[PATCH AUTOSEL 5.3 34/89] RDMA/cm: Fix memory leak in cm_add/remove_one

[Sasha Levin]

From: Jack Morgenstein <jackm@xxxxxxxxxxxxxxxxxx>

[ Upstream commit 94635c36f3854934a46d9e812e028d4721bbb0e6 ]

In the process of moving the debug counters sysfs entries, the commit
mentioned below eliminated the cm_infiniband sysfs directory.

This sysfs directory was tied to the cm_port object allocated in procedure
cm_add_one().

Before the commit below, this cm_port object was freed via a call to
kobject_put(port->kobj) in procedure cm_remove_port_fs().

Since port no longer uses its kobj, kobject_put(port->kobj) was eliminated.
This, however, meant that kfree was never called for the cm_port buffers.

Fix this by adding explicit kfree(port) calls to functions cm_add_one()
and cm_remove_one().

Note: the kfree call in the first chunk below (in the cm_add_one error
flow) fixes an old, undetected memory leak.

Fixes: c87e65cfb97c ("RDMA/cm: Move debug counters to be under relevant IB device")
Link: https://lore.kernel.org/r/20190916071154.20383-2-leon@xxxxxxxxxx
Signed-off-by: Jack Morgenstein <jackm@xxxxxxxxxxxxxxxxxx>
Signed-off-by: Leon Romanovsky <leonro@xxxxxxxxxxxx>
Reviewed-by: Jason Gunthorpe <jgg@xxxxxxxxxxxx>
Signed-off-by: Jason Gunthorpe <jgg@xxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
 drivers/infiniband/core/cm.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/infiniband/core/cm.c b/drivers/infiniband/core/cm.c
index da10e6ccb43cd..5920c0085d35b 100644
--- a/drivers/infiniband/core/cm.c
+++ b/drivers/infiniband/core/cm.c
@@ -4399,6 +4399,7 @@ static void cm_add_one(struct ib_device *ib_device)
 error1:
 	port_modify.set_port_cap_mask = 0;
 	port_modify.clr_port_cap_mask = IB_PORT_CM_SUP;
+	kfree(port);
 	while (--i) {
 		if (!rdma_cap_ib_cm(ib_device, i))
 			continue;
@@ -4407,6 +4408,7 @@ static void cm_add_one(struct ib_device *ib_device)
 		ib_modify_port(ib_device, port->port_num, 0, &port_modify);
 		ib_unregister_mad_agent(port->mad_agent);
 		cm_remove_port_fs(port);
+		kfree(port);
 	}
 free:
 	kfree(cm_dev);
@@ -4460,6 +4462,7 @@ static void cm_remove_one(struct ib_device *ib_device, void *client_data)
 		spin_unlock_irq(&cm.state_lock);
 		ib_unregister_mad_agent(cur_mad_agent);
 		cm_remove_port_fs(port);
+		kfree(port);
 	}
 
 	kfree(cm_dev);
-- 
2.20.1