When a passive flow has not been accepted yet, it is not wise to increase sk_rcvbuf when receiving ooo packets. A very busy server might tune down tcp_rmem[1] to better control how much memory can be used by sockets waiting in its listeners accept queues. Fixes: 63ad7dfedfae ("tcp: adjust rcvbuf in presence of reorders") Signed-off-by: Eric Dumazet --- net/ipv4/tcp_input.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c index 12c2e6fc85c62304565e4f2f8d22a916cf73db0c..68bc79eb90197b1bf3e8f5ddfc8762cf331ca1c7 100644 --- a/net/ipv4/tcp_input.c +++ b/net/ipv4/tcp_input.c @@ -5181,7 +5181,9 @@ static void tcp_data_queue_ofo(struct sock *sk, struct sk_buff *skb) skb_condense(skb); skb_set_owner_r(skb, sk); } - tcp_rcvbuf_grow(sk); + /* do not grow rcvbuf for not-yet-accepted or orphaned sockets. */ + if (sk->sk_socket) + tcp_rcvbuf_grow(sk); } static int __must_check tcp_queue_rcv(struct sock *sk, struct sk_buff *skb, -- 2.50.0.727.gbf7dc18ff4-goog