4.17-stable review patch. If anyone has any objections, please let me know.
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From: Santosh Shilimkar santosh.shilimkar@oracle.com
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 sowmini.varadhan@oracle.com Signed-off-by: Santosh Shilimkar santosh.shilimkar@oracle.com Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- net/rds/loop.c | 1 + net/rds/rds.h | 5 +++++ net/rds/recv.c | 5 +++++ 3 files changed, 11 insertions(+)
--- 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, }; --- a/net/rds/rds.h +++ b/net/rds/rds.h @@ -479,6 +479,11 @@ 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 * --- a/net/rds/recv.c +++ b/net/rds/recv.c @@ -103,6 +103,11 @@ static void rds_recv_rcvbuf_delta(struct 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 "