diff options
| author | Eric Dumazet <edumazet@google.com> | 2015-10-13 17:12:54 -0700 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2015-10-13 18:26:34 -0700 |
| commit | 4bdc3d66147b3a623b32216a45431d0cff005f50 (patch) | |
| tree | 2e3f5a76b0e11c05cd1e9e88f5ab0c5cc1efe344 /net/ipv4 | |
| parent | bbb300eb976b613a8e4e666d3af39f5ab1031d22 (diff) | |
| download | op-kernel-dev-4bdc3d66147b3a623b32216a45431d0cff005f50.zip op-kernel-dev-4bdc3d66147b3a623b32216a45431d0cff005f50.tar.gz | |
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>
Diffstat (limited to 'net/ipv4')
| -rw-r--r-- | net/ipv4/tcp_ipv4.c | 7 |
1 files changed, 6 insertions, 1 deletions
diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c index ddb1983..1ff0923 100644 --- a/net/ipv4/tcp_ipv4.c +++ b/net/ipv4/tcp_ipv4.c @@ -1572,6 +1572,7 @@ int tcp_v4_rcv(struct sk_buff *skb) TCP_SKB_CB(skb)->ip_dsfield = ipv4_get_dsfield(iph); TCP_SKB_CB(skb)->sacked = 0; +lookup: sk = __inet_lookup_skb(&tcp_hashinfo, skb, th->source, th->dest); if (!sk) goto no_tcp_socket; @@ -1587,8 +1588,12 @@ process: sk = req->rsk_listener; if (tcp_v4_inbound_md5_hash(sk, skb)) goto discard_and_relse; - if (sk->sk_state == TCP_LISTEN) + if (likely(sk->sk_state == TCP_LISTEN)) { nsk = tcp_check_req(sk, skb, req, false); + } else { + inet_csk_reqsk_queue_drop(sk, req); + goto lookup; + } if (!nsk) { reqsk_put(req); goto discard_it; |
