tcp: Fix recvmsg MSG_PEEK influence of blocking behavior.

Vito Caputo noticed that tcp_recvmsg() returns immediately from
partial reads when MSG_PEEK is used.  In particular, this means that
SO_RCVLOWAT is not respected.

Simply remove the test.  And this matches the behavior of several
other systems, including BSD.

Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c
index eccb7165a80c180f56c42a1261597b361966396d..c5aca0bb116ae36ead0a824236ab4a5df9162d74 100644 (file)
--- a/net/ipv4/tcp.c
+++ b/net/ipv4/tcp.c
@@ -1374,8 +1374,7 @@ int tcp_recvmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg,
                            sk->sk_state == TCP_CLOSE ||
                            (sk->sk_shutdown & RCV_SHUTDOWN) ||
                            !timeo ||
-                           signal_pending(current) ||
-                           (flags & MSG_PEEK))
+                           signal_pending(current))
                                break;
                } else {
                        if (sock_flag(sk, SOCK_DONE))