[PATCH v8 0/7] Fix sock_send reordering issue (#52401)

[Jinoh Kang]

This fixes the send part of the issue #52401 [1]: "Improper
synchronization in sock_recv/sock_send leads to arbitrary reordering of
completion of I/O requests", which was initially reported (outside
Bugzilla) by Dongwan Kim [2].

Changelog:
v1 -> v2:
- drop patch "server: Compact struct set_async_direct_result_reply."
- add async and fd arguments to async_initial_status_callback
- recv_socket_initial_callback: pass OOB flag via private instead of
  implementing two separate functions for OOB and non-OOB
- detect short write in send_socket_initial_callback
- preserve the behaviour of returning success if we had a short write
  and the socket is nonblocking and force_async is unset
v2 -> v3:
- fix typo in comment
v3 -> v4:
- fix typo in commit message
- address feedback
- drop patch "server: Defer postprocessing until after setting initial
  status in recv_socket handler."
v4 -> v5:
- drop patch "server: Add async_initial_status_callback."
- drop patch "server: Defer postprocessing until after setting initial
  status in send_socket handler."
- add patch "server: Ensure completion_callback is called before async
  is destroyed."
- add patch "ws2_32/tests: Continue sending remaining data on short
  write in test_write_events."
- add patch "server: Defer clearing events until async is either pending
  or completed in send_socket handler."
- add patch "server: Ensure datagram sockets are bound in send_socket."
v5 -> v6:
- centralise status code computation in one place, even for bind errno
  translation
- fix erroneous subject (s/either pending or completed/completed/)
v6 -> v7:
- drop patch "server: Ensure completion_callback is called before async
  is destroyed."
- add patch "server: Ensure async completion callback is called on
  synchronous failure."
- add patch "server: Allow async completion callback to retrieve status
  on synchronous failure."
v7 -> v8:
- drop committed patches
- edit commit message of "server: Ensure completion_callback is called
  before async is destroyed." as per feedback (thanks zf)
- move a sock_reselect() into the prior if block (thanks zf)

Supersedes 227636 - 227644.
Supersedes 228988 - 228998.
Supersedes 230282 - 230293 (sans already committed patches).

[1] https://bugs.winehq.org/show_bug.cgi?id=52401
[2] https://www.winehq.org/pipermail/wine-devel/2021-May/186454.html

Jinoh Kang (7):
  server: Generalise async completion callback to be called on
    synchronous failure.
  server: Allow async completion callback to retrieve status on
    synchronous failure.
  server: Defer clearing events until async is completed in send_socket
    handler.
  server: Attempt to complete I/O request immediately in send_socket.
  server: Ensure datagram sockets are bound in send_socket.
  ntdll: Don't call try_send before server call in sock_send.
  server: Replace redundant send_socket status fields with force_async
    boolean field.

 dlls/ntdll/unix/socket.c |  89 +++++++++++++++-------
 dlls/ws2_32/tests/sock.c |  14 ++--
 server/async.c           |  14 +++-
 server/protocol.def      |   4 +-
 server/sock.c            | 161 +++++++++++++++++++++++++++------------
 5 files changed, 195 insertions(+), 87 deletions(-)

-- 
2.34.1