4.19-stable review patch. If anyone has any objections, please let me know.
------------------
From: Dinghao Liu <dinghao.liu@xxxxxxxxxx>
commit b481f644d9174670b385c3a699617052cd2a79d3 upstream.
When device_register() fails, zfcp_port_release() will be called after
put_device(). As a result, zfcp_ccw_adapter_put() will be called twice: one
in zfcp_port_release() and one in the error path after device_register().
So the reference on the adapter object is doubly put, which may lead to a
premature free. Fix this by adjusting the error tag after
device_register().
Fixes: f3450c7b9172 ("[SCSI] zfcp: Replace local reference counting with common kref")
Signed-off-by: Dinghao Liu <dinghao.liu@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20230923103723.10320-1-dinghao.liu@xxxxxxxxxx
Acked-by: Benjamin Block <bblock@xxxxxxxxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx # v2.6.33+
Signed-off-by: Martin K. Petersen <martin.petersen@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/s390/scsi/zfcp_aux.c | 9 +++++----
1 file changed, 5 insertions(+), 4 deletions(-)
--- a/drivers/s390/scsi/zfcp_aux.c
+++ b/drivers/s390/scsi/zfcp_aux.c
@@ -493,12 +493,12 @@ struct zfcp_port *zfcp_port_enqueue(stru
if (port) {
put_device(&port->dev);
retval = -EEXIST;
- goto err_out;
+ goto err_put;
}
port = kzalloc(sizeof(struct zfcp_port), GFP_KERNEL);
if (!port)
- goto err_out;
+ goto err_put;
rwlock_init(&port->unit_list_lock);
INIT_LIST_HEAD(&port->unit_list);
@@ -521,7 +521,7 @@ struct zfcp_port *zfcp_port_enqueue(stru
if (dev_set_name(&port->dev, "0x%016llx", (unsigned long long)wwpn)) {
kfree(port);
- goto err_out;
+ goto err_put;
}
retval = -EINVAL;
@@ -538,8 +538,9 @@ struct zfcp_port *zfcp_port_enqueue(stru
return port;
-err_out:
+err_put:
zfcp_ccw_adapter_put(adapter);
+err_out:
return ERR_PTR(retval);
}
