c:2944 [inline]
 check_deadlock kernel/locking/lockdep.c:2987 [inline]
 validate_chain kernel/locking/lockdep.c:3776 [inline]
 __lock_acquire.cold+0x149/0x3ab kernel/locking/lockdep.c:5015
 lock_acquire kernel/locking/lockdep.c:5625 [inline]
 lock_acquire+0x1ab/0x510 kernel/locking/lockdep.c:5590
 lock_sock_fast+0x36/0x100 net/core/sock.c:3229
 mptcp_close+0x267/0x7b0 net/mptcp/protocol.c:2738
 inet_release+0x12e/0x280 net/ipv4/af_inet.c:431
 __sock_release net/socket.c:649 [inline]
 sock_release+0x87/0x1b0 net/socket.c:677
 mptcp_pm_nl_create_listen_socket+0x238/0x2c0 net/mptcp/pm_netlink.c:900
 mptcp_nl_cmd_add_addr+0x359/0x930 net/mptcp/pm_netlink.c:1170
 genl_family_rcv_msg_doit+0x228/0x320 net/netlink/genetlink.c:731
 genl_family_rcv_msg net/netlink/genetlink.c:775 [inline]
 genl_rcv_msg+0x328/0x580 net/netlink/genetlink.c:792
 netlink_rcv_skb+0x153/0x420 net/netlink/af_netlink.c:2504
 genl_rcv+0x24/0x40 net/netlink/genetlink.c:803
 netlink_unicast_kernel net/netlink/af_netlink.c:1314 [inline]
 netlink_unicast+0x533/0x7d0 net/netlink/af_netlink.c:1340
 netlink_sendmsg+0x86d/0xdb0 net/netlink/af_netlink.c:1929
 sock_sendmsg_nosec net/socket.c:704 [inline]
 sock_sendmsg+0xcf/0x120 net/socket.c:724
 sock_no_sendpage+0x101/0x150 net/core/sock.c:2980
 kernel_sendpage.part.0+0x1a0/0x340 net/socket.c:3504
 kernel_sendpage net/socket.c:3501 [inline]
 sock_sendpage+0xe5/0x140 net/socket.c:1003
 pipe_to_sendpage+0x2ad/0x380 fs/splice.c:364
 splice_from_pipe_feed fs/splice.c:418 [inline]
 __splice_from_pipe+0x43e/0x8a0 fs/splice.c:562
 splice_from_pipe fs/splice.c:597 [inline]
 generic_splice_sendpage+0xd4/0x140 fs/splice.c:746
 do_splice_from fs/splice.c:767 [inline]
 direct_splice_actor+0x110/0x180 fs/splice.c:936
 splice_direct_to_actor+0x34b/0x8c0 fs/splice.c:891
 do_splice_direct+0x1b3/0x280 fs/splice.c:979
 do_sendfile+0xae9/0x1240 fs/read_write.c:1249
 __do_sys_sendfile64 fs/read_write.c:1314 [inline]
 __se_sys_sendfile64 fs/read_write.c:1300 [inline]
 __x64_sys_sendfile64+0x1cc/0x210 fs/read_write.c:1300
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7f215cb69969
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 14 00 00 90 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:00007ffc96bb3868 EFLAGS: 00000246 ORIG_RAX: 0000000000000028
RAX: ffffffffffffffda RBX: 00007f215cbad072 RCX: 00007f215cb69969
RDX: 0000000000000000 RSI: 0000000000000004 RDI: 0000000000000005
RBP: 0000000000000000 R08: 00007ffc96bb3a08 R09: 00007ffc96bb3a08
R10: 0000000100000002 R11: 0000000000000246 R12: 00007ffc96bb387c
R13: 431bde82d7b634db R14: 0000000000000000 R15: 0000000000000000

the problem originates from uncorrect lock annotation in the mptcp
code and is only visible since commit 2dcb96bacc ("net: core: Correct
the sock::sk_lock.owned lockdep annotations"), but is present since
the port-based endpoint support initial implementation.

This patch addresses the issue introducing a nested variant of
lock_sock_fast() and using it in the relevant code path.

Fixes: 1729cf186d ("mptcp: create the listening socket for new port")
Fixes: 2dcb96bacc ("net: core: Correct the sock::sk_lock.owned lockdep annotations")
Suggested-by: Thomas Gleixner <tglx@linutronix.de>
Reported-and-tested-by: syzbot+1dd53f7a89b299d59eaf@syzkaller.appspotmail.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-09-30 13:06:47 +01:00
Florian Westphal 3241a9c029 mptcp: re-arm retransmit timer if data is pending
The retransmit head will be NULL in case there is no in-flight data
(meaning all data injected into network has been acked).

In that case the retransmit timer is stopped.

This is only correct if there is no more pending, not-yet-sent data.

If there is, the retransmit timer needs to set the PENDING bit again so
that mptcp tries to send the remaining (new) data once a subflow can accept
more data.

Also, mptcp_subflow_get_retrans() has to be called unconditionally.

This function checks for subflows that have become unresponsive and marks
them as stale, so in the case where the rtx queue is empty, subflows
will never be marked stale which prevents available backup subflows from
becoming eligible for transmit.

Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/226
Acked-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-09-25 11:36:51 +01:00
Florian Westphal 9e65b6a5aa mptcp: remove tx_pending_data
The update on recovery is not correct.

msk->tx_pending_data += msk->snd_nxt - rtx_head->data_seq;

will update tx_pending_data multiple times when a subflow is declared
stale while earlier recovery is still in progress.
This means that tx_pending_data will still be positive even after
all data as has been transmitted.

Rather than fix it, remove this field: there are no consumers.
The outstanding data byte count can be computed either via

 "msk->write_seq - rtx_head->data_seq" or
 "msk->write_seq - msk->snd_una".

The latter is more recent/accurate estimate as rtx_head adjustment
is deferred until mptcp lock can be acquired.

Acked-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-09-25 11:36:51 +01:00
Paolo Abeni 765ff42552 mptcp: use lockdep_assert_held_once() instead of open-coding it
We have a few more places where the mptcp code duplicates
lockdep_assert_held_once(). Let's use the existing macro and
avoid a bunch of compiler's conditional.

Reviewed-by: Matthieu Baerts <matthieu.baerts@tessares.net>
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>
2021-09-25 11:36:51 +01:00
Geliang Tang 13ac17a32b mptcp: use OPTIONS_MPTCP_MPC
Since OPTIONS_MPTCP_MPC has been defined, use it instead of open-coding.

Acked-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Geliang Tang <geliangtang@xiaomi.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-09-25 11:36:51 +01:00
Florian Westphal 0d199e4363 mptcp: do not shrink snd_nxt when recovering
When recovering after a link failure, snd_nxt should not be set to a
lower value.  Else, update of snd_nxt is broken because:

  msk->snd_nxt += ret; (where ret is number of bytes sent)

assumes that snd_nxt always moves forward.
After reduction, its possible that snd_nxt update gets out of sync:
dfrag we just sent might have had a data sequence number even past
recovery_snd_nxt.

This change factors the common msk state update to a helper
and updates snd_nxt based on the current dfrag data sequence number.

The conditional is required for the recovery phase where we may
re-transmit old dfrags that are before current snd_nxt.

After this change, snd_nxt only moves forward and covers all in-sequence
data that was transmitted.

recovery_snd_nxt is retained to detect when recovery has completed.

Fixes: 1e1d9d6f11 ("mptcp: handle pending data on closed subflow")
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-09-25 11:36:51 +01:00
Davide Caratti 3f4a08909e mptcp: allow changing the 'backup' bit when no sockets are open
current Linux refuses to change the 'backup' bit of MPTCP endpoints, i.e.
using MPTCP_PM_CMD_SET_FLAGS, unless it finds (at least) one subflow that
matches the endpoint address. There is no reason for that, so we can just
ignore the return value of mptcp_nl_addr_backup(). In this way, endpoints
can reconfigure their 'backup' flag even if no MPTCP sockets are open (or
more generally, in case the MP_PRIO message is not sent out).

Fixes: 0f9f696a50 ("mptcp: add set_flags command in PM netlink")
Signed-off-by: Davide Caratti <dcaratti@redhat.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-09-24 10:51:36 +01:00
Florian Westphal ea1300b9df mptcp: don't return sockets in foreign netns
mptcp_token_get_sock() may return a mptcp socket that is in
a different net namespace than the socket that received the token value.

The mptcp syncookie code path had an explicit check for this,
this moves the test into mptcp_token_get_sock() function.

Eventually token.c should be converted to pernet storage, but
such change is not suitable for net tree.

Fixes: 2c5ebd001d ("mptcp: refactor token container")
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-09-24 10:51:36 +01:00
Paolo Abeni f70cad1085 mptcp: stop relying on tcp_tx_skb_cache
We want to revert the skb TX cache, but MPTCP is currently
using it unconditionally.

Rework the MPTCP tx code, so that tcp_tx_skb_cache is not
needed anymore: do the whole coalescing check, skb allocation
skb initialization/update inside mptcp_sendmsg_frag(), quite
alike the current TCP code.

Reviewed-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-09-23 12:50:26 +01:00
Paolo Abeni efe686ffce mptcp: ensure tx skbs always have the MPTCP ext
Due to signed/unsigned comparison, the expression:

	info->size_goal - skb->len > 0

evaluates to true when the size goal is smaller than the
skb size. That results in lack of tx cache refill, so that
the skb allocated by the core TCP code lacks the required
MPTCP skb extensions.

Due to the above, syzbot is able to trigger the following WARN_ON():

WARNING: CPU: 1 PID: 810 at net/mptcp/protocol.c:1366 mptcp_sendmsg_frag+0x1362/0x1bc0 net/mptcp/protocol.c:1366
Modules linked in:
CPU: 1 PID: 810 Comm: syz-executor.4 Not tainted 5.14.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:mptcp_sendmsg_frag+0x1362/0x1bc0 net/mptcp/protocol.c:1366
Code: ff 4c 8b 74 24 50 48 8b 5c 24 58 e9 0f fb ff ff e8 13 44 8b f8 4c 89 e7 45 31 ed e8 98 57 2e fe e9 81 f4 ff ff e8 fe 43 8b f8 <0f> 0b 41 bd ea ff ff ff e9 6f f4 ff ff 4c 89 e7 e8 b9 8e d2 f8 e9
RSP: 0018:ffffc9000531f6a0 EFLAGS: 00010216
RAX: 000000000000697f RBX: 0000000000000000 RCX: ffffc90012107000
RDX: 0000000000040000 RSI: ffffffff88eac9e2 RDI: 0000000000000003
RBP: ffff888078b15780 R08: 0000000000000000 R09: 0000000000000000
R10: ffffffff88eac017 R11: 0000000000000000 R12: ffff88801de0a280
R13: 0000000000006b58 R14: ffff888066278280 R15: ffff88803c2fe9c0
FS:  00007fd9f866e700(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007faebcb2f718 CR3: 00000000267cb000 CR4: 00000000001506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 __mptcp_push_pending+0x1fb/0x6b0 net/mptcp/protocol.c:1547
 mptcp_release_cb+0xfe/0x210 net/mptcp/protocol.c:3003
 release_sock+0xb4/0x1b0 net/core/sock.c:3206
 sk_stream_wait_memory+0x604/0xed0 net/core/stream.c:145
 mptcp_sendmsg+0xc39/0x1bc0 net/mptcp/protocol.c:1749
 inet6_sendmsg+0x99/0xe0 net/ipv6/af_inet6.c:643
 sock_sendmsg_nosec net/socket.c:704 [inline]
 sock_sendmsg+0xcf/0x120 net/socket.c:724
 sock_write_iter+0x2a0/0x3e0 net/socket.c:1057
 call_write_iter include/linux/fs.h:2163 [inline]
 new_sync_write+0x40b/0x640 fs/read_write.c:507
 vfs_write+0x7cf/0xae0 fs/read_write.c:594
 ksys_write+0x1ee/0x250 fs/read_write.c:647
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x4665f9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 bc ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fd9f866e188 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 000000000056c038 RCX: 00000000004665f9
RDX: 00000000000e7b78 RSI: 0000000020000000 RDI: 0000000000000003
RBP: 00000000004bfcc4 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056c038
R13: 0000000000a9fb1f R14: 00007fd9f866e300 R15: 0000000000022000

Fix the issue rewriting the relevant expression to avoid
sign-related problems - note: size_goal is always >= 0.

Additionally, ensure that the skb in the tx cache always carries
the relevant extension.

Reported-and-tested-by: syzbot+263a248eec3e875baa7b@syzkaller.appspotmail.com
Fixes: 1094c6fe72 ("mptcp: fix possible divide by zero")
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-09-23 12:50:22 +01:00
Paolo Abeni 977d293e23 mptcp: ensure tx skbs always have the MPTCP ext
Due to signed/unsigned comparison, the expression:

	info->size_goal - skb->len > 0

evaluates to true when the size goal is smaller than the
skb size. That results in lack of tx cache refill, so that
the skb allocated by the core TCP code lacks the required
MPTCP skb extensions.

Due to the above, syzbot is able to trigger the following WARN_ON():

WARNING: CPU: 1 PID: 810 at net/mptcp/protocol.c:1366 mptcp_sendmsg_frag+0x1362/0x1bc0 net/mptcp/protocol.c:1366
Modules linked in:
CPU: 1 PID: 810 Comm: syz-executor.4 Not tainted 5.14.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:mptcp_sendmsg_frag+0x1362/0x1bc0 net/mptcp/protocol.c:1366
Code: ff 4c 8b 74 24 50 48 8b 5c 24 58 e9 0f fb ff ff e8 13 44 8b f8 4c 89 e7 45 31 ed e8 98 57 2e fe e9 81 f4 ff ff e8 fe 43 8b f8 <0f> 0b 41 bd ea ff ff ff e9 6f f4 ff ff 4c 89 e7 e8 b9 8e d2 f8 e9
RSP: 0018:ffffc9000531f6a0 EFLAGS: 00010216
RAX: 000000000000697f RBX: 0000000000000000 RCX: ffffc90012107000
RDX: 0000000000040000 RSI: ffffffff88eac9e2 RDI: 0000000000000003
RBP: ffff888078b15780 R08: 0000000000000000 R09: 0000000000000000
R10: ffffffff88eac017 R11: 0000000000000000 R12: ffff88801de0a280
R13: 0000000000006b58 R14: ffff888066278280 R15: ffff88803c2fe9c0
FS:  00007fd9f866e700(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007faebcb2f718 CR3: 00000000267cb000 CR4: 00000000001506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 __mptcp_push_pending+0x1fb/0x6b0 net/mptcp/protocol.c:1547
 mptcp_release_cb+0xfe/0x210 net/mptcp/protocol.c:3003
 release_sock+0xb4/0x1b0 net/core/sock.c:3206
 sk_stream_wait_memory+0x604/0xed0 net/core/stream.c:145
 mptcp_sendmsg+0xc39/0x1bc0 net/mptcp/protocol.c:1749
 inet6_sendmsg+0x99/0xe0 net/ipv6/af_inet6.c:643
 sock_sendmsg_nosec net/socket.c:704 [inline]
 sock_sendmsg+0xcf/0x120 net/socket.c:724
 sock_write_iter+0x2a0/0x3e0 net/socket.c:1057
 call_write_iter include/linux/fs.h:2163 [inline]
 new_sync_write+0x40b/0x640 fs/read_write.c:507
 vfs_write+0x7cf/0xae0 fs/read_write.c:594
 ksys_write+0x1ee/0x250 fs/read_write.c:647
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x4665f9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 bc ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fd9f866e188 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 000000000056c038 RCX: 00000000004665f9
RDX: 00000000000e7b78 RSI: 0000000020000000 RDI: 0000000000000003
RBP: 00000000004bfcc4 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056c038
R13: 0000000000a9fb1f R14: 00007fd9f866e300 R15: 0000000000022000

Fix the issue rewriting the relevant expression to avoid
sign-related problems - note: size_goal is always >= 0.

Additionally, ensure that the skb in the tx cache always carries
the relevant extension.

Reported-and-tested-by: syzbot+263a248eec3e875baa7b@syzkaller.appspotmail.com
Fixes: 1094c6fe72 ("mptcp: fix possible divide by zero")
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-09-22 14:39:41 +01:00
Florian Westphal c11c5906bc mptcp: add MPTCP_SUBFLOW_ADDRS getsockopt support
This retrieves the address pairs of all subflows currently
active for a given mptcp connection.

It re-uses the same meta-header as for MPTCP_TCPINFO.

A new structure is provided to hold the subflow
address data:

struct mptcp_subflow_addrs {
	union {
		__kernel_sa_family_t sa_family;
		struct sockaddr sa_local;
		struct sockaddr_in sin_local;
		struct sockaddr_in6 sin6_local;
		struct sockaddr_storage ss_local;
	};
	union {
		struct sockaddr sa_remote;
		struct sockaddr_in sin_remote;
		struct sockaddr_in6 sin6_remote;
		struct sockaddr_storage ss_remote;
	};
};

Usage of the new getsockopt is very similar to
MPTCP_TCPINFO one.

Userspace allocates a
'struct mptcp_subflow_data', followed by one or
more 'struct mptcp_subflow_addrs', then inits the
mptcp_subflow_data structure as follows:

struct mptcp_subflow_addrs *sf_addr;
struct mptcp_subflow_data *addr;
socklen_t olen = sizeof(*addr) + (8 * sizeof(*sf_addr));

addr = malloc(olen);
addr->size_subflow_data = sizeof(*addr);
addr->num_subflows = 0;
addr->size_kernel = 0;
addr->size_user = sizeof(struct mptcp_subflow_addrs);

sf_addr = (struct mptcp_subflow_addrs *)(addr + 1);

and then retrieves the endpoint addresses via:
ret = getsockopt(fd, SOL_MPTCP, MPTCP_SUBFLOW_ADDRS,
		 addr, &olen);

If the call succeeds, kernel will have added up to 8
endpoint addresses after the 'mptcp_subflow_data' header.

Userspace needs to re-check 'olen' value to detect how
many bytes have been filled in by the kernel.

Userspace can check addr->num_subflows to discover when
there were more subflows that available data space.

Co-developed-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-09-18 14:20:01 +01:00
Florian Westphal 06f15cee36 mptcp: add MPTCP_TCPINFO getsockopt support
Allow users to retrieve TCP_INFO data of all subflows.

Users need to pre-initialize a meta header that has to be
prepended to the data buffer that will be filled with the tcp info data.

The meta header looks like this:

struct mptcp_subflow_data {
 __u32 size_subflow_data;/* size of this structure in userspace */
 __u32 num_subflows;	/* must be 0, set by kernel */
 __u32 size_kernel;	/* must be 0, set by kernel */
 __u32 size_user;	/* size of one element in data[] */
} __attribute__((aligned(8)));

size_subflow_data has to be set to 'sizeof(struct mptcp_subflow_data)'.
This allows to extend mptcp_subflow_data structure later on without
breaking backwards compatibility.

If the structure is extended later on, kernel knows where the
userspace-provided meta header ends, even if userspace uses an older
(smaller) version of the structure.

num_subflows must be set to 0. If the getsockopt request succeeds (return
value is 0), it will be updated to contain the number of active subflows
for the given logical connection.

size_kernel must be set to 0. If the getsockopt request is successful,
it will contain the size of the 'struct tcp_info' as known by the kernel.
This is informational only.

size_user must be set to 'sizeof(struct tcp_info)'.

This allows the kernel to only fill in the space reserved/expected by
userspace.

Example:

struct my_tcp_info {
  struct mptcp_subflow_data d;
  struct tcp_info ti[2];
};
struct my_tcp_info ti;
socklen_t olen;

memset(&ti, 0, sizeof(ti));

ti.d.size_subflow_data = sizeof(struct mptcp_subflow_data);
ti.d.size_user = sizeof(struct tcp_info);
olen = sizeof(ti);

ret = getsockopt(fd, SOL_MPTCP, MPTCP_TCPINFO, &ti, &olen);
if (ret < 0)
	die_perror("getsockopt MPTCP_TCPINFO");

mptcp_subflow_data.num_subflows is populated with the number of
subflows that exist on the kernel side for the logical mptcp connection.

This allows userspace to re-try with a larger tcp_info array if the number
of subflows was larger than the available space in the ti[] array.

olen has to be set to the number of bytes that userspace has allocated to
receive the kernel data.  It will be updated to contain the real number
bytes that have been copied to by the kernel.

In the above example, if the number if subflows was 1, olen is equal to
'sizeof(struct mptcp_subflow_data) + sizeof(struct tcp_info).
For 2 or more subflows olen is equal to 'sizeof(struct my_tcp_info)'.

If there was more data that could not be copied due to lack of space
in the option buffer, userspace can detect this by checking
mptcp_subflow_data->num_subflows.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-09-18 14:20:01 +01:00