scsi: fcoe: fix null-ptr-deref Read in fc_release_transport

In fcoe_if_init, if fc_attach_transport(&fcoe_vport_fc_functions)
fails, need to free the previously memory and return fail, otherwise
will trigger null-ptr-deref Read in fc_release_transport.

fcoe_exit
  fcoe_if_exit
    fc_release_transport(fcoe_vport_scsi_transport)

Link: https://lore.kernel.org/r/1566279789-58207-1-git-send-email-zhengbin13@huawei.com
Reported-by: Hulk Robot <hulkci@huawei.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: zhengbin <zhengbin13@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

1 files changed, 11 insertions, 5 deletions

diff --git a/drivers/scsi/fcoe/fcoe.c b/drivers/scsi/fcoe/fcoe.c
index 8e217ab7646e..813f26d8b417 100644
--- a/drivers/scsi/fcoe/fcoe.c
+++ b/drivers/scsi/fcoe/fcoe.c
@@ -1250,15 +1250,21 @@ static int __init fcoe_if_init(void)
         /* attach to scsi transport */
         fcoe_nport_scsi_transport =
                 fc_attach_transport(&fcoe_nport_fc_functions);
+        if (!fcoe_nport_scsi_transport)
+                goto err;
+
         fcoe_vport_scsi_transport =
                 fc_attach_transport(&fcoe_vport_fc_functions);
-
-        if (!fcoe_nport_scsi_transport) {
-                printk(KERN_ERR "fcoe: Failed to attach to the FC transport\n");
-                return -ENODEV;
-        }
+        if (!fcoe_vport_scsi_transport)
+                goto err_vport;
 
         return 0;
+
+err_vport:
+        fc_release_transport(fcoe_nport_scsi_transport);
+err:
+        printk(KERN_ERR "fcoe: Failed to attach to the FC transport\n");
+        return -ENODEV;
 }
 
 /**