diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c index e48e28e7d539..4f8a8a17891a 100644 --- a/net/ipv4/tcp_output.c +++ b/net/ipv4/tcp_output.c @@ -1295,6 +1295,7 @@ static int tcp_mtu_probe(struct sock *sk) struct sk_buff *skb, *nskb, *next; int len; int probe_size; + int size_needed; unsigned int pif; int copy; int mss_now; @@ -1313,6 +1314,7 @@ static int tcp_mtu_probe(struct sock *sk) /* Very simple search strategy: just double the MSS. */ mss_now = tcp_current_mss(sk, 0); probe_size = 2*tp->mss_cache; + size_needed = probe_size + (tp->reordering + 1) * tp->mss_cache; if (probe_size > tcp_mtu_to_mss(sk, icsk->icsk_mtup.search_high)) { /* TODO: set timer for probe_converge_event */ return -1; @@ -1322,18 +1324,15 @@ static int tcp_mtu_probe(struct sock *sk) len = 0; if ((skb = tcp_send_head(sk)) == NULL) return -1; - while ((len += skb->len) < probe_size && !tcp_skb_is_last(sk, skb)) + while ((len += skb->len) < size_needed && !tcp_skb_is_last(sk, skb)) skb = tcp_write_queue_next(sk, skb); - if (len < probe_size) + if (len < size_needed) return -1; - /* Receive window check. */ - if (after(TCP_SKB_CB(skb)->seq + probe_size, tp->snd_una + tp->snd_wnd)) { - if (tp->snd_wnd < probe_size) - return -1; - else - return 0; - } + if (tp->snd_wnd < size_needed) + return -1; + if (after(tp->snd_nxt + size_needed, tp->snd_una + tp->snd_wnd)) + return 0; /* Do we need to wait to drain cwnd? */ pif = tcp_packets_in_flight(tp);