tcp: refine sk_rcvbuf increase for ooo packets

tcp: refine sk_rcvbuf increase for ooo packets

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 <edumazet@google.com>
Link: https://patch.msgid.link/20250707213900.1543248-2-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>