[PATCH] libosd: Fix NULL dereference BUG when target is none OSD conformant

[Boaz Harrosh <bharrosh@panasas.com>]

Very old OSC's Target had a BUG in the Get/Set attributes where
it was looking in the wrong places for attribute lists length.
If used with the open-osd initiator, the initiator would dereference
a NULL pointer when retrieving system_information attributes.

Checks are added if retrieval of each attributes was successful
before accessing them.

Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
---
 drivers/scsi/osd/osd_initiator.c |   11 +++++++----
 1 files changed, 7 insertions(+), 4 deletions(-)

diff --git a/drivers/scsi/osd/osd_initiator.c b/drivers/scsi/osd/osd_initiator.c
index eeaec3e..1696130 100644
--- a/drivers/scsi/osd/osd_initiator.c
+++ b/drivers/scsi/osd/osd_initiator.c
@@ -131,7 +131,7 @@ static int _osd_print_system_info(struct osd_dev *od, void *caps)
 
 	pFirst = get_attrs[a++].val_ptr;
 	OSD_INFO("PRODUCT_REVISION_LEVEL [%u]\n",
-		get_unaligned_be32(pFirst));
+		pFirst ? get_unaligned_be32(pFirst) : ~0U);
 
 	pFirst = get_attrs[a++].val_ptr;
 	OSD_INFO("PRODUCT_SERIAL_NUMBER  [%s]\n",
@@ -143,15 +143,18 @@ static int _osd_print_system_info(struct osd_dev *od, void *caps)
 
 	pFirst = get_attrs[a++].val_ptr;
 	OSD_INFO("TOTAL_CAPACITY         [0x%llx]\n",
-		_LLU(get_unaligned_be64(pFirst)));
+		pFirst ? _LLU(get_unaligned_be64(pFirst)) : ~0ULL);
 
 	pFirst = get_attrs[a++].val_ptr;
 	OSD_INFO("USED_CAPACITY          [0x%llx]\n",
-		_LLU(get_unaligned_be64(pFirst)));
+		pFirst ? _LLU(get_unaligned_be64(pFirst)) : ~0ULL);
 
 	pFirst = get_attrs[a++].val_ptr;
 	OSD_INFO("NUMBER_OF_PARTITIONS   [%llu]\n",
-		_LLU(get_unaligned_be64(pFirst)));
+		pFirst ? _LLU(get_unaligned_be64(pFirst)) : ~0ULL);
+
+	if (a >= nelem)
+		goto out;
 
 	/* FIXME: Where are the time utilities */
 	pFirst = get_attrs[a++].val_ptr;
-- 
1.6.0.1