lkml.org 
[lkml]   [2019]   [Feb]   [25]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH 4.20 062/183] bpf: correctly set initial window on active Fast Open sender
Date
4.20-stable review patch.  If anyone has any objections, please let me know.

------------------

[ Upstream commit 31aa6503a15ba00182ea6dbbf51afb63bf9e851d ]

The existing BPF TCP initial congestion window (TCP_BPF_IW) does not
to work on (active) Fast Open sender. This is because it changes the
(initial) window only if data_segs_out is zero -- but data_segs_out
is also incremented on SYN-data. This patch fixes the issue by
proerly accounting for SYN-data additionally.

Fixes: fc7478103c84 ("bpf: Adds support for setting initial cwnd")
Signed-off-by: Yuchung Cheng <ycheng@google.com>
Reviewed-by: Neal Cardwell <ncardwell@google.com>
Acked-by: Lawrence Brakmo <brakmo@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
net/core/filter.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/net/core/filter.c b/net/core/filter.c
index eb0007f30142b..fa9452406f214 100644
--- a/net/core/filter.c
+++ b/net/core/filter.c
@@ -4019,7 +4019,7 @@ BPF_CALL_5(bpf_setsockopt, struct bpf_sock_ops_kern *, bpf_sock,
/* Only some options are supported */
switch (optname) {
case TCP_BPF_IW:
- if (val <= 0 || tp->data_segs_out > 0)
+ if (val <= 0 || tp->data_segs_out > tp->syn_data)
ret = -EINVAL;
else
tp->snd_cwnd = val;
--
2.19.1


\
 
 \ /
  Last update: 2019-02-25 22:32    [W:0.369 / U:9.624 seconds]
©2003-2018 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site