Kuniyuki Iwashima says:
====================
Improve bind(addr, 0) behaviour.
Currently we fail to bind sockets to ephemeral ports when all of the ports
are exhausted even if all sockets have SO_REUSEADDR enabled. In this case,
we still have a chance to connect to the different remote hosts.
These patches add net.ipv4.ip_autobind_reuse option and fix the behaviour
to fully utilize all space of the local (addr, port) tuples.
Changes in v5:
- Add more description to documents.
- Fix sysctl option to use proc_dointvec_minmax.
- Remove the Fixes: tag and squash two commits.
Changes in v4:
- Add net.ipv4.ip_autobind_reuse option to not change the current behaviour.
- Modify .gitignore for test.
https://lore.kernel.org/netdev/
20200308181615.90135-1-kuniyu@amazon.co.jp/
Changes in v3:
- Change the title and write more specific description of the 3rd patch.
- Add a test in tools/testing/selftests/net/ as the 4th patch.
https://lore.kernel.org/netdev/
20200229113554.78338-1-kuniyu@amazon.co.jp/
Changes in v2:
- Change the description of the 2nd patch ('localhost' -> 'address').
- Correct the description and the if statement of the 3rd patch.
https://lore.kernel.org/netdev/
20200226074631.67688-1-kuniyu@amazon.co.jp/
v1 with tests:
https://lore.kernel.org/netdev/
20200220152020.13056-1-kuniyu@amazon.co.jp/
====================
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>