A relatively common use case is to have several IPs configured on a host, and have different listeners for each of them. We would like to add a "catch all" listener on addr_any, to match incoming connections not served by any of the listeners bound to a specific address.
However, port-only lookups can match addr_any sockets when sockets listening on specific addresses are present if so_reuseport flag is set. This patchset eliminates lookups into port-only hashtable, as lookups by (addr,port) tuple are easily available. In a future patchset I plan to explore whether it is possible to remove port-only hashtables completely: additional refactoring will be required, as some non-lookup code uses the hashtables. Peter Oskolkov (5): net: udp: prefer listeners bound to an address net: udp6: prefer listeners bound to an address net: tcp: prefer listeners bound to an address net: tcp6: prefer listeners bound to an address selftests: net: test that listening sockets match on address properly net/ipv4/inet_hashtables.c | 60 +--- net/ipv4/udp.c | 76 ++--- net/ipv6/inet6_hashtables.c | 54 +--- net/ipv6/udp.c | 79 ++---- tools/testing/selftests/net/.gitignore | 1 + tools/testing/selftests/net/Makefile | 4 +- .../selftests/net/reuseport_addr_any.c | 264 ++++++++++++++++++ .../selftests/net/reuseport_addr_any.sh | 4 + 8 files changed, 325 insertions(+), 217 deletions(-) create mode 100644 tools/testing/selftests/net/reuseport_addr_any.c create mode 100755 tools/testing/selftests/net/reuseport_addr_any.sh -- 2.20.0.rc2.403.gdbc3b29805-goog
