From ed09dcc8bd7fe0991af7737e675996cbd022f38f Mon Sep 17 00:00:00 2001
From: Dan Williams <dan.j.williams@intel.com>
Date: Tue, 30 Dec 2014 14:46:14 -0800
Subject: ses: close potential registration race

The slot and address fields have a small window of instability when
userspace can read them before initialization. Separate
enclosure_component
allocation from registration.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
Reviewed-by: Jens Axboe <axboe@fb.com>
Cc: Hannes Reinecke <hare@suse.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>
---
 drivers/scsi/ses.c | 21 ++++++++++++++-------
 1 file changed, 14 insertions(+), 7 deletions(-)

(limited to 'drivers/scsi/ses.c')

diff --git a/drivers/scsi/ses.c b/drivers/scsi/ses.c
index b7e79e7646ad..7dd9cf558380 100644
--- a/drivers/scsi/ses.c
+++ b/drivers/scsi/ses.c
@@ -423,16 +423,23 @@ static void ses_enclosure_data_process(struct enclosure_device *edev,
 			    type_ptr[0] == ENCLOSURE_COMPONENT_ARRAY_DEVICE) {
 
 				if (create)
-					ecomp =	enclosure_component_register(edev,
-									     components++,
-									     type_ptr[0],
-									     name);
+					ecomp =	enclosure_component_alloc(
+						edev,
+						components++,
+						type_ptr[0],
+						name);
 				else
 					ecomp = &edev->component[components++];
 
-				if (!IS_ERR(ecomp) && addl_desc_ptr)
-					ses_process_descriptor(ecomp,
-							       addl_desc_ptr);
+				if (!IS_ERR(ecomp)) {
+					if (addl_desc_ptr)
+						ses_process_descriptor(
+							ecomp,
+							addl_desc_ptr);
+					if (create)
+						enclosure_component_register(
+							ecomp);
+				}
 			}
 			if (desc_ptr)
 				desc_ptr += len;
-- 
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