[PATCH] scsi: mpt3sas: Fix sas_device refcount leak when add transport port failed

[Xiyu Yang]

The reference counting issue happens in several exception handling paths
of mpt3sas_transport_port_add(). When those error scenarios occur such
as allocating sas port failed, the function forgets to decrease the
refcount of "sas_device" increased by mpt3sas_get_sdev_by_addr(),
causing a refcount leak.

Fix this issue by jumping to "out_device_put" label when error occurred.

Signed-off-by: Xiyu Yang <xiyuyang19@xxxxxxxxxxxx>
Signed-off-by: Xin Tan <tanxin.ctf@xxxxxxxxx>
---
 drivers/scsi/mpt3sas/mpt3sas_transport.c | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/drivers/scsi/mpt3sas/mpt3sas_transport.c b/drivers/scsi/mpt3sas/mpt3sas_transport.c
index 0681daee6c14..089aa2321d0f 100644
--- a/drivers/scsi/mpt3sas/mpt3sas_transport.c
+++ b/drivers/scsi/mpt3sas/mpt3sas_transport.c
@@ -782,13 +782,13 @@ mpt3sas_transport_port_add(struct MPT3SAS_ADAPTER *ioc, u16 handle,
 	if (!sas_node->parent_dev) {
 		ioc_err(ioc, "failure at %s:%d/%s()!\n",
 			__FILE__, __LINE__, __func__);
-		goto out_fail;
+		goto out_device_put;
 	}
 	port = sas_port_alloc_num(sas_node->parent_dev);
 	if ((sas_port_add(port))) {
 		ioc_err(ioc, "failure at %s:%d/%s()!\n",
 			__FILE__, __LINE__, __func__);
-		goto out_fail;
+		goto out_device_put;
 	}
 
 	list_for_each_entry(mpt3sas_phy, &mpt3sas_port->phy_list,
@@ -855,6 +855,11 @@ mpt3sas_transport_port_add(struct MPT3SAS_ADAPTER *ioc, u16 handle,
 		    rphy_to_expander_device(rphy), hba_port->port_id);
 	return mpt3sas_port;
 
+ out_device_put:
+	if (mpt3sas_port->remote_identify.device_type == SAS_END_DEVICE) {
+		sas_device->pend_sas_rphy_add = 0;
+		sas_device_put(sas_device);
+	}
  out_fail:
 	list_for_each_entry_safe(mpt3sas_phy, next, &mpt3sas_port->phy_list,
 	    port_siblings)
-- 
2.7.4