[PATCH mptcp-next v2 00/10] selftests: cover more MPTCP socket options

[Geliang Tang <geliang@kernel.org>]

From: Geliang Tang <tanggeliang@kylinos.cn>

v2:
 - IP_FREEBIND/IPV6_FREEBIND are set in do_getsockopt_transparent, fix
   it.
 - Use "for" loops in mptcp_sockopt.sh.
 - Move "add IP_TOS socket option test" out of this set.
 - some cleanups.

This series significantly expands MPTCP socket option test coverage
by adding validation for 10 more socket options:

1. SO_REUSEADDR/SO_REUSEPORT - Test socket reuse capabilities
2. SO_BINDTODEVICE/SO_BINDTOIFINDEX - Validate interface binding
3. IP_TOS - Verify Type of Service handling
4. IP_FREEBIND - Test free address binding
5. IP_TRANSPARENT - Validate transparent proxying
6. IP_BIND_ADDRESS_NO_PORT - Test deferred port binding
7. IP_LOCAL_PORT_RANGE - Check local port range restriction
8. IPV6_V6ONLY - Verify IPv6-only sockets

Each commit systematically adds:
- Setsockopt/getsockopt operations in mptcp_sockopt.c
- Dedicated test cases in mptcp_sockopt.sh
- IPv4 and IPv6 coverage
- Error handling and edge case validation

The new tests verify that MPTCP correctly propagates socket options to
subflows and maintains consistent behavior across address families.

Link: https://github.com/multipath-tcp/mptcp_net-next/issues/525

Geliang Tang (10):
  selftests: mptcp: sockopt: improve test output clarity
  selftests: mptcp: sockopt: add SO_REUSEADDR test helper
  selftests: mptcp: sockopt: add SO_REUSEPORT test
  selftests: mptcp: sockopt: add SO_BINDTODEVICE test
  selftests: mptcp: sockopt: add SO_BINDTOIFINDEX test
  selftests: mptcp: sockopt: add IP_FREEBIND tests
  selftests: mptcp: sockopt: add IP_TRANSPARENT tests
  selftests: mptcp: sockopt: add IP_BIND_ADDRESS_NO_PORT test
  selftests: mptcp: sockopt: add IP_LOCAL_PORT_RANGE test
  selftests: mptcp: sockopt: add IPV6_V6ONLY test

 .../selftests/net/mptcp/mptcp_sockopt.c       | 257 +++++++++++++++++-
 .../selftests/net/mptcp/mptcp_sockopt.sh      |  37 ++-
 2 files changed, 282 insertions(+), 12 deletions(-)

-- 
2.48.1