netdev - [PATCH v2 net-next 0/2] tcp/dccp: better use of ephemeral ports

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite for Android: free password hash cracker in your pocket

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Date:	Thu, 11 Feb 2016 16:28:48 -0800
From:	Eric Dumazet <edumazet@...gle.com>
To:	"David S . Miller" <davem@...emloft.net>
Cc:	netdev <netdev@...r.kernel.org>,
	Eric Dumazet <edumazet@...gle.com>,
	Eric Dumazet <eric.dumazet@...il.com>
Subject: [PATCH v2 net-next 0/2] tcp/dccp: better use of ephemeral ports

Big servers have bloated bind table, making very hard to succeed
ephemeral port allocations, without special containers/namespace tricks.

This patch series extends the strategy added in commit 07f4c90062f8 
("tcp/dccp: try to not exhaust ip_local_port_range in connect()").

Since ports used by connect() are much likely to be shared among them,
we give a hint to both bind() and connect() to keep the crowds separated
if possible.

Of course, if on a specific host an application needs to allocate ~30000
ports using bind(), it will still be able to do so. Same for ~30000 connect()
to a unique 2-tuple (dst addr, dst port)

New implemetation is also more friendly to softirqs and reschedules.

v2: rebase after TCP SO_REUSEPORT changes

Eric Dumazet (2):
  tcp/dccp: better use of ephemeral ports in connect()
  tcp/dccp: better use of ephemeral ports in bind()

 net/ipv4/inet_connection_sock.c | 240 +++++++++++++++++++---------------------
 net/ipv4/inet_hashtables.c      | 170 ++++++++++++++--------------
 2 files changed, 199 insertions(+), 211 deletions(-)

-- 
2.7.0.rc3.207.g0ac5344