From: zhengbin <zhengbin13@huawei.com>
Date: Tue, 20 Aug 2019 13:43:09 +0800
Subject: [PATCH] scsi: fcoe: fix null-ptr-deref Read in fc_release_transport
Git-commit: f96d279f0a5e53f4b96b16a5c08e2c75e139ba0b
Patch-mainline: v5.4-rc1
References: bsc#1156419,jsc#SLE-8281

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>
Acked-by: Hannes Reinecke <hare@suse.com>
---
 drivers/scsi/fcoe/fcoe.c | 16 +++++++++++-----
 1 file 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;
 }
 
 /**
-- 
2.16.4