From ebaa961812e7b29eee554025a6253d676cea6ce0 Mon Sep 17 00:00:00 2001
From: Josh Stone <jistone@redhat.com>
Date: Fri, 16 Oct 2009 18:32:12 -0700
Subject: Ensure that DWARF keeps loc2c to a reasonable stack depth

* dwflpp.cxx (dwflpp::express_as_string): Limit stack depth to 32.
---
 dwflpp.cxx | 7 +++++++
 1 file changed, 7 insertions(+)

(limited to 'dwflpp.cxx')

diff --git a/dwflpp.cxx b/dwflpp.cxx
index b1d9a32b..0c45eb7d 100644
--- a/dwflpp.cxx
+++ b/dwflpp.cxx
@@ -2182,8 +2182,15 @@ dwflpp::express_as_string (string prelude,
 
   fprintf(memstream, "{\n");
   fprintf(memstream, "%s", prelude.c_str());
+
   unsigned int stack_depth;
   bool deref = c_emit_location (memstream, head, 1, &stack_depth);
+
+  // Ensure that DWARF keeps loc2c to a "reasonable" stack size
+  // 32 intptr_t leads to max 256 bytes on the stack
+  if (stack_depth > 32)
+    throw semantic_error("oversized DWARF stack");
+
   fprintf(memstream, "%s", postlude.c_str());
   fprintf(memstream, "  goto out;\n");
 
-- 
cgit