[PATCH AUTOSEL 5.15 28/31] scsi: iscsi: Fix possible memory leak when device_register() failed

From: Sasha Levin
Date: Wed Nov 23 2022 - 07:49:45 EST


From: Zhou Guanghui <zhouguanghui1@xxxxxxxxxx>

[ Upstream commit f014165faa7b953b81dcbf18835936e5f8d01f2a ]

If device_register() returns error, the name allocated by the
dev_set_name() need be freed. As described in the comment of
device_register(), we should use put_device() to give up the reference in
the error path.

Fix this by calling put_device(), the name will be freed in the
kobject_cleanup(), and this patch modified resources will be released by
calling the corresponding callback function in the device_release().

Signed-off-by: Zhou Guanghui <zhouguanghui1@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20221110033729.1555-1-zhouguanghui1@xxxxxxxxxx
Reviewed-by: Mike Christie <michael.christie@xxxxxxxxxx>
Signed-off-by: Martin K. Petersen <martin.petersen@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/scsi/scsi_transport_iscsi.c | 31 +++++++++++++++--------------
1 file changed, 16 insertions(+), 15 deletions(-)

diff --git a/drivers/scsi/scsi_transport_iscsi.c b/drivers/scsi/scsi_transport_iscsi.c
index f46ae5391758..cc39cbef9d7f 100644
--- a/drivers/scsi/scsi_transport_iscsi.c
+++ b/drivers/scsi/scsi_transport_iscsi.c
@@ -232,7 +232,7 @@ iscsi_create_endpoint(int dd_size)
dev_set_name(&ep->dev, "ep-%d", id);
err = device_register(&ep->dev);
if (err)
- goto free_id;
+ goto put_dev;

err = sysfs_create_group(&ep->dev.kobj, &iscsi_endpoint_group);
if (err)
@@ -246,10 +246,12 @@ iscsi_create_endpoint(int dd_size)
device_unregister(&ep->dev);
return NULL;

-free_id:
+put_dev:
mutex_lock(&iscsi_ep_idr_mutex);
idr_remove(&iscsi_ep_idr, id);
mutex_unlock(&iscsi_ep_idr_mutex);
+ put_device(&ep->dev);
+ return NULL;
free_ep:
kfree(ep);
return NULL;
@@ -767,7 +769,7 @@ iscsi_create_iface(struct Scsi_Host *shost, struct iscsi_transport *transport,

err = device_register(&iface->dev);
if (err)
- goto free_iface;
+ goto put_dev;

err = sysfs_create_group(&iface->dev.kobj, &iscsi_iface_group);
if (err)
@@ -781,9 +783,8 @@ iscsi_create_iface(struct Scsi_Host *shost, struct iscsi_transport *transport,
device_unregister(&iface->dev);
return NULL;

-free_iface:
- put_device(iface->dev.parent);
- kfree(iface);
+put_dev:
+ put_device(&iface->dev);
return NULL;
}
EXPORT_SYMBOL_GPL(iscsi_create_iface);
@@ -1252,15 +1253,15 @@ iscsi_create_flashnode_sess(struct Scsi_Host *shost, int index,

err = device_register(&fnode_sess->dev);
if (err)
- goto free_fnode_sess;
+ goto put_dev;

if (dd_size)
fnode_sess->dd_data = &fnode_sess[1];

return fnode_sess;

-free_fnode_sess:
- kfree(fnode_sess);
+put_dev:
+ put_device(&fnode_sess->dev);
return NULL;
}
EXPORT_SYMBOL_GPL(iscsi_create_flashnode_sess);
@@ -1300,15 +1301,15 @@ iscsi_create_flashnode_conn(struct Scsi_Host *shost,

err = device_register(&fnode_conn->dev);
if (err)
- goto free_fnode_conn;
+ goto put_dev;

if (dd_size)
fnode_conn->dd_data = &fnode_conn[1];

return fnode_conn;

-free_fnode_conn:
- kfree(fnode_conn);
+put_dev:
+ put_device(&fnode_conn->dev);
return NULL;
}
EXPORT_SYMBOL_GPL(iscsi_create_flashnode_conn);
@@ -4838,7 +4839,7 @@ iscsi_register_transport(struct iscsi_transport *tt)
dev_set_name(&priv->dev, "%s", tt->name);
err = device_register(&priv->dev);
if (err)
- goto free_priv;
+ goto put_dev;

err = sysfs_create_group(&priv->dev.kobj, &iscsi_transport_group);
if (err)
@@ -4873,8 +4874,8 @@ iscsi_register_transport(struct iscsi_transport *tt)
unregister_dev:
device_unregister(&priv->dev);
return NULL;
-free_priv:
- kfree(priv);
+put_dev:
+ put_device(&priv->dev);
return NULL;
}
EXPORT_SYMBOL_GPL(iscsi_register_transport);
--
2.35.1