[kerx] Use subtable range for runtime checks
diff --git a/src/hb-aat-layout-kerx-table.hh b/src/hb-aat-layout-kerx-table.hh
index dd6e817..c7cb367 100644
--- a/src/hb-aat-layout-kerx-table.hh
+++ b/src/hb-aat-layout-kerx-table.hh
@@ -124,7 +124,7 @@
     TRACE_APPLY (this);
 
     accelerator_t accel (*this,
-			 c->sanitizer.end, /* XXX Use SubTable length? */
+			 c->sanitizer.end,
 			 c->face->get_num_glyphs ());
     hb_kern_machine_t<accelerator_t> machine (accel);
     machine.kern (c->font, c->buffer, c->plan->kern_mask);
@@ -328,6 +328,8 @@
       if (reverse)
         c->buffer->reverse ();
 
+      c->sanitizer.set_object (*table);
+
       /* XXX Reverse-kern is not working yet...
        * hb_kern_machine_t would need to know that it's reverse-kerning.
        * Or better yet, make it work in reverse as well, so we don't have