tcp: Respect SO_RCVLOWAT in tcp_poll().
Based upon a report by Vito Caputo.
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c
index 1ab341e..7d81a1e 100644
--- a/net/ipv4/tcp.c
+++ b/net/ipv4/tcp.c
@@ -384,13 +384,17 @@
/* Connected? */
if ((1 << sk->sk_state) & ~(TCPF_SYN_SENT | TCPF_SYN_RECV)) {
+ int target = sock_rcvlowat(sk, 0, INT_MAX);
+
+ if (tp->urg_seq == tp->copied_seq &&
+ !sock_flag(sk, SOCK_URGINLINE) &&
+ tp->urg_data)
+ target--;
+
/* Potential race condition. If read of tp below will
* escape above sk->sk_state, we can be illegally awaken
* in SYN_* states. */
- if ((tp->rcv_nxt != tp->copied_seq) &&
- (tp->urg_seq != tp->copied_seq ||
- tp->rcv_nxt != tp->copied_seq + 1 ||
- sock_flag(sk, SOCK_URGINLINE) || !tp->urg_data))
+ if (tp->rcv_nxt - tp->copied_seq >= target)
mask |= POLLIN | POLLRDNORM;
if (!(sk->sk_shutdown & SEND_SHUTDOWN)) {