tcp/dccp: fix behavior of stale SYN_RECV request sockets
authorEric Dumazet <edumazet@google.com>
Wed, 14 Oct 2015 00:12:54 +0000 (17:12 -0700)
committerDavid S. Miller <davem@davemloft.net>
Wed, 14 Oct 2015 01:26:34 +0000 (18:26 -0700)
commit4bdc3d66147b3a623b32216a45431d0cff005f50
tree2e3f5a76b0e11c05cd1e9e88f5ab0c5cc1efe344
parentbbb300eb976b613a8e4e666d3af39f5ab1031d22
tcp/dccp: fix behavior of stale SYN_RECV request sockets

When a TCP/DCCP listener is closed, its pending SYN_RECV request sockets
become stale, meaning 3WHS can not complete.

But current behavior is wrong :
incoming packets finding such stale sockets are dropped.

We need instead to cleanup the request socket and perform another
lookup :
- Incoming ACK will give a RST answer,
- SYN rtx might find another listener if available.
- We expedite cleanup of request sockets and old listener socket.

Fixes: 079096f103fa ("tcp/dccp: install syn_recv requests into ehash table")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
net/dccp/ipv4.c
net/dccp/ipv6.c
net/ipv4/tcp_ipv4.c
net/ipv6/tcp_ipv6.c