vtd: During parsing DMAR table, if find RMRR is incorrect, return error.

Signed-off-by: Weidong Han <weidong.han@intel.com>

xen/drivers/passthrough/vtd/dmar.c

@@ -349,6 +349,12 @@ acpi_parse_one_rmrr(struct acpi_dmar_entry_header *header)
     void *dev_scope_start, *dev_scope_end;
     int ret = 0;
 
+    if ( rmrr->base_address >= rmrr->end_address )
+    {
+        dprintk(XENLOG_ERR VTDPREFIX, "RMRR is incorrect.\n");
+        return -EFAULT;
+    }
+
     rmrru = xmalloc(struct acpi_rmrr_unit);
     if ( !rmrru )
         return -ENOMEM;