If we receive data on a socket that's in repair mode, the sequence and contents of the receive queue we dump depend on the timing. We need to freeze the input queue, otherwise the connection parameters restored later might not match the actual state of the connection.
Patch 1/2 has the full details and the fix, patch 2/2 introduces selftests to illustrate the problem and verify the solution. Stefano Brivio (2): tcp: Don't accept data when socket is in repair mode selftests: Add data path tests for TCP_REPAIR mode include/net/dropreason-core.h | 3 + net/ipv4/tcp_input.c | 14 +- tools/testing/selftests/Makefile | 1 + .../selftests/net/tcp_repair/.gitignore | 3 + .../testing/selftests/net/tcp_repair/Makefile | 23 ++ .../testing/selftests/net/tcp_repair/client.c | 273 ++++++++++++++++++ .../testing/selftests/net/tcp_repair/inner.sh | 32 ++ .../testing/selftests/net/tcp_repair/outer.sh | 44 +++ tools/testing/selftests/net/tcp_repair/run.sh | 12 + .../testing/selftests/net/tcp_repair/server.c | 155 ++++++++++ tools/testing/selftests/net/tcp_repair/talk.h | 26 ++ 11 files changed, 585 insertions(+), 1 deletion(-) create mode 100644 tools/testing/selftests/net/tcp_repair/.gitignore create mode 100644 tools/testing/selftests/net/tcp_repair/Makefile create mode 100644 tools/testing/selftests/net/tcp_repair/client.c create mode 100755 tools/testing/selftests/net/tcp_repair/inner.sh create mode 100755 tools/testing/selftests/net/tcp_repair/outer.sh create mode 100755 tools/testing/selftests/net/tcp_repair/run.sh create mode 100644 tools/testing/selftests/net/tcp_repair/server.c create mode 100644 tools/testing/selftests/net/tcp_repair/talk.h -- 2.43.0
