This is supposed to be a backport for v4.14.y and older. Sorry for the confusion.
Guenter
On 06/17/2018 10:37 PM, Guenter Roeck wrote:
From: Eric Dumazet <edumazet@xxxxxxxxxx>
commit 02db55718d53f9d426cee504c27fb768e9ed4ffe upstream.
While rcvbuf is properly clamped by tcp_rmem[2], rcvwin
is left to a potentially too big value.
It has no serious effect, since :
1) tcp_grow_window() has very strict checks.
2) window_clamp can be mangled by user space to any value anyway.
tcp_init_buffer_space() and companions use tcp_full_space(),
we use tcp_win_from_space() to avoid reloading sk->sk_rcvbuf
Signed-off-by: Eric Dumazet <edumazet@xxxxxxxxxx>
Acked-by: Soheil Hassas Yeganeh <soheil@xxxxxxxxxx>
Acked-by: Wei Wang <weiwan@xxxxxxxxxx>
Acked-by: Neal Cardwell <ncardwell@xxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Guenter Roeck <linux@xxxxxxxxxxxx>
---
net/ipv4/tcp_input.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c
index 125b49c166a4..f0caff3139ed 100644
--- a/net/ipv4/tcp_input.c
+++ b/net/ipv4/tcp_input.c
@@ -647,7 +647,7 @@ void tcp_rcv_space_adjust(struct sock *sk)
sk->sk_rcvbuf = rcvbuf;
/* Make the window clamp follow along. */
- tp->window_clamp = rcvwin;
+ tp->window_clamp = tcp_win_from_space(rcvbuf);
}
}
tp->rcvq_space.space = copied;
