From: Sowmini Varadhan Date: Wed, 18 May 2016 17:06:24 +0000 (-0700) Subject: RDS: TCP: Avoid rds connection churn from rogue SYNs X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=c948bb5c2cc4d63f9d76fc02baf5a8331e3cd27f;p=GitHub%2Fmoto-9609%2Fandroid_kernel_motorola_exynos9610.git RDS: TCP: Avoid rds connection churn from rogue SYNs When a rogue SYN is received after the connection arbitration algorithm has converged, the incoming SYN should not needlessly quiesce the transmit path, and it should not result in needless TCP connection resets due to re-execution of the connection arbitration logic. Signed-off-by: Sowmini Varadhan Acked-by: Santosh Shilimkar Signed-off-by: David S. Miller --- diff --git a/net/rds/tcp_listen.c b/net/rds/tcp_listen.c index 094a8cae0ef1..4bf4befe5066 100644 --- a/net/rds/tcp_listen.c +++ b/net/rds/tcp_listen.c @@ -132,11 +132,13 @@ int rds_tcp_accept_one(struct socket *sock) * so we must quiesce any send threads before resetting * c_transport_data. */ - wait_event(conn->c_waitq, - !test_bit(RDS_IN_XMIT, &conn->c_flags)); - if (ntohl(inet->inet_saddr) < ntohl(inet->inet_daddr)) { + if (ntohl(inet->inet_saddr) < ntohl(inet->inet_daddr) || + !conn->c_outgoing) { goto rst_nsk; - } else if (rs_tcp->t_sock) { + } else { + atomic_set(&conn->c_state, RDS_CONN_CONNECTING); + wait_event(conn->c_waitq, + !test_bit(RDS_IN_XMIT, &conn->c_flags)); rds_tcp_restore_callbacks(rs_tcp->t_sock, rs_tcp); conn->c_outgoing = 0; }