[subset] Limit the iterations of the closure algorithm.
Prevents O(n^2) run times.
diff --git a/src/hb-ot-layout.cc b/src/hb-ot-layout.cc
index 0eba88a..01ca514 100644
--- a/src/hb-ot-layout.cc
+++ b/src/hb-ot-layout.cc
@@ -971,6 +971,7 @@
OT::hb_closure_context_t c (face, glyphs, &done_lookups);
const OT::GSUB& gsub = _get_gsub (face);
+ unsigned int iteration_count = 0;
unsigned int glyphs_length;
do
{
@@ -985,7 +986,9 @@
for (unsigned int i = 0; i < gsub.get_lookup_count (); i++)
gsub.get_lookup (i).closure (&c, i);
}
- } while (glyphs_length != glyphs->get_population ());
+ iteration_count++;
+ } while (iteration_count <= HB_CLOSURE_MAX_STAGES
+ && glyphs_length != glyphs->get_population ());
}
/*
