netdev - [PATCH net-next 1/2] rds: Use atomic flag to track connections being destroyed

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Thu,  4 Jan 2018 06:52:59 -0800
From:   Sowmini Varadhan <sowmini.varadhan@...cle.com>
To:     netdev@...r.kernel.org
Cc:     davem@...emloft.net, rds-devel@....oracle.com,
        sowmini.varadhan@...cle.com, santosh.shilimkar@...cle.com
Subject: [PATCH net-next 1/2] rds: Use atomic flag to track connections being destroyed

Replace c_destroy_in_prog by using a bit in cp_flags that
can set/tested atomically.

Signed-off-by: Sowmini Varadhan <sowmini.varadhan@...cle.com>
Acked-by: Santosh Shilimkar <santosh.shilimkar@...cle.com>
---
 net/rds/connection.c  |    7 ++++---
 net/rds/rds.h         |    4 ++--
 net/rds/tcp_connect.c |    2 +-
 3 files changed, 7 insertions(+), 6 deletions(-)

diff --git a/net/rds/connection.c b/net/rds/connection.c
index 6492c0b..1eed197 100644
--- a/net/rds/connection.c
+++ b/net/rds/connection.c
@@ -366,7 +366,7 @@ void rds_conn_shutdown(struct rds_conn_path *cp)
 	 * to the conn hash, so we never trigger a reconnect on this
 	 * conn - the reconnect is always triggered by the active peer. */
 	cancel_delayed_work_sync(&cp->cp_conn_w);
-	if (conn->c_destroy_in_prog)
+	if (test_bit(RDS_DESTROY_PENDING, &cp->cp_flags))
 		return;
 	rcu_read_lock();
 	if (!hlist_unhashed(&conn->c_hash_node)) {
@@ -384,6 +384,8 @@ static void rds_conn_path_destroy(struct rds_conn_path *cp)
 {
 	struct rds_message *rm, *rtmp;
 
+	set_bit(RDS_DESTROY_PENDING, &cp->cp_flags);
+
 	if (!cp->cp_transport_data)
 		return;
 
@@ -426,7 +428,6 @@ void rds_conn_destroy(struct rds_connection *conn)
 		 "%pI4\n", conn, &conn->c_laddr,
 		 &conn->c_faddr);
 
-	conn->c_destroy_in_prog = 1;
 	/* Ensure conn will not be scheduled for reconnect */
 	spin_lock_irq(&rds_conn_lock);
 	hlist_del_init_rcu(&conn->c_hash_node);
@@ -685,7 +686,7 @@ void rds_conn_path_drop(struct rds_conn_path *cp, bool destroy)
 {
 	atomic_set(&cp->cp_state, RDS_CONN_ERROR);
 
-	if (!destroy && cp->cp_conn->c_destroy_in_prog)
+	if (!destroy && test_bit(RDS_DESTROY_PENDING, &cp->cp_flags))
 		return;
 
 	queue_work(rds_wq, &cp->cp_down_w);
diff --git a/net/rds/rds.h b/net/rds/rds.h
index d09f6c1..374ae83 100644
--- a/net/rds/rds.h
+++ b/net/rds/rds.h
@@ -88,6 +88,7 @@ enum {
 #define RDS_RECONNECT_PENDING	1
 #define RDS_IN_XMIT		2
 #define RDS_RECV_REFILL		3
+#define	RDS_DESTROY_PENDING	4
 
 /* Max number of multipaths per RDS connection. Must be a power of 2 */
 #define	RDS_MPATH_WORKERS	8
@@ -139,8 +140,7 @@ struct rds_connection {
 	__be32			c_faddr;
 	unsigned int		c_loopback:1,
 				c_ping_triggered:1,
-				c_destroy_in_prog:1,
-				c_pad_to_32:29;
+				c_pad_to_32:30;
 	int			c_npaths;
 	struct rds_connection	*c_passive;
 	struct rds_transport	*c_trans;
diff --git a/net/rds/tcp_connect.c b/net/rds/tcp_connect.c
index 46f74da..534c67a 100644
--- a/net/rds/tcp_connect.c
+++ b/net/rds/tcp_connect.c
@@ -170,7 +170,7 @@ void rds_tcp_conn_path_shutdown(struct rds_conn_path *cp)
 		 cp->cp_conn, tc, sock);
 
 	if (sock) {
-		if (cp->cp_conn->c_destroy_in_prog)
+		if (test_bit(RDS_DESTROY_PENDING, &cp->cp_flags))
 			rds_tcp_set_linger(sock);
 		sock->ops->shutdown(sock, RCV_SHUTDOWN | SEND_SHUTDOWN);
 		lock_sock(sock->sk);
-- 
1.7.1