diff -rdu lua-5.1.3.orig/src/lundump.c lua-5.1.3/src/lundump.c
--- lua-5.1.3.orig/src/lundump.c        2008-02-12 16:17:59.000000000 +0000
+++ lua-5.1.3/src/lundump.c     2008-02-12 16:26:32.000000000 +0000
@@ -161,7 +160,9 @@
 
 static Proto* LoadFunction(LoadState* S, TString* p)
 {
- Proto* f=luaF_newproto(S->L);
+ Proto* f;
+ if (++S->L->nCcalls > LUAI_MAXCCALLS) error(S,"code too deep");
+ f=luaF_newproto(S->L);
  setptvalue2s(S->L,S->L->top,f); incr_top(S->L);
  f->source=LoadString(S); if (f->source==NULL) f->source=p;
  f->linedefined=LoadInt(S);
@@ -175,6 +176,7 @@
  LoadDebug(S,f);
  IF (!luaG_checkcode(f), "bad code");
  S->L->top--;
+ S->L->nCcalls--;
  return f;
 }