rds: tcp: various endian-ness fixes

Found when testing between sparc and x86 machines on different
subnets, so the address comparison patterns hit the corner cases and
brought out some bugs fixed by this patch.
Signed-off-by: Sowmini Varadhan <sowmini.varadhan@oracle.com>
Tested-by: Imanti Mendez <imanti.mendez@oracle.com>
Acked-by: Santosh Shilimkar <santosh.shilimkar@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/rds/rds.h

@@ -92,6 +92,8 @@ enum {
 #define	RDS_MPATH_HASH(rs, n) (jhash_1word((rs)->rs_bound_port, \
 			       (rs)->rs_hash_initval) & ((n) - 1))
 
+#define IS_CANONICAL(laddr, faddr) (htonl(laddr) < htonl(faddr))
+
 /* Per mpath connection state */
 struct rds_conn_path {
 	struct rds_connection	*cp_conn;

net/rds/recv.c

@@ -215,10 +215,10 @@ static void rds_recv_hs_exthdrs(struct rds_header *hdr,
 		switch (type) {
 		case RDS_EXTHDR_NPATHS:
 			conn->c_npaths = min_t(int, RDS_MPATH_WORKERS,
-					       buffer.rds_npaths);
+					       be16_to_cpu(buffer.rds_npaths));
 			break;
 		case RDS_EXTHDR_GEN_NUM:
-			new_peer_gen_num = buffer.rds_gen_num;
+			new_peer_gen_num = be32_to_cpu(buffer.rds_gen_num);
 			break;
 		default:
 			pr_warn_ratelimited("ignoring unknown exthdr type "
@@ -254,7 +254,8 @@ static void rds_start_mprds(struct rds_connection *conn)
 	int i;
 	struct rds_conn_path *cp;
 
-	if (conn->c_npaths > 1 && conn->c_laddr < conn->c_faddr) {
+	if (conn->c_npaths > 1 &&
+	    IS_CANONICAL(conn->c_laddr, conn->c_faddr)) {
 		for (i = 1; i < conn->c_npaths; i++) {
 			cp = &conn->c_path[i];
 			rds_conn_path_connect_if_down(cp);
@@ -339,14 +340,15 @@ void rds_recv_incoming(struct rds_connection *conn, __be32 saddr, __be32 daddr,
 		rds_stats_inc(s_recv_ping);
 		rds_send_pong(cp, inc->i_hdr.h_sport);
 		/* if this is a handshake ping, start multipath if necessary */
-		if (RDS_HS_PROBE(inc->i_hdr.h_sport, inc->i_hdr.h_dport)) {
+		if (RDS_HS_PROBE(be16_to_cpu(inc->i_hdr.h_sport),
+				 be16_to_cpu(inc->i_hdr.h_dport))) {
 			rds_recv_hs_exthdrs(&inc->i_hdr, cp->cp_conn);
 			rds_start_mprds(cp->cp_conn);
 		}
 		goto out;
 	}
 
-	if (inc->i_hdr.h_dport ==  RDS_FLAG_PROBE_PORT &&
+	if (be16_to_cpu(inc->i_hdr.h_dport) ==  RDS_FLAG_PROBE_PORT &&
 	    inc->i_hdr.h_sport == 0) {
 		rds_recv_hs_exthdrs(&inc->i_hdr, cp->cp_conn);
 		/* if this is a handshake pong, start multipath if necessary */

net/rds/send.c

@@ -1246,15 +1246,17 @@ rds_send_probe(struct rds_conn_path *cp, __be16 sport,
 	rm->m_inc.i_hdr.h_flags |= h_flags;
 	cp->cp_next_tx_seq++;
 
-	if (RDS_HS_PROBE(sport, dport) && cp->cp_conn->c_trans->t_mp_capable) {
-		u16 npaths = RDS_MPATH_WORKERS;
+	if (RDS_HS_PROBE(be16_to_cpu(sport), be16_to_cpu(dport)) &&
+	    cp->cp_conn->c_trans->t_mp_capable) {
+		u16 npaths = cpu_to_be16(RDS_MPATH_WORKERS);
+		u32 my_gen_num = cpu_to_be32(cp->cp_conn->c_my_gen_num);
 
 		rds_message_add_extension(&rm->m_inc.i_hdr,
 					  RDS_EXTHDR_NPATHS, &npaths,
 					  sizeof(npaths));
 		rds_message_add_extension(&rm->m_inc.i_hdr,
 					  RDS_EXTHDR_GEN_NUM,
-					  &cp->cp_conn->c_my_gen_num,
+					  &my_gen_num,
 					  sizeof(u32));
 	}
 	spin_unlock_irqrestore(&cp->cp_lock, flags);
@@ -1293,5 +1295,6 @@ rds_send_ping(struct rds_connection *conn)
 	}
 	conn->c_ping_triggered = 1;
 	spin_unlock_irqrestore(&cp->cp_lock, flags);
-	rds_send_probe(&conn->c_path[0], RDS_FLAG_PROBE_PORT, 0, 0);
+	rds_send_probe(&conn->c_path[0], cpu_to_be16(RDS_FLAG_PROBE_PORT),
+		       0, 0);
 }

net/rds/tcp_connect.c

@@ -66,7 +66,7 @@ void rds_tcp_state_change(struct sock *sk)
 		 * RDS connection as RDS_CONN_UP until the reconnect,
 		 * to avoid RDS datagram loss.
 		 */
-		if (cp->cp_conn->c_laddr > cp->cp_conn->c_faddr &&
+		if (!IS_CANONICAL(cp->cp_conn->c_laddr, cp->cp_conn->c_faddr) &&
 		    rds_conn_path_transition(cp, RDS_CONN_CONNECTING,
 					     RDS_CONN_ERROR)) {
 			rds_conn_path_drop(cp);

net/rds/tcp_listen.c

@@ -83,7 +83,7 @@ static
 struct rds_tcp_connection *rds_tcp_accept_one_path(struct rds_connection *conn)
 {
 	int i;
-	bool peer_is_smaller = (conn->c_faddr < conn->c_laddr);
+	bool peer_is_smaller = IS_CANONICAL(conn->c_faddr, conn->c_laddr);
 	int npaths = max_t(int, 1, conn->c_npaths);
 
 	/* for mprds, all paths MUST be initiated by the peer

net/rds/threads.c

@@ -127,7 +127,7 @@ void rds_queue_reconnect(struct rds_conn_path *cp)
 
 	/* let peer with smaller addr initiate reconnect, to avoid duels */
 	if (conn->c_trans->t_type == RDS_TRANS_TCP &&
-	    conn->c_laddr > conn->c_faddr)
+	    !IS_CANONICAL(conn->c_laddr, conn->c_faddr))
 		return;
 
 	set_bit(RDS_RECONNECT_PENDING, &cp->cp_flags);
@@ -156,7 +156,8 @@ void rds_connect_worker(struct work_struct *work)
 	struct rds_connection *conn = cp->cp_conn;
 	int ret;
 
-	if (cp->cp_index > 0 && cp->cp_conn->c_laddr > cp->cp_conn->c_faddr)
+	if (cp->cp_index > 0 &&
+	    !IS_CANONICAL(cp->cp_conn->c_laddr, cp->cp_conn->c_faddr))
 		return;
 	clear_bit(RDS_RECONNECT_PENDING, &cp->cp_flags);
 	ret = rds_conn_path_transition(cp, RDS_CONN_DOWN, RDS_CONN_CONNECTING);