diff options
| author | Andrew Vagin <avagin@openvz.org> | 2012-11-15 04:03:17 +0000 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2012-11-26 12:14:19 -0800 |
| commit | c6f7b86211233142300aeec7b1ab4ae640b81abd (patch) | |
| tree | 5b8f0580777fc714b9dd1597ee1bac61da701011 | |
| parent | a809dffbbbcfbac5f6e6e291e472ac3ca91e0ca2 (diff) | |
tcp: fix retransmission in repair mode
[ Upstream commit ec34232575083fd0f43d3a101e8ebb041b203761 ]
Currently if a socket was repaired with a few packet in a write queue,
a kernel bug may be triggered:
kernel BUG at net/ipv4/tcp_output.c:2330!
RIP: 0010:[<ffffffff8155784f>] tcp_retransmit_skb+0x5ff/0x610
According to the initial realization v3.4-rc2-963-gc0e88ff,
all skb-s should look like already posted. This patch fixes code
according with this sentence.
Here are three points, which were not done in the initial patch:
1. A tcp send head should not be changed
2. Initialize TSO state of a skb
3. Reset the retransmission time
This patch moves logic from tcp_sendmsg to tcp_write_xmit. A packet
passes the ussual way, but isn't sent to network. This patch solves
all described problems and handles tcp_sendpages.
Signed-off-by: Andrey Vagin <avagin@openvz.org>
Cc: Pavel Emelyanov <xemul@parallels.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>
Cc: James Morris <jmorris@namei.org>
Cc: Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org>
Cc: Patrick McHardy <kaber@trash.net>
Acked-by: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | net/ipv4/tcp.c | 4 | ||||
| -rw-r--r-- | net/ipv4/tcp_output.c | 4 |
2 files changed, 6 insertions, 2 deletions
diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c index 49dd99307815..b0b39f60495e 100644 --- a/net/ipv4/tcp.c +++ b/net/ipv4/tcp.c @@ -1236,7 +1236,7 @@ new_segment: wait_for_sndbuf: set_bit(SOCK_NOSPACE, &sk->sk_socket->flags); wait_for_memory: - if (copied && likely(!tp->repair)) + if (copied) tcp_push(sk, flags & ~MSG_MORE, mss_now, TCP_NAGLE_PUSH); if ((err = sk_stream_wait_memory(sk, &timeo)) != 0) @@ -1247,7 +1247,7 @@ wait_for_memory: } out: - if (copied && likely(!tp->repair)) + if (copied) tcp_push(sk, flags, mss_now, tp->nonagle); release_sock(sk); return copied + copied_syn; diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c index d04632673a9e..6735beaacbed 100644 --- a/net/ipv4/tcp_output.c +++ b/net/ipv4/tcp_output.c @@ -1977,6 +1977,9 @@ static bool tcp_write_xmit(struct sock *sk, unsigned int mss_now, int nonagle, tso_segs = tcp_init_tso_segs(sk, skb, mss_now); BUG_ON(!tso_segs); + if (unlikely(tp->repair) && tp->repair_queue == TCP_SEND_QUEUE) + goto repair; /* Skip network transmission */ + cwnd_quota = tcp_cwnd_test(tp, skb); if (!cwnd_quota) break; @@ -2017,6 +2020,7 @@ static bool tcp_write_xmit(struct sock *sk, unsigned int mss_now, int nonagle, if (unlikely(tcp_transmit_skb(sk, skb, 1, gfp))) break; +repair: /* Advance the send_head. This one is sent out. * This call will increment packets_out. */ |