From a4b57440d971f4ee139a923a0b953f91c3769d70 Mon Sep 17 00:00:00 2001 From: Santosh Shilimkar Date: Thu, 14 Jun 2018 11:52:34 -0700 Subject: [PATCH] rds: avoid unenecessary cong_update in loop transport commit f1693c63ab133d16994cc50f773982b5905af264 upstream. Loop transport which is self loopback, remote port congestion update isn't relevant. Infact the xmit path already ignores it. Receive path needs to do the same. Reported-by: syzbot+4c20b3866171ce8441d2@syzkaller.appspotmail.com Reviewed-by: Sowmini Varadhan Signed-off-by: Santosh Shilimkar Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- net/rds/loop.c | 1 + net/rds/rds.h | 5 +++++ net/rds/recv.c | 5 +++++ 3 files changed, 11 insertions(+) diff --git a/net/rds/loop.c b/net/rds/loop.c index f2bf78de5688..dac6218a460e 100644 --- a/net/rds/loop.c +++ b/net/rds/loop.c @@ -193,4 +193,5 @@ struct rds_transport rds_loop_transport = { .inc_copy_to_user = rds_message_inc_copy_to_user, .inc_free = rds_loop_inc_free, .t_name = "loopback", + .t_type = RDS_TRANS_LOOP, }; diff --git a/net/rds/rds.h b/net/rds/rds.h index d09f6c1facb4..f685d8b514e5 100644 --- a/net/rds/rds.h +++ b/net/rds/rds.h @@ -454,6 +454,11 @@ struct rds_notifier { int n_status; }; +/* Available as part of RDS core, so doesn't need to participate + * in get_preferred transport etc + */ +#define RDS_TRANS_LOOP 3 + /** * struct rds_transport - transport specific behavioural hooks * diff --git a/net/rds/recv.c b/net/rds/recv.c index 555f07ccf0dc..c27cceae52e1 100644 --- a/net/rds/recv.c +++ b/net/rds/recv.c @@ -103,6 +103,11 @@ static void rds_recv_rcvbuf_delta(struct rds_sock *rs, struct sock *sk, rds_stats_add(s_recv_bytes_added_to_socket, delta); else rds_stats_add(s_recv_bytes_removed_from_socket, -delta); + + /* loop transport doesn't send/recv congestion updates */ + if (rs->rs_transport->t_type == RDS_TRANS_LOOP) + return; + now_congested = rs->rs_rcv_bytes > rds_sk_rcvbuf(rs); rdsdebug("rs %p (%pI4:%u) recv bytes %d buf %d "