cnic: Randomize initial TCP port for iSCSI connections

This reduces the likelihood of port re-use when re-loading the driver.

Signed-off-by: Eddie Wai <eddie.wai@broadcom.com>
Signed-off-by: Michael Chan <mchan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/cnic.c

@@ -605,11 +605,12 @@ static int cnic_unregister_device(struct cnic_dev *dev, int ulp_type)
 }
 EXPORT_SYMBOL(cnic_unregister_driver);
 
-static int cnic_init_id_tbl(struct cnic_id_tbl *id_tbl, u32 size, u32 start_id)
+static int cnic_init_id_tbl(struct cnic_id_tbl *id_tbl, u32 size, u32 start_id,
+			    u32 next)
 {
 	id_tbl->start = start_id;
 	id_tbl->max = size;
-	id_tbl->next = 0;
+	id_tbl->next = next;
 	spin_lock_init(&id_tbl->lock);
 	id_tbl->table = kzalloc(DIV_ROUND_UP(size, 32) * 4, GFP_KERNEL);
 	if (!id_tbl->table)
@@ -3804,14 +3805,17 @@ static void cnic_cm_free_mem(struct cnic_dev *dev)
 static int cnic_cm_alloc_mem(struct cnic_dev *dev)
 {
 	struct cnic_local *cp = dev->cnic_priv;
+	u32 port_id;
 
 	cp->csk_tbl = kzalloc(sizeof(struct cnic_sock) * MAX_CM_SK_TBL_SZ,
 			      GFP_KERNEL);
 	if (!cp->csk_tbl)
 		return -ENOMEM;
 
+	get_random_bytes(&port_id, sizeof(port_id));
+	port_id %= CNIC_LOCAL_PORT_RANGE;
 	if (cnic_init_id_tbl(&cp->csk_port_tbl, CNIC_LOCAL_PORT_RANGE,
-			     CNIC_LOCAL_PORT_MIN)) {
+			     CNIC_LOCAL_PORT_MIN, port_id)) {
 		cnic_cm_free_mem(dev);
 		return -ENOMEM;
 	}
@@ -4829,7 +4833,7 @@ static int cnic_start_bnx2x_hw(struct cnic_dev *dev)
 	pfid = cp->pfid;
 
 	ret = cnic_init_id_tbl(&cp->cid_tbl, MAX_ISCSI_TBL_SZ,
-			       cp->iscsi_start_cid);
+			       cp->iscsi_start_cid, 0);
 
 	if (ret)
 		return -ENOMEM;
@@ -4837,7 +4841,7 @@ static int cnic_start_bnx2x_hw(struct cnic_dev *dev)
 	if (BNX2X_CHIP_IS_E2(cp->chip_id)) {
 		ret = cnic_init_id_tbl(&cp->fcoe_cid_tbl,
 					BNX2X_FCOE_NUM_CONNECTIONS,
-					cp->fcoe_start_cid);
+					cp->fcoe_start_cid, 0);
 
 		if (ret)
 			return -ENOMEM;