scsi: qla2xxx: Fix incorrect region-size setting in optrom SYSFS routines

commit 5cbdae10 upstream.

Commit e6f77540 ("scsi: qla2xxx: Fix an integer overflow in sysfs
code") incorrectly set 'optrom_region_size' to 'start+size', which can
overflow option-rom boundaries when 'start' is non-zero.  Continue setting
optrom_region_size to the proper adjusted value of 'size'.

Fixes: e6f77540 ("scsi: qla2xxx: Fix an integer overflow in sysfs code")
Cc: stable@vger.kernel.org
Signed-off-by: Andrew Vasquez <andrewv@marvell.com>
Signed-off-by: Himanshu Madhani <hmadhani@marvell.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/scsi/qla2xxx/qla_attr.c

@@ -364,7 +364,7 @@ qla2x00_sysfs_write_optrom_ctl(struct file *filp, struct kobject *kobj,
 		}
 
 		ha->optrom_region_start = start;
-		ha->optrom_region_size = start + size;
+		ha->optrom_region_size = size;
 
 		ha->optrom_state = QLA_SREADING;
 		ha->optrom_buffer = vmalloc(ha->optrom_region_size);
@@ -437,7 +437,7 @@ qla2x00_sysfs_write_optrom_ctl(struct file *filp, struct kobject *kobj,
 		}
 
 		ha->optrom_region_start = start;
-		ha->optrom_region_size = start + size;
+		ha->optrom_region_size = size;
 
 		ha->optrom_state = QLA_SWRITING;
 		ha->optrom_buffer = vmalloc(ha->optrom_region_size);