ses: fix additional element traversal bug

KASAN found that our additional element processing scripts drop off
the end of the VPD page into unallocated space.  The reason is that
not every element has additional information but our traversal
routines think they do, leading to them expecting far more additional
information than is present.  Fix this by adding a gate to the
traversal routine so that it only processes elements that are expected
to have additional information (list is in SES-2 section 6.1.13.1:
Additional Element Status diagnostic page overview)

Reported-by: Pavel Tikhomirov <ptikhomirov@virtuozzo.com>
Tested-by: Pavel Tikhomirov <ptikhomirov@virtuozzo.com>
Cc: stable@vger.kernel.org
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
This commit is contained in:
James Bottomley 2015-12-11 09:16:38 -08:00
parent 3417c1b5cb
commit 5e1033561d
2 changed files with 13 additions and 1 deletions

View File

@ -559,7 +559,15 @@ static void ses_enclosure_data_process(struct enclosure_device *edev,
if (desc_ptr)
desc_ptr += len;
if (addl_desc_ptr)
if (addl_desc_ptr &&
/* only find additional descriptions for specific devices */
(type_ptr[0] == ENCLOSURE_COMPONENT_DEVICE ||
type_ptr[0] == ENCLOSURE_COMPONENT_ARRAY_DEVICE ||
type_ptr[0] == ENCLOSURE_COMPONENT_SAS_EXPANDER ||
/* these elements are optional */
type_ptr[0] == ENCLOSURE_COMPONENT_SCSI_TARGET_PORT ||
type_ptr[0] == ENCLOSURE_COMPONENT_SCSI_INITIATOR_PORT ||
type_ptr[0] == ENCLOSURE_COMPONENT_CONTROLLER_ELECTRONICS))
addl_desc_ptr += addl_desc_ptr[1] + 2;
}

View File

@ -29,7 +29,11 @@
/* A few generic types ... taken from ses-2 */
enum enclosure_component_type {
ENCLOSURE_COMPONENT_DEVICE = 0x01,
ENCLOSURE_COMPONENT_CONTROLLER_ELECTRONICS = 0x07,
ENCLOSURE_COMPONENT_SCSI_TARGET_PORT = 0x14,
ENCLOSURE_COMPONENT_SCSI_INITIATOR_PORT = 0x15,
ENCLOSURE_COMPONENT_ARRAY_DEVICE = 0x17,
ENCLOSURE_COMPONENT_SAS_EXPANDER = 0x18,
};
/* ses-2 common element status */